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Sample records for azoic diazo component

  1. Five-membered rings as diazo components in optical data storage devices: An ab initio investigation of the lowest singlet excitation energies

    DEFF Research Database (Denmark)

    Åstrand, P.-O.; Sommer-Larsen, P.; Hvilsted, Søren

    2000-01-01

    been investigated as diazo components for a potential use in optical das storage materials. It is found that the diazo compounds with two heterocyclic five-membered rings have pi --> pi* excitation energies corresponding to laser wavelengths in the region 450-500 nm whereas one five-membered ring...... and a phenyl group as diazo components results in wavelengths in the region 400-335 nm. (C) 2000 Published by Elsevier Science B.V....

  2. Enantioselective Synthesis of α-Mercapto-β-amino Esters via Rh(II)/Chiral Phosphoric Acid-Cocatalyzed Three-Component Reaction of Diazo Compounds, Thiols, and Imines.

    Science.gov (United States)

    Xiao, Guolan; Ma, Chaoqun; Xing, Dong; Hu, Wenhao

    2016-12-02

    An enantioselective method for the synthesis of α-mercapto-β-amino esters has been developed via a rhodium(II)/chiral phosphoric acid-cocatalyzed three-component reaction of diazo compounds, thiols, and imines. This transformation is proposed to proceed through enantioselective trapping of the sulfonium ylide intermediate generated in situ from the diazo compound and thiol by the phosphoric acid-activated imine. With this method, a series of α-mercapto-β-amino esters were obtained in good yields with moderate to good stereoselectivities.

  3. Diazo groups endure metabolism and enable chemoselectivity in cellulo.

    Science.gov (United States)

    Andersen, Kristen A; Aronoff, Matthew R; McGrath, Nicholas A; Raines, Ronald T

    2015-02-25

    We introduce a stabilized diazo group as a reporter for chemical biology. ManDiaz, which is a diazo derivative of N-acetylmannosamine, is found to endure cellular metabolism and label the surface of a mammalian cell. There its diazo group can undergo a 1,3-dipolar cycloaddition with a strained alkyne, providing a signal comparable to that from the azido congener, ManNAz. The chemoselectivity of diazo and alkynyl groups enables dual labeling of cells that is not possible with azido and alkynyl groups. Thus, the diazo group, which is approximately half the size of an azido group, provides unique opportunities for orthogonal labeling of cellular components.

  4. Pyridine group assisted addition of diazo-compounds to imines in the 3-CC reaction of 2-aminopyridines, aldehydes, and diazo-compounds.

    Science.gov (United States)

    Gulevich, Anton V; Helan, Victoria; Wink, Donald J; Gevorgyan, Vladimir

    2013-02-15

    A novel three-component coupling (3-CC) reaction of 2-aminoazines, aromatic aldehydes, and diazo-compounds producing polyfunctional β-amino-α-diazo-compounds has been developed. The reaction features an unprecedented heterocycle-assisted addition of a diazo-compound to an imine. The obtained diazoesters were efficiently converted into valuable heterocycles as well as β-amino acid derivatives.

  5. Deserts on the sea floor: Edward Forbes and his azoic hypothesis for a lifeless deep ocean.

    Science.gov (United States)

    Anderson, Thomas R; Rice, Tony

    2006-12-01

    While dredging in the Aegean Sea during the mid-19th century, Manxman Edward Forbes noticed that plants and animals became progressively more impoverished the greater the depth they were from the surface of the water. By extrapolation Forbes proposed his now infamous azoic hypothesis, namely that life would be extinguished altogether in the murky depths of the deep ocean. The whole idea seemed so entirely logical given the enormous pressure, cold and eternal darkness of this apparently uninhabitable environment. Yet we now know that the sea floor is teeming with life. Curiously, it took 25 years for the azoic hypothesis to fall from grace. This was despite the presence of ample contrary evidence, including starfishes, worms and other organisms that seemingly originated from the deep seabed. This is a tale of scientists ignoring observations that ran counter to their deep-seated, yet entirely erroneous, beliefs.

  6. Pyridine Group-Assisted Addition of Diazo-Compounds to Imines in the 3-CC Reaction of 2-Aminopyridines, Aldehydes, and Diazo-Compounds

    Science.gov (United States)

    Gulevich, Anton V.; Helan, Victoria; Wink, Donald J.

    2013-01-01

    A novel three-component (3-CC) coupling reaction of 2-aminoazines, aromatic aldehydes and diazo-compounds producing polyfunctional β-amino-α-diazo-compounds has been developed. The reaction features an unprecedented heterocycle-assisted addition of a diazo-compound to an imine. The obtained diazoesters were efficiently converted into valuable heterocycles, as well as to β-amino acid derivatives. PMID:23373731

  7. Diazo Compounds: Versatile Tools for Chemical Biology.

    Science.gov (United States)

    Mix, Kalie A; Aronoff, Matthew R; Raines, Ronald T

    2016-12-16

    Diazo groups have broad and tunable reactivity. That and other attributes endow diazo compounds with the potential to be valuable reagents for chemical biologists. The presence of diazo groups in natural products underscores their metabolic stability and anticipates their utility in a biological context. The chemoselectivity of diazo groups, even in the presence of azido groups, presents many opportunities. Already, diazo compounds have served as chemical probes and elicited novel modifications of proteins and nucleic acids. Here, we review advances that have facilitated the chemical synthesis of diazo compounds, and we highlight applications of diazo compounds in the detection and modification of biomolecules.

  8. Diazo Compounds: Versatile Tools for Chemical Biology

    OpenAIRE

    Mix, Kalie A.; Aronoff, Matthew R.; Raines, Ronald T.

    2016-01-01

    Diazo groups have broad and tunable reactivity. That and other attributes endow diazo compounds with the potential to be valuable reagents for chemical biologists. The presence of diazo groups in natural products underscores their metabolic stability and anticipates their utility in a biological context. The chemoselectivity of diazo groups, even in the presence of azido groups, presents many opportunities. Already, diazo compounds have served as chemical probes and elicited novel modificatio...

  9. Diazo compounds in the chemistry of fullerenes

    International Nuclear Information System (INIS)

    Tuktarov, Airat R; Dzhemilev, Usein M

    2010-01-01

    Experimental and theoretical data on the reactions of different diazo compounds (diazomethane, its derivatives, cyclic diazo compounds and diazocarbonyl compounds) with fullerenes are summarized. The structures and stereochemistry of cycloadducts formed in these reactions are considered.

  10. Diazo compounds in the chemistry of fullerenes

    Science.gov (United States)

    Tuktarov, Airat R.; Dzhemilev, Usein M.

    2010-09-01

    Experimental and theoretical data on the reactions of different diazo compounds (diazomethane, its derivatives, cyclic diazo compounds and diazocarbonyl compounds) with fullerenes are summarized. The structures and stereochemistry of cycloadducts formed in these reactions are considered.

  11. Diazo compounds in the chemistry of fullerenes

    Energy Technology Data Exchange (ETDEWEB)

    Tuktarov, Airat R; Dzhemilev, Usein M [Institute of Petrochemistry and Catalysis, Russian Academy of Sciences, Ufa (Russian Federation)

    2010-09-14

    Experimental and theoretical data on the reactions of different diazo compounds (diazomethane, its derivatives, cyclic diazo compounds and diazocarbonyl compounds) with fullerenes are summarized. The structures and stereochemistry of cycloadducts formed in these reactions are considered.

  12. Synthesis and reactions of diazocarbonyl compounds. I. Reaction of 1-diazo-3-, 1-diazo-4-, and 1-diazo-5-phthalimidoalkan-2-ones with hydrazine hydrate. Synthesis of 1-diazo-3-, 1-diazo-4, and 1-diazo-5-arenesulfamoyl-alkan-2-ones

    International Nuclear Information System (INIS)

    Sipyagin, A.M.; Kartsev, V.G.

    1986-01-01

    The reaction of hydrazine hydrate with 1-diazo-3-, 1-diazo-4-, and 1-diazo-5-phthalimidoalkan-2-ones containing a substituent at the α position to the phthalimide group in the hydrocarbon chain leads to the formation of 1-diazo-3- and 1-diazo-4-(2-hydrazidophenylcarbamoyl)alkan-2-ones. On heating in the presence of an excess of hydrazine hydrate the reaction products are 1-diazo-3-, 1-diazo-4-, and 1-diazo-5-aminoalkan-2-ones. Various 1-diazo-3-, 1-diazo-4-, and 1-diazo-5-arenesulfamoyl-alkan-2-ones were synthesized in the reaction of arenesulfonyl chlorides with 1-diazo-3-, 1-diazo-4-, and 1-diazo-5-aminoalkan-2-ones in the presence of triethylamine

  13. Homologation Reaction of Ketones with Diazo Compounds.

    Science.gov (United States)

    Candeias, Nuno R; Paterna, Roberta; Gois, Pedro M P

    2016-03-09

    This review covers the addition of diazo compounds to ketones to afford homologated ketones, either in the presence or in the absence of promoters or catalysts. Reactions with diazoalkanes, aryldiazomethanes, trimethylsilyldiazomethane, α-diazo esters, and disubstituted diazo compounds are covered, commenting on the complex regiochemistry of the reaction and the nature of the catalysts and promoters. The recent reports on the enantioselective version of ketone homologation reactions are gathered in one section, followed by reports on the use of cyclic ketones ring expansion in total synthesis. Although the first reports of this reaction appeared in the literature almost one century ago, the recent achievements, in particular, for the asymmetric version, forecast the development of new breakthroughs in the synthetically valuable field of diazo chemistry.

  14. Optimized Diazo Scaffold for Protein Esterification

    Science.gov (United States)

    Mix, Kalie A.

    2015-01-01

    The O-alkylation of carboxylic acids with diazo compounds provides a means to esterify carboxylic acids in aqueous solution. A Hammett analysis of the reactivity of diazo compounds derived from phenylglycinamide revealed that the p-methylphenylglycinamide scaffold has an especially high reaction rate and ester:alcohol product ratio, and esterifies protein carboxyl groups more efficiently than does any known reagent. PMID:25938936

  15. 40 CFR 721.4596 - Diazo substituted carbomonocyclic metal complex.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Diazo substituted carbomonocyclic... Specific Chemical Substances § 721.4596 Diazo substituted carbomonocyclic metal complex. (a) Chemical... as a diazo substituted carbomonocyclic metal complex (PMN P-94-1039) is subject to reporting under...

  16. Discovery of a diazo-forming enzyme in cremeomycin biosynthesis.

    Science.gov (United States)

    Waldman, Abraham J; Balskus, Emily P

    2018-05-17

    The molecular architectures and potent bioactivities of diazo-containing natural products have attracted the interest of synthetic and biological chemists. Despite this attention, the biosynthetic enzymes involved in diazo group construction have not been identified. Here, we show the ATP-dependent enzyme CreM installs the diazo group in cremeomycin via late-stage N-N bond formation using nitrite. This finding should inspire efforts to use diazo-forming enzymes in biocatalysis and synthetic biology and enable genome-based discovery of new diazo-containing metabolites.

  17. Diazo compounds in continuous-flow technology.

    Science.gov (United States)

    Müller, Simon T R; Wirth, Thomas

    2015-01-01

    Diazo compounds are very versatile reagents in organic chemistry and meet the challenge of selective assembly of structurally complex molecules. Their leaving group is dinitrogen; therefore, they are very clean and atom-efficient reagents. However, diazo compounds are potentially explosive and extremely difficult to handle on an industrial scale. In this review, it is discussed how continuous flow technology can help to make these powerful reagents accessible on large scale. Microstructured devices can improve heat transfer greatly and help with the handling of dangerous reagents safely. The in situ formation and subsequent consumption of diazo compounds are discussed along with advances in handling diazomethane and ethyl diazoacetate. The potential large-scale applications of a given methodology is emphasized. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Diazo techniques for remote sensor data analysis

    Science.gov (United States)

    Mount, S.; Whitebay, L. E.

    1979-01-01

    Cost and time to extract land use maps, natural-resource surveys, and other data from aerial and satellite photographs are reduced by diazo processing. Process can be controlled to enhance features such as vegetation, land boundaries, and bodies of water.

  19. Synthesis of Substituted 1,4-Dioxenes through O-H Insertion and Cyclization Using Keto-Diazo Compounds.

    Science.gov (United States)

    Davis, Owen A; Croft, Rosemary A; Bull, James A

    2016-11-18

    1,4-Dioxenes present interesting potential as synthetic intermediates and as unusual motifs for incorporation into biologically active compounds. Here, an efficient synthesis of functionalized 1,4-dioxenes is achieved in two steps. Using keto-diazo compounds, a ruthenium catalyzed O-H insertion with β-halohydrins followed by treatment with base results in cyclization with excellent selectivity, through O-alkylation of the keto-enolate. A variety of halohydrins and anion-stabilizing groups in the diazo-component are tolerated, affording novel functionalized dioxenes. Enantioenriched β-bromohydrins provide enantioenriched 1,4-dioxenes.

  20. Diazo Printing of ERTS Color Composites

    Science.gov (United States)

    Mcmurtry, G. J.; Petersen, G. W. (Principal Investigator); Kowalik, W. S.

    1975-01-01

    The author has identified the following significant results. ERTS-1 color composites were made with the help of a Diazo developer and printer. Five single channel, density standards were established, using typical ERTS images, in order to determine exposure time. These standards were used to develop a graph from which the exposure time for any transparency can be estimated. Exposure times varied from 3 to 30 minutes, and clear colored polyester sheets from two manufactures were used with slightly different, but equally successful, results.

  1. Iodine-catalyzed diazo activation to access radical reactivity.

    Science.gov (United States)

    Li, Pan; Zhao, Jingjing; Shi, Lijun; Wang, Jin; Shi, Xiaodong; Li, Fuwei

    2018-05-17

    Transition-metal-catalyzed diazo activation is a classical way to generate metal carbene, which are valuable intermediates in synthetic organic chemistry. An alternative iodine-catalyzed diazo activation is disclosed herein under either photo-initiated or thermal-initiated conditions, which represents an approach to enable carbene radical reactivity. This metal-free diazo activation strategy were successfully applied into olefin cyclopropanation and epoxidation, and applying this method to pyrrole synthesis under thermal-initiated conditions further demonstrates the unique reactivity using this method over typical metal-catalyzed conditions.

  2. The Generation of Diazo Compounds in Continuous-Flow.

    Science.gov (United States)

    Hock, Katharina J; Koenigs, Rene M

    2018-03-25

    Toxic, cancerogenic and explosive - these attributes are typically associated with diazo compounds. Nonetheless, diazo compounds are nowadays a highly demanded class of reagents for organic synthesis, yet the concerns with regards to safe and scalable transformations of these compounds are still exceptionally high. Lately, the research area of the continuous-flow synthesis of diazo compounds attracted significant interest and a whole variety of protocols for their "on-demand" preparation have been realized to date. This concept article focuses on the recent developments using continuous-flow technologies to access diazo compounds; thus minimizing risks and hazards when working with this particular class of compounds. In this article we discuss these concepts and highlight different pre-requisites to access and to perform downstream functionalization reaction. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Influence of interfiled silver-gelatin and diazo microfiches

    International Nuclear Information System (INIS)

    Habara, Tadashi; Koike, Kunio; Furuya, Minoru; Matsuda, Kiminori; Kajiro, Tadashi; Yamamoto, Emiko; Sato, Kenji

    1981-01-01

    In case of filing silver based microfiche stored with diazo based one, image on the silver is likely to deteriorate by residual ammonia on the diazo. Experiments were made to examine the truth or falsehood of this phenomena under various conditions of humidity, filing time and quantity of residual ammonia. In addition to the experiments, investigations were made on the silver interfiled in practice for eight years. These results are also reported. (author)

  4. Fluorogenic Strain-Promoted Alkyne-Diazo Cycloadditions.

    Science.gov (United States)

    Friscourt, Frédéric; Fahrni, Christoph J; Boons, Geert-Jan

    2015-09-28

    Fluorogenic reactions, in which non- or weakly fluorescent reagents produce highly fluorescent products, are attractive for detecting a broad range of compounds in the fields of bioconjugation and material sciences. Herein, we report that a dibenzocyclooctyne derivative modified with a cyclopropenone moiety (Fl-DIBO) can undergo fast strain-promoted cycloaddition reactions under catalyst-free conditions with azides, nitrones, nitrile oxides, as well as mono- and disubstituted diazo-derivatives. Although the reaction with nitrile oxides, nitrones, and disubstituted diazo compounds gave cycloadducts with low quantum yield, monosubstituted diazo reagents produced 1H-pyrazole derivatives that exhibited an approximately 160-fold fluorescence enhancement over Fl-DIBO combined with a greater than 10,000-fold increase in brightness. Concluding from quantum chemical calculations, fluorescence quenching of 3H-pyrazoles, which are formed by reaction with disubstituted diazo-derivatives, is likely due to the presence of energetically low-lying (n,π*) states. The fluorogenic probe Fl-DIBO was successfully employed for the labeling of diazo-tagged proteins without detectable background signal. Diazo-derivatives are emerging as attractive reporters for the labeling of biomolecules, and the studies presented herein demonstrate that Fl-DIBO can be employed for visualizing such biomolecules without the need for probe washout. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Metal-Diazo Radicals of α-Carbonyl Diazomethanes

    Science.gov (United States)

    Li, Feifei; Xiao, Longqiang; Liu, Lijian

    2016-03-01

    Metal-diazo radicals of α-carbonyl diazomethanes are new members of the radical family and are precursors to metal-carbene radicals. Herein, using electron paramagnetic resonance spectroscopy with spin-trapping, we detect diazo radicals of α-carbonyl diazomethanes, induced by [RhICl(cod)]2, [CoII(por)] and PdCl2, at room temperature. The unique quintet signal of the Rh-diazo radical was observed in measurements of α-carbonyl diazomethane adducts of [RhICl(cod)]2 in the presence of 5,5-dimethyl-pyrroline-1-N-oxide (DMPO). DFT calculations indicated that 97.2% of spin density is localized on the diazo moiety. Co- and Pd-diazo radicals are EPR silent but were captured by DMPO to form spin adducts of DMPO-N• (triplet-of-sextets signal). The spin-trapping also provides a powerful tool for detection of metal-carbene radicals, as evidenced by the DMPO-trapped carbene radicals (DMPO-C•, sextet signal) and 2-methyl-2-nitrosopropane-carbene adducts (MNP-C•, doublet-of-triplets signal). The transformation of α-carbonyl diazomethanes to metal-carbene radicals was confirmed to be a two-step process via metal-diazo radicals.

  6. Rhodium Catalyzed Intramolecular C-H Insertion of α-Aryl-α-diazo Ketones

    Science.gov (United States)

    Taber, Douglass F.; Tian, Weiwei

    2011-01-01

    Direct diazo transfer proceeds smoothly with α-aryl ketones. The derived α-aryl-α-diazo ketones cyclize efficiently with Rh catalysis to give the corresponding α-aryl cyclopentanones. PMID:17385917

  7. Rh(II)-catalyzed reactions of differentially substituted bis(diazo) functionalities.

    Science.gov (United States)

    Bonderoff, Sara A; Padwa, Albert

    2013-08-16

    The chemoselective reaction of donor/acceptor (D/A) and acceptor/acceptor (A/A) diazo moieties in the same molecule was examined using 3-diazo-1-(ethyl 2-diazomalonyl)indolin-2-one under rhodium(II) catalysis. The D/A diazo group undergoes selective cyclopropanation as well as XH-insertion, leaving behind the second diazo group for a further intramolecular dipolar cycloaddition reaction.

  8. A nitrous acid biosynthetic pathway for diazo group formation in bacteria.

    Science.gov (United States)

    Sugai, Yoshinori; Katsuyama, Yohei; Ohnishi, Yasuo

    2016-02-01

    Although some diazo compounds have bioactivities of medicinal interest, little is known about diazo group formation in nature. Here we describe an unprecedented nitrous acid biosynthetic pathway responsible for the formation of a diazo group in the biosynthesis of the ortho-diazoquinone secondary metabolite cremeomycin in Streptomyces cremeus. This finding provides important insights into the biosynthetic pathways not only for diazo compounds but also for other naturally occurring compounds containing nitrogen-nitrogen bonds.

  9. Direct C-H alkylation and indole formation of anilines with diazo compounds under rhodium catalysis.

    Science.gov (United States)

    Mishra, Neeraj Kumar; Choi, Miji; Jo, Hyeim; Oh, Yongguk; Sharma, Satyasheel; Han, Sang Hoon; Jeong, Taejoo; Han, Sangil; Lee, Seok-Yong; Kim, In Su

    2015-12-18

    The rhodium(III)-catalyzed direct functionalization of aniline C-H bonds with α-diazo compounds is described. These transformations provide a facile construction of ortho-alkylated anilines with diazo malonates or highly substituted indoles with diazo acetoacetates.

  10. Enantioselective Copper-Catalyzed Oxy-Alkynylation of Diazo Compounds.

    Science.gov (United States)

    Hari, Durga Prasad; Waser, Jerome

    2017-06-28

    Enantioselective catalytic methods allowing the addition of both a nucleophile and an electrophile onto diazo compounds give a fast access into important building blocks. Herein, we report the highly enantioselective oxyalkynylation of diazo compounds using ethynylbenziodoxol-(on)e reagents and a simple copper bisoxazoline catalyst. The obtained α-benzoyloxy propargylic esters are useful building blocks, which are difficult to synthesize in enantiopure form using other methods. The obtained products could be efficiently transformed into vicinal diols and α-hydroxy propargylic esters without loss in enantiopurity.

  11. Conversion of Azides into Diazo Compounds in Water

    Science.gov (United States)

    Chou, Ho-Hsuan; Raines, Ronald T.

    2013-01-01

    Diazo compounds are in widespread use in synthetic organic chemistry, but have untapped potential in chemical biology. We report on the design and optimization of a phosphinoester that mediates the efficient conversion of azides into diazo compounds in phosphate buffer at neutral pH and room temperature. High yields are maintained in the presence of common nucleophilic or electrophilic functional groups, and reaction progress can be monitored by colorimetry. As azido groups are easy to install and maintain in biopolymers or their ligands, this new mode of azide reactivity could have substantial utility in chemical biology. PMID:24053717

  12. Practical Microform Materials for Libraries: Silver, Diazo, Vesicular.

    Science.gov (United States)

    Veaner, Allen B.

    1982-01-01

    Remarks on the relative permanence and durability of three types of film in use in library microform reproduction (silver, diazo, and vesicular) and points out some technical and economic facts that govern the choice of microform materials for libraries. A 6-item reference list is included. (Author/JL)

  13. 115 THE SENSITIVITY OF DIAZO TEST IN THE DIAGNOSIS OF ...

    African Journals Online (AJOL)

    Salmonella typhi was the predominant serotype causing typhoid/paratyphoid fevers, followed by S. paratypi A; S. paratyphi C and S. paratyphi B respectively. Although. Diazo test does not appear to be reliable, it could still be useful alongside with Widal agglutination test in endemic rural or urban areas where electricity and ...

  14. α-Diazo oxime ethers for N-heterocycle synthesis.

    Science.gov (United States)

    Choi, Subin; Ha, Sujin; Park, Cheol-Min

    2017-06-01

    This Feature Article introduces the preparation and synthetic utility of α-diazo oxime ethers. α-Oximino carbenes are useful synthons for N-heterocycles, and can be easily prepared from α-diazo oxime ethers as precursors. We begin with the preparation of α-diazo oxime ethers and their application in [3+2] cycloaddition. It turns out that the nature of metals bound to carbenes plays a crucial role in modulating the reactivity of α-oximino carbenes, in which copper carbenes smoothly react with enamines, whereas the less reactive enol ethers and nitriles require gold carbenes. In Section 3.2, a discussion on N-O and C-H bond activation is presented. Carbenes derived from diazo oxime ethers show unique reactivity towards N-O and C-H bond activation, in which the proximity of the two functionalities, carbene and oxime ether, dictates the preferred reaction pathways toward pyridines, pyrroles, and 2H-azirines. In Section 3.3, the development of tandem reactions based on α-diazo oxime ethers is discussed. The nature of carbenes in which whether free carbenes or metal complexes are involved dissects the pathway and forms different types of 2H-azirines. The 2H-azirine formation turned out to be an excellent platform for the tandem synthesis of N-heterocycles including pyrroles and pyridines. In the last section, we describe the electrophilic activation of 2H-azirines with vinyl carbenes and oximino carbenes. The resulting azirinium species undergo rapid ring expansion rearrangements to form pyridines and pyrazines.

  15. The Cremeomycin Biosynthetic Gene Cluster Encodes a Pathway for Diazo Formation.

    Science.gov (United States)

    Waldman, Abraham J; Pechersky, Yakov; Wang, Peng; Wang, Jennifer X; Balskus, Emily P

    2015-10-12

    Diazo groups are found in a range of natural products that possess potent biological activities. Despite longstanding interest in these metabolites, diazo group biosynthesis is not well understood, in part because of difficulties in identifying specific genes linked to diazo formation. Here we describe the discovery of the gene cluster that produces the o-diazoquinone natural product cremeomycin and its heterologous expression in Streptomyces lividans. We used stable isotope feeding experiments and in vitro characterization of biosynthetic enzymes to decipher the order of events in this pathway and establish that diazo construction involves late-stage N-N bond formation. This work represents the first successful production of a diazo-containing metabolite in a heterologous host, experimentally linking a set of genes with diazo formation. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Functionalizing the γ-Position of α-Diazo-β-ketoesters.

    Science.gov (United States)

    Nguyen, Thu Q; Alqurafi, Maha; Edwards, Cash; Nguyen, Pauline; Kim, Jean; Casco, Samuel; Bennet, Maricka; Chiang, Christopher; Lohry, Maureen; Cox, Melina; Meshram, Byron; Le, Duyen; Kim, Eugene; Smriti, Snigdha; Oelschlaeger, Peter; Buynak, John D

    2016-06-27

    Although α-diazo-β-ketoesters are synthetically versatile intermediates, methodology for introducing this functionality into complex molecules is still limited, most frequently involving a carboxylic acid precursor, which is then activated and transformed into a β-ketoester, with the diazo group being subsequently added with a diazo transfer reagent. While introducing this highly functional moiety in a convergent one step process would be ideal, such an objective is limited by the relatively few studies which address functionalization of the α-diazo-β-ketoester at the γ-position. In the present investigation, we evaluate strategies, both new and established, for functionalizing α-diazo-β-ketoesters, particularly with regard to generating compounds prospectively useful in the synthesis of C1-substituted carbapenems. We report the first δ-aldehydo-α-diazo-β-ketoester as well as a method for its oxidation to the corresponding methyl ester, and the formation of a new substituted pyrazole under basic conditions.

  17. A mild, efficient method for the oxidation of α-diazo-β-hydroxyesters to α-diazo-β-ketoesters

    OpenAIRE

    Li, Puhui; Majireck, Max M.; Korboukh, Ilia; Weinreb, Steven M.

    2008-01-01

    A wide variety of α-diazo-β-ketoesters can be prepared in good overall yields via a two-step sequence involving addition of ethyl lithiodiazoacetate to aliphatic, aromatic and conjugated aldehydes followed by mild oxidation with the Dess-Martin periodinane.

  18. A mild, efficient method for the oxidation of α-diazo-β-hydroxyesters to α-diazo-β-ketoesters

    Science.gov (United States)

    Li, Puhui; Majireck, Max M.; Korboukh, Ilia; Weinreb, Steven M.

    2008-01-01

    A wide variety of α-diazo-β-ketoesters can be prepared in good overall yields via a two-step sequence involving addition of ethyl lithiodiazoacetate to aliphatic, aromatic and conjugated aldehydes followed by mild oxidation with the Dess-Martin periodinane. PMID:19421308

  19. Synthesis of Cyclic α-Diazo-β-keto Sulfoxides in Batch and Continuous Flow.

    Science.gov (United States)

    McCaw, Patrick G; Buckley, Naomi M; Eccles, Kevin S; Lawrence, Simon E; Maguire, Anita R; Collins, Stuart G

    2017-04-07

    Diazo transfer to β-keto sulfoxides to form stable isolable α-diazo-β-keto sulfoxides has been achieved for the first time. Both monocyclic and benzofused ketone derived β-keto sulfoxides were successfully explored as substrates for diazo transfer. Use of continuous flow leads to isolation of the desired compounds in enhanced yields relative to standard batch conditions, with short reaction times, increased safety profile, and potential to scale up.

  20. α-Diazo-β-ketonitriles: uniquely reactive substrates for arene and alkene cyclopropanation.

    Science.gov (United States)

    Nani, Roger R; Reisman, Sarah E

    2013-05-15

    An investigation of the intramolecular cyclopropanation reactions of α-diazo-β-ketonitriles is reported. These studies reveal that α-diazo-β-ketonitriles exhibit unique reactivity in their ability to undergo arene cyclopropanation reactions; other similar acceptor-acceptor-substituted diazo substrates instead produce mixtures of C-H insertion and dimerization products. α-Diazo-β-ketonitriles also undergo highly efficient intramolecular cyclopropanation of tri- and tetrasubstituted alkenes. In addition, the α-cyano-α-ketocyclopropane products are demonstrated to serve as substrates for SN2, SN2', and aldehyde cycloaddition reactions.

  1. Stereoselective Synthesis of Highly Functionalized α-Diazo-β-ketoalkanoates via Catalytic Onepot Mukaiyama-Aldol Reactions

    Science.gov (United States)

    Zhou, Lei; Doyle, Michael P.

    2010-01-01

    Methyl diazoacetoacetate undergoes zinc triflate catalyzed condensation with a broad selection of aldehydes to produce δ-siloxy-α-diazo-β-ketoalkanoates in good yield, and δ-hydroxy-α-diazo-β-ketoalkanoates are formed with high diastereoselectivity in reactions with α-diazo-β-ketopentanoate promoted by dibutylboron triflate. PMID:20102172

  2. Enantioselective copper catalysed intramolecular C-H insertion reactions of α-diazo-β-keto sulfones, α-diazo-β-keto phosphine oxides and 2-diazo-1,3-diketones; the influence of the carbene substituent.

    Science.gov (United States)

    Shiely, Amy E; Slattery, Catherine N; Ford, Alan; Eccles, Kevin S; Lawrence, Simon E; Maguire, Anita R

    2017-03-22

    Enantioselectivities in C-H insertion reactions, employing the copper-bis(oxazoline)-NaBARF catalyst system, leading to cyclopentanones are highest with sulfonyl substituents on the carbene carbon, and furthermore, the impact is enhanced by increased steric demand on the sulfonyl substituent (up to 91%ee). Enantioselective intramolecular C-H insertion reactions of α-diazo-β-keto phosphine oxides and 2-diazo-1,3-diketones are reported for the first time.

  3. Taming hazardous chemistry in flow: The continuous processing of diazo and diazonium compounds

    OpenAIRE

    Deadman, Benjamin J.; Collins, Stuart G.; Maguire, Anita R.

    2014-01-01

    The synthetic utilities of the diazo and diazonium groups are matched only by their reputation for explosive decomposition. Continuous processing technology offers new opportunities to make and use these versatile intermediates at a range of scales with improved safety over traditional batch processes. In this minireview, the state of the art in the continuous flow processing of reactive diazo and diazonium species is discussed.

  4. Mass spectrometric investigation of cyclication of diazo compounds. XI. Cyclization of 1-diazo-4-methoxycarbonyl-2-butanones

    International Nuclear Information System (INIS)

    Lebedev, A.T.; Kazaryan, A.G.; Sharbatyan, P.A.; Sipyagin, A.M.; Kartsev, V.G.; Petrosyan, V.S.

    1988-01-01

    On the basis of the electron-impact mass spectra of a series of 1-diazo-4-methoxycarbonyl-2-butanones, the data from high-solution mass spectrometry, and the spectrum of the deuterated analog it was shown that the [M-N 2 ] +center-dot ions formed at the first stage in the fragmentation of the molecular ions of these compounds are partly stabilized with the formation of pseudomolecular ions of oxolanones. The molecular ions of the diazo ketones themselves can dissociate in various directions. The many-path dissociation makes it possible to suppose that the yield of oxolanones formed during cyclization in solution under the influence of acidic agents is small

  5. Taming tosyl azide: the development of a scalable continuous diazo transfer process.

    Science.gov (United States)

    Deadman, Benjamin J; O'Mahony, Rosella M; Lynch, Denis; Crowley, Daniel C; Collins, Stuart G; Maguire, Anita R

    2016-04-07

    Heat and shock sensitive tosyl azide was generated and used on demand in a telescoped diazo transfer process. Small quantities of tosyl azide were accessed in a 'one pot' batch procedure using shelf stable, readily available reagents. For large scale diazo transfer reactions tosyl azide was generated and used in a telescoped flow process, to mitigate the risks associated with handling potentially explosive reagents on scale. The in situ formed tosyl azide was used to rapidly perform diazo transfer to a range of acceptors, including β-ketoesters, β-ketoamides, malonate esters and β-ketosulfones. An effective in-line quench of sulfonyl azides was also developed, whereby a sacrificial acceptor molecule ensured complete consumption of any residual hazardous diazo transfer reagent. The telescoped diazo transfer process with in-line quenching was used to safely prepare over 21 g of an α-diazocarbonyl in >98% purity without any column chromatography.

  6. Bent CNN bond of diazo compounds, RR'(Cdbnd N+dbnd N-)

    Science.gov (United States)

    Akita, Motoko; Takahashi, Mai; Kobayashi, Keiji; Hayashi, Naoto; Tukada, Hideyuki

    2013-02-01

    The reaction of ninhydrin with benzophenone hydrazone afforded 2-diazo-3-diphenylmethylenehydrazono-1-indanone 1 and 2-diazo-1,3-bis(diphenylmethylenehydrazono)indan 2. X-ray crystal structure analyses of these products showed that the diazo functional group Cdbnd N+dbnd N- of 1 is bent by 172.9°, while that of 2 has a linear geometry. The crystal structure data of diazo compounds have been retrieved from the Cambridge Structural Database (CSD), which hit 177 entries to indicate that the angle of 172.9° in 1 lies in one of the most bent structures. The CSD search also indicated that diazo compounds consisting of a distorted diazo carbon tend to bend the Cdbnd N+dbnd N- bond. On the basis of DFT calculations (B3LYP/6-311++G(d,p)) of model compounds, it was revealed that the bending of the CNN bond is principally induced by steric factors and that the neighboring carbonyl group also plays a role in bending toward the carbonyl side owing to an electrostatic attractive interaction. The potential surface along the path of Cdbnd N+dbnd N- bending in 2-diazopropane shows a significantly shallow profile with only 4 kcal/mol needed to bend the Cdbnd N+dbnd N- bond from 180° to 160°. Thus, the bending of the diazo group in 1 is reasonable as it is provided with all of the factors for facile bending disclosed in this investigation.

  7. Decreasing Distortion Energies without Strain: Diazo-Selective 1,3-Dipolar Cycloadditions.

    Science.gov (United States)

    Gold, Brian; Aronoff, Matthew R; Raines, Ronald T

    2016-07-15

    The diazo group has attributes that complement those of the azido group for applications in chemical biology. Here, we use computational analyses to provide insights into the chemoselectivity of the diazo group in 1,3-dipolar cycloadditions. Dipole distortion energies are responsible for ∼80% of the overall energetic barrier for these reactions. Here, we show that diazo compounds, unlike azides, provide an opportunity to decrease that barrier substantially without introducing strain into the dipolarophile. The ensuing rate enhancement is due to the greater nucleophilic character of a diazo group compared to that of an azido group, which can accommodate decreased distortion energies without predistortion. The tuning of distortion energies with substituents in a diazo compound or dipolarophile can enhance reactivity and selectivity in a predictable manner. Notably, these advantages of diazo groups are amplified in water. Our findings provide a theoretical framework that can guide the design and application of both diazo compounds and azides in "orthogonal" contexts, especially for biological investigations.

  8. Kinetic isotope effects and aliphatic diazo-compounds

    International Nuclear Information System (INIS)

    Albery, W.J.; Conway, C.W.; Hall, J.A.

    1976-01-01

    Results are reported for the variation of the rate of decomposition of ethyl diazomalonate (EDM) and diazomalonate anions with pH and for the deuterium solvent isotope effect for EDM. The shape of the pH profile is explained by successive protonations of the anions. Ethyl diazoacetate is observed as an intermediate in the decomposition of EDM. The degree of proton transfer in the EDM transition state is deduced from the solvent isotope effect and the results together with those for other aliphatic diazo-compounds are discussed in terms of the Marcus theory. (author)

  9. Decolorization of Diazo Dye Ponceau S by Fenton Process

    Directory of Open Access Journals (Sweden)

    Muhammad Muslim

    2013-12-01

    Full Text Available An attempt has been taken to decolorize and mineralize Ponceau S (PS, a diazo dye, in aqueous solution by Fenton process. Effects of solution pH, concentrations of H2O2, Fe(II and PS on the decolorization of PS have also been studied through batch experiments. About 90% decolorization was found under the optimal conditions [PS]: [H2O2]: [Fe(II] = 1:12:2 and [H2O2]/[Fe(II] = 6 at pH 2.85 in 40 minutes. The overall results revealed that mineralization was rather slower as compared with the decolorization.

  10. Diazo Compounds as Highly Tunable Reactants in 1,3-Dipolar Cycloaddition Reactions with Cycloalkynes†

    Science.gov (United States)

    McGrath, Nicholas A.

    2012-01-01

    Diazo compounds, which can be accessed directly from azides by deimidogenation, are shown to be extremely versatile dipoles in 1,3-dipolar cycloaddition reactions with a cyclooctyne. The reactivity of a diazo compound can be much greater or much less than its azide analog, and is enhanced markedly in polar-protic solvents. These reactivities are predictable from frontier molecular orbital energies. The most reactive diazo compound exhibited the highest known second-order rate constant to date for a dipolar cycloaddition with a cycloalkyne. These data provide a new modality for effecting chemoselective reactions in a biological context. PMID:23227302

  11. Gold(I)-catalyzed diazo coupling: strategy towards alkene formation and tandem benzannulation.

    Science.gov (United States)

    Zhang, Daming; Xu, Guangyang; Ding, Dong; Zhu, Chenghao; Li, Jian; Sun, Jiangtao

    2014-10-06

    A gold(I)-catalyzed cross-coupling of diazo compounds to afford tetrasubstituted alkenes has been developed by taking advantage of a trivial electronic difference between two diazo substrates. A N-heterocyclic-carbene-derived gold complex is the most effective catalyst for this transformation. Based on this new strategy, a gold(I)-initiated benzannulation has been achieved through a tandem reaction involving a diazo cross-coupling, 6π electrocyclization, and oxidative aromatization. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. 1,3-Dipolar Cycloadditions of Diazo Compounds in the Presence of Azides.

    Science.gov (United States)

    Aronoff, Matthew R; Gold, Brian; Raines, Ronald T

    2016-04-01

    The diazo group has untapped utility in chemical biology. The tolerance of stabilized diazo groups to cellular metabolism is comparable to that of azido groups. However, chemoselectivity has been elusive, as both groups undergo 1,3-dipolar cycloadditions with strained alkynes. Removing strain and tuning dipolarophile electronics yields diazo group selective 1,3-dipolar cycloadditions that can be performed in the presence of an azido group. For example, diazoacetamide but not its azido congener react with dehydroalanine residues, as in the natural product nisin.

  13. Silver-mediated direct trifluoromethoxylation of α-diazo esters via the (-)OCF3 anion.

    Science.gov (United States)

    Zha, Gao-Feng; Han, Jia-Bin; Hu, Xiao-Qian; Qin, Hua-Li; Fang, Wan-Yin; Zhang, Cheng-Pan

    2016-06-14

    Silver-mediated direct trifluoromethoxylation of α-diazo esters and ketosteroid was disclosed. The reactions of alkyl α-diazo arylacetates with AgOCF3 or CF3SO2OCF3/AgF at -30 to 10 °C under a N2 atmosphere provided α-trifluoromethoxyl arylacetates in up to 90% yield, while alkyl α-diazo vinylacetates reacting with CF3SO2OCF3/AgF or AgOCF3 afforded γ-trifluoromethoxyl α,β-unsaturated esters in up to 94% yield. The α-diazo ketosteroid was also trifluoromethoxylated under the standard reaction conditions. This protocol allows for an effective and convenient access to a large number of synthetic building blocks, which are promising in the development of new functional OCF3-molecules.

  14. 2?Diazo?1?phenyl?2?((trifluoromethyl)sulfonyl)ethan?1?one: Another Utility for Electrophilic Trifluoromethylthiolation Reactions

    OpenAIRE

    Huang, Zhongyan; Okuyama, Kenta; Wang, Chen; Tokunaga, Etsuko; Li, Xiaorui; Shibata, Norio

    2016-01-01

    Abstract 2?Diazo?1?phenyl?2?((trifluoromethyl)sulfonyl)ethan?1?one (diazo?triflone) (2) is not only a building block but also a reagent. In this study, diazo?triflone, which was originally used for the synthesis of ??lactam triflones as a trifluoromethanesulfonyl (SO2CF3) building block under catalyst?free thermal conditions, is redisclosed as an effective electrophilic trifluoromethylthiolation reagent under copper catalysis. A broad set of enamines, indoles, ??keto esters, pyrroles, and ani...

  15. Zinc-Catalyzed Synthesis of Conjugated Dienoates through Unusual Cross-Couplings of Zinc Carbenes with Diazo Compounds.

    Science.gov (United States)

    Mata, Sergio; González, María J; González, Jesús; López, Luis A; Vicente, Rubén

    2017-01-23

    Zinc-catalyzed selective cross-coupling of two carbene sources, such as vinyl diazo compounds and enynones, enabled the synthesis of conjugated dienoate derivatives. This reaction involved the unprecedented coupling of a zinc furyl carbene with vinyl diazo compounds through the γ-carbon. Alternatively, dienoates were also prepared by a commutative cross-coupling of zinc vinyl carbenes generated from cyclopropenes and simple diazo compounds. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Study of kinetics and mechanism of diazo compound reactions using nuclear chemical polarization

    International Nuclear Information System (INIS)

    Gragerov, I.P.; Levit, A.F.; Kiprianova, L.A.; Buchachenko, A.L.; Sterleva, T.G.

    1975-01-01

    It has been established that at the rate-determining steps of the radical reactions in which aniline interacts with isoamyl nitrite and substituted diazo salts interact with sodium methylate, tertiary fatty amines, or phosphinic acid, no transfer of a single electron occurs. The processes of single electron transfer do not seem to play a decisive role in the kinetics of most transformations of diazo compounds. Chemical nuclear polarization is shown to be suitable for kinetic studies of fast radical processes

  17. Fluoride-Mediated Dephosphonylation of α-Diazo-β-carbonyl Phosphonates.

    Science.gov (United States)

    Phatake, Ravindra S; Mullapudi, Venkannababu; Wakchaure, Vivek C; Ramana, Chepuri V

    2017-01-20

    The possibility of fluoride-mediated selective dephosphonylation of α-diazo-β-carbonyl phosphonates such as the Ohira-Bestmann reagent has been proposed and executed. The resulting α-diazocarbonyl intermediates undergo a (3 + 2)-cycloaddition at room temperature with conjugated olefins and benzynes. Interestingly, under the current conditions, the resulting cycloaddition products underwent either N-acylation (with excess α-diazo-β-carbonyl phosphonates) or Michael addition (with conjugated olefins).

  18. Diazo processing of LANDSAT imagery: A low-cost instructional technique

    Science.gov (United States)

    Lusch, D. P.

    1981-01-01

    Diazo processing of LANDSAT imagery is a relatively simple and cost effective method of producing enhanced renditions of the visual LANDSAT products. This technique is capable of producing a variety of image enhancements which have value in a teaching laboratory environment. Additionally, with the appropriate equipment, applications research which relys on accurate and repeatable results is possible. Exposure and development equipment options, diazo materials, and enhancement routines are discussed.

  19. Crystal structure of 2-diazo-imidazole-4,5-dicarbo-nitrile.

    Science.gov (United States)

    Parrish, Damon A; Kramer, Stephanie; Windler, G Kenneth; Chavez, David E; Leonard, Philip W

    2015-07-01

    In the title compound, C5N6, all the atoms are approximately coplanar. In the crystal, mol-ecules are packed with short contact distances of 2.885 (2) (between the diazo N atom connected to the ring and a cyano N atom on a neighboring mol-ecule) and 3.012 (2) Å (between the terminal diazo N atom and an N atom of a neighboring imidazole ring).

  20. Iron-catalyzed intermolecular cycloaddition of diazo surrogates with hexahydro-1,3,5-triazines.

    Science.gov (United States)

    Liu, Pei; Zhu, Chenghao; Xu, Guangyang; Sun, Jiangtao

    2017-09-26

    We report here an unprecedented iron-catalyzed cycloaddition reaction of diazo surrogates with hexahydro-1,3,5-triazines, providing five-membered heterocycles in moderate to high yields under mild reaction conditions. This cycloaddition features C-N and C-C bond formation using a cheap iron catalyst. Importantly, different to our former report on a gold-catalyzed system, both donor/donor and donor/acceptor diazo substrates are tolerated in this iron-catalyzed protocol.

  1. Geminal difunctionalization of α-diazo arylmethylphosphonates: synthesis of fluorinated phosphonates.

    Science.gov (United States)

    Zhou, Yujing; Zhang, Yan; Wang, Jianbo

    2016-11-08

    A general approach towards diverse fluorinated phosphonates via geminal difunctionalization reactions of α-diazo arylmethylphosphonates is described. The diazo functionality (RR'C[double bond, length as m-dash]N 2 ) is successfully converted to RR'CF 2 , RR'CHF, RR'CFBr or RR'CFNR'' 2 groups by employing different fluorination reagents. A variety of fluorinated organophosphorus compounds were readily accessed in good to excellent yields from a common type of precursor.

  2. Taming hazardous chemistry in flow: the continuous processing of diazo and diazonium compounds.

    Science.gov (United States)

    Deadman, Benjamin J; Collins, Stuart G; Maguire, Anita R

    2015-02-02

    The synthetic utilities of the diazo and diazonium groups are matched only by their reputation for explosive decomposition. Continuous processing technology offers new opportunities to make and use these versatile intermediates at a range of scales with improved safety over traditional batch processes. In this minireview, the state of the art in the continuous flow processing of reactive diazo and diazonium species is discussed. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Decolorization of Diazo Dye Ponceau S by Fenton Process

    International Nuclear Information System (INIS)

    Muslim, M.; Habib, M.A.; Islam, T.S.A.; Mahmood, A.J.; Ismail, I.M.I.

    2013-01-01

    An attempt has been taken to decolorize and mineralize Ponceau S (PS), a diazo dye, in aqueous solution by Fenton process. Effects of solution pH, concentrations of H/sub 2/O/sub 2/, Fe(II) and PS on the decolorization of PS have also been studied through batch experiments. About 90percentage decolorization was found under the optimal conditions (PS): (H/sub 2/O/sub 2/): (Fe(II)) = 1:12:2 and (H/sub 2/O/sub 2/)/(Fe(II)) = 6 at pH 2.85 in 40 minutes. The overall results revealed that mineralization was rather slower as compared with the decolorization. (author)

  4. Rapid cycloaddition of a diazo group with an unstrained dipolarophile.

    Science.gov (United States)

    Aronoff, Matthew R; Gold, Brian; Raines, Ronald T

    2016-06-01

    The cycloaddition of a diazoacetamide with ethyl 4,4,4-trifluorocrotonate proceeds with k = 0.1 M -1 s -1 . This second-order rate constant rivals those of optimized strain-promoted azide- alkyne cycloadditions, even though the reaction does not release strain. The regioselectivity and a computational distortion/interaction analysis of the reaction energetics are consistent with the formation of an N-H…F-C hydrogen bond in the transition state and the electronic character of the trifluorocrotonate. Analogous reactions with an azidoacetamide dipole or with an acrylate or crotonate dipolarophile were much slower. These findings suggest a new strategy for the design of diazo-selective reagents for chemical biology.

  5. Structural dependence of the multi-functionalized carbon nanotubes to the substituents on the grafted diazo compounds

    Science.gov (United States)

    Amiri, Rahebeh; Rasouli, Sousan; Ghasemi, Alireza; Eghbali, Babak; Mohammadi, Soutodeh

    2014-05-01

    Systematic studies on the covalent functionalization of multi-walled carbon nanotubes were performed by a series of azo molecules with different substituents. For this investigation, 4-substituted diazonium reagents have been used in the reaction with the functionalized multi-walled carbon nanotubes. We analyzed the effect of the substituted groups on the diazo component affinity in the grafting. Also, the structural differences of the final products were evaluated by visual dispersion test, UV-Vis absorption. Fourier transforms infrared, Raman, and several complementary techniques (scanning electron microscopy, thermal gravimetric analysis, and colorimetry test). Nuclear magnetic resonance spectroscopy has been used to confirm the allylic protons attached to the surface of carbon nanotubes after functionalization.

  6. Stereoselective Synthesis of Tetrasubstituted Furylalkenes via Gold-Catalyzed Cross-Coupling of Enynones with Diazo Compounds.

    Science.gov (United States)

    Liu, Pei; Sun, Jiangtao

    2017-07-07

    A stereoselective, gold-catalyzed, cross-coupling reaction of enynones with diazo compounds has been developed, affording 2-alkenylfurans in moderate to good yields with excellent E-stereoselectivity. Upon using diazo compounds as nucleophiles to trap the in situ formed gold furyl carbene, this protocol provides a novel path toward the formation of unsymmetrical tetrasubstituted alkenes.

  7. 2-Diazo-1-phenyl-2-((trifluoromethyl)sulfonyl)ethan-1-one: Another Utility for Electrophilic Trifluoromethylthiolation Reactions.

    Science.gov (United States)

    Huang, Zhongyan; Okuyama, Kenta; Wang, Chen; Tokunaga, Etsuko; Li, Xiaorui; Shibata, Norio

    2016-06-01

    2-Diazo-1-phenyl-2-((trifluoromethyl)sulfonyl)ethan-1-one (diazo-triflone) ( 2 ) is not only a building block but also a reagent. In this study, diazo-triflone, which was originally used for the synthesis of β-lactam triflones as a trifluoromethanesulfonyl (SO 2 CF 3 ) building block under catalyst-free thermal conditions, is redisclosed as an effective electrophilic trifluoromethylthiolation reagent under copper catalysis. A broad set of enamines, indoles, β-keto esters, pyrroles, and anilines were nicely transformed into corresponding trifluoromethylthio (SCF 3 ) compounds in good to high yields by diazo-triflone under copper catalysis via an electrophilic-type reaction. A coupling-type trifluoromethylthiolation reaction of aryl iodides was also realized by diazo-triflone in acceptable yields.

  8. Degradation characteristic of monoazo, diazo and anthraquinone dye by UV / H2O2 process

    Science.gov (United States)

    Abidin, Che Zulzikrami Azner; Fahmi, Muhammad Ridwan; Fazara, Md Ali Umi; Nadhirah, Siti Nurfatin

    2014-10-01

    In this study, the degradation characteristic of monoazo, diazo and anthraquinone dye by UV / H2O2 process was evaluated based on the trend of color, chemical oxygen demand (COD) and total organic carbon (TOC) removal. Three types of dyes consist of monoazo, diazo and anthraquinone dyes were used to compare the degradation mechanism of the dyes. The UV / H2O2 experiments were conducted in a laboratory scale cylindrical glass reactor operated in semi-batch mode. The UV/Vis characterization of monoazo, diazo and anthraquinone dye indicated that the rapid degradation of the dyes by UV / H2O2 process is meaningful with respect to decolourization, as a result of the azo bonds and substitute antraquinone chromophore degradation. However, this process is not efficient for aromatic amines removal. The monoazo MO was difficult to be decolorized than diazo RR120 dye, which imply that number of sulphonic groups in the dye molecules determines the reactivity with hydroxyl radical. The increased in COD removal is the evidence for oxidation and decreased in carbon content of dye molecules. TOC removal analysis shows that low TOC removal of monoazo MO and diazo RR120, as compared to anthraquinone RB19 may indicate an accumulation of by-products that are resistant to the H2O2 photolysis.

  9. Degradation characteristic of monoazo, diazo and anthraquinone dye by UV/H2O2 process

    International Nuclear Information System (INIS)

    Abidin, Che Zulzikrami Azner; Fahmi, Muhammad Ridwan; Fazara, Md Ali Umi; Nadhirah, Siti Nurfatin

    2014-01-01

    In this study, the degradation characteristic of monoazo, diazo and anthraquinone dye by UV/H 2 O 2 process was evaluated based on the trend of color, chemical oxygen demand (COD) and total organic carbon (TOC) removal. Three types of dyes consist of monoazo, diazo and anthraquinone dyes were used to compare the degradation mechanism of the dyes. The UV/H 2 O 2 experiments were conducted in a laboratory scale cylindrical glass reactor operated in semi-batch mode. The UV/Vis characterization of monoazo, diazo and anthraquinone dye indicated that the rapid degradation of the dyes by UV/H 2 O 2 process is meaningful with respect to decolourization, as a result of the azo bonds and substitute antraquinone chromophore degradation. However, this process is not efficient for aromatic amines removal. The monoazo MO was difficult to be decolorized than diazo RR120 dye, which imply that number of sulphonic groups in the dye molecules determines the reactivity with hydroxyl radical. The increased in COD removal is the evidence for oxidation and decreased in carbon content of dye molecules. TOC removal analysis shows that low TOC removal of monoazo MO and diazo RR120, as compared to anthraquinone RB19 may indicate an accumulation of by-products that are resistant to the H 2 O 2 photolysis

  10. The labelling of monoclonal antibody with 211At via diazo salts of aromatic diamine

    International Nuclear Information System (INIS)

    Jin Jiannan; Zhang Shuyuan; Zhou Maolun; Liu Ning

    1992-01-01

    A method was described for labelling CEA monoclonal antibody (CEA-McAb) with the α-emitting nuclide 211 At via diazo salts of p-phenylenediamine or benzidine. Aromatic diamine were transformed into diazo salts and subsequently both 211 At and CEA-McAb react with diazo salts to produce 211 At-CEA-McAb conjugates. The reaction and purification required about 2.5 h. Sephadex G-75 column was used to separate the labelled CEA-McAb from reactive products and the labelling yield was at least 30% of the initial activity of 211 At. The specific activity of 211 At-CEA-McAb (2.2-3.7) x 10 4 Bq/μg(McAb) could be achieved. The results of tissue distribution of 211 At in mice showed that 211 At-CEA-McAb conjugates were stable in vivo

  11. Studies of a Diazo Cyclopropanation Strategy for the Total Synthesis of (-)-Lundurine A.

    Science.gov (United States)

    Huang, Hong-Xiu; Jin, Shuai-Jiang; Gong, Jin; Zhang, Dan; Song, Hao; Qin, Yong

    2015-09-14

    The bioactive Kopsia alkaloids lundurines A-D are the only natural products known to contain indolylcyclopropane. Achieving their syntheses can provide important insights into their biogenesis, as well as novel synthetic routes for complex natural products. Asymmetric total synthesis of (-)-lundurine A has previously been achieved through a Simmons-Smith cyclopropanation strategy. Here, the total synthesis of (-)-lundurine A was carried out using a metal-catalyzed diazo cyclopropanation strategy. In order to avoid a carbene CH insertion side reaction during cyclopropanation of α-diazo- carboxylates or cyanides, a one-pot, copper-catalyzed Bamford-Stevens diazotization/diazo decomposition/cyclopropanation cascade was developed, involving hydrazone. This approach simultaneously generates the C/D/E ring system and the two chiral quaternary centers at C2 and C7. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Asymmetric Catalysis with Organic Azides and Diazo Compounds Initiated by Photoinduced Electron Transfer.

    Science.gov (United States)

    Huang, Xiaoqiang; Webster, Richard D; Harms, Klaus; Meggers, Eric

    2016-09-28

    Electron-acceptor-substituted aryl azides and α-diazo carboxylic esters are used as substrates for visible-light-activated asymmetric α-amination and α-alkylation, respectively, of 2-acyl imidazoles catalyzed by a chiral-at-metal rhodium-based Lewis acid in combination with a photoredox sensitizer. This novel proton- and redox-neutral method provides yields of up to 99% and excellent enantioselectivities of up to >99% ee with broad functional group compatibility. Mechanistic investigations suggest that an intermediate rhodium enolate complex acts as a reductive quencher to initiate a radical process with the aryl azides and α-diazo carboxylic esters serving as precursors for nitrogen and carbon-centered radicals, respectively. This is the first report on using aryl azides and α-diazo carboxylic esters as substrates for asymmetric catalysis under photoredox conditions. These reagents have the advantage that molecular nitrogen is the leaving group and sole byproduct in this reaction.

  13. Copper-Catalyzed Oxy-Alkynylation of Diazo Compounds with Hypervalent Iodine Reagents.

    Science.gov (United States)

    Hari, Durga Prasad; Waser, Jerome

    2016-02-24

    Alkynes have found widespread applications in synthetic chemistry, biology, and materials sciences. In recent years, methods based on electrophilic alkynylation with hypervalent iodine reagents have made acetylene synthesis more flexible and efficient, but they lead to the formation of one equivalent of an iodoarene as side-product. Herein, a more efficient strategy involving a copper-catalyzed oxy-alkynylation of diazo compounds with ethynylbenziodoxol(on)e (EBX) reagents is described, which proceeds with generation of nitrogen gas as the only waste. This reaction is remarkable for its broad scope in both EBX reagents and diazo compounds. In addition, vinyl diazo compounds gave enynes selectively as single geometric isomers. The functional groups introduced during the transformation served as easy handles to access useful building blocks for synthetic and medicinal chemistry.

  14. Refractive index modulation in polymer film doped with diazo Meldrum's acid

    Science.gov (United States)

    Zanutta, Alessio; Villa, Filippo; Bertarelli, Chiara; Bianco, Andrea

    2016-08-01

    Diazo Meldrum's acid undergoes a photoreaction induced by UV light and it is used as photosensitizer in photoresists. Upon photoreaction, a change in refractive index occurs, which makes this system interesting for volume holography. We report on the sublimation effect at room temperature and the effect of photoirradiation on the refractive index in thin films of CAB (Cellulose acetate butyrate) doped with different amount of diazo Meldrum's acid. A net modulation of the refractive index of 0.01 is achieved with 40% of doping ratio together with a reduction of the film thickness.

  15. Diazo Esters as Dienophiles in Intramolecular (4 + 2) Cycloadditions: Computational Explorations of Mechanism.

    Science.gov (United States)

    Duan, Abing; Yu, Peiyuan; Liu, Fang; Qiu, Huang; Gu, Feng Long; Doyle, Michael P; Houk, K N

    2017-02-22

    The first experimental examples of Diels-Alder (DA) reactions of diazo compounds as heterodienophiles with dienes have been studied with density functional theory (DFT) using the M06-2X functional. For comparison, the reactivities of diazo esters as dienophiles or 1,3-dipoles with 1,3-dienes in intermolecular model systems have been analyzed by the distortion/interaction model. The 1,3-dipolar cycloaddition is strongly favored for the intermolecular system. The intramolecular example is unique because the tether strongly favors the (4 + 2) cycloaddition.

  16. Silver-Catalyzed Cyclopropanation of Alkenes Using N-Nosylhydrazones as Diazo Surrogates.

    Science.gov (United States)

    Liu, Zhaohong; Zhang, Xinyu; Zanoni, Giuseppe; Bi, Xihe

    2017-12-15

    An efficient silver-catalyzed [2 + 1] cyclopropanation of sterically hindered internal alkenes with diazo compounds in which room-temperature-decomposable N-nosylhydrazones are used as diazo surrogates is reported. The unexpected unique catalytic activity of silver was ascribed to its dual role as a Lewis acid activating alkene substrates and as a transition metal forming silver carbenoids. A wide range of internal alkenes, including challenging diarylethenes, were suitable for this protocol, thereby affording a variety of cyclopropanes with high efficiency in a stereoselective manner under mild conditions.

  17. Covalent Chemical 5'-Functionalization of RNA with Diazo Reagents.

    Science.gov (United States)

    Gampe, Christian M; Hollis-Symynkywicz, Micah; Zécri, Frédéric

    2016-08-22

    Functionalization of RNA at the 5'-terminus is important for analytical and therapeutic purposes. Currently, these RNAs are synthesized de novo starting with a chemically functionalized 5'-nucleotide, which is incorporated into RNA using chemical synthesis or biochemical techniques. Methods for direct chemical modification of native RNA would provide an attractive alternative but are currently underexplored. Herein, we report that diazo compounds can be used to selectively alkylate the 5'-phosphate of ribo(oligo)nucleotides to give RNA labelled through a native phosphate ester bond. We applied this method to functionalize oligonucleotides with biotin and an orthosteric inhibitor of the eukaryotic initiation factor 4E (eIF4E), an enzyme involved in mRNA recognition. The modified RNA binds to eIF4E, demonstrating the utility of this labelling technique to modulate biological activity of RNA. This method complements existing techniques and may be used to chemically introduce a broad range of functional handles at the 5'-end of RNA. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Adsorbent cartridge for the exhaust of diazo process machines

    International Nuclear Information System (INIS)

    Michlin, N.; Thies, E.J.

    1982-01-01

    A disposable cartridge filled with a chemical composition that acts as an adsorbent for ammonia vapor is adapted to be used in connection with a diazo process printing machine having a vacuum exhausted chamber. Exhaust from the chamber is passed through the cartridge to remove the noxious ammonia vapors and then is vented into the atmosphere. The cartridge is housed in an elongated rectangular cardboard box having three end flaps formed at each of its opposed open ends. Two opposed flaps of each set are formed with central holes and a plastic screen section adhered between these flaps to retain and allow access to the center section of the box which contains the adsorbent chemical. The center end flaps have knock-outs or tear strips that allow holes to be formed in their centers. These center end flaps cover the screens during shipment and when the cartridge is ready for use the center sections of these end flaps are knocked-out to allow the machine exhaust to be vented into and out of the cartridge

  19. Crystal structure of rubidium methyl-diazo-tate.

    Science.gov (United States)

    Grassl, Tobias; Korber, Nikolaus

    2017-02-01

    The title compound, Rb + ·H 3 CN 2 O - , has been crystallized in liquid ammonia as a reaction product of the reductive ammonolysis of the natural compound streptozocin. Elemental rubidium was used as reduction agent as it is soluble in liquid ammonia, forming a blue solution. Reductive bond cleavage in biogenic materials under kinetically controlled conditions offers a new approach to gain access to sustainably produced raw materials. The anion is nearly planar [dihedral angle O-N-N-C = -0.4 (2)°]. The Rb + cation has a coordination number of seven, and coordinates to five anions. One anion is bound via both its N atoms, one by both O and N, two anions are bound by only their O atoms, and the last is bound via the N atom adjacent to the methyl group. The diazo-tate anions are bridged by cations and do not exhibit any direct contacts with each other. The cations form corrugated layers that propagate in the (-101) plane.

  20. A Versatile Route to Unstable Diazo Compounds via Oxadiazolines and their Use in Aryl–Alkyl Cross‐Coupling Reactions

    Science.gov (United States)

    Greb, Andreas; Poh, Jian‐Siang; Greed, Stephanie; Battilocchio, Claudio; Pasau, Patrick; Blakemore, David C.

    2017-01-01

    Abstract Coupling of readily available boronic acids and diazo compounds has emerged recently as a powerful metal‐free carbon–carbon bond forming method. However, the difficulty in forming the unstable diazo compound partner in a mild fashion has hitherto limited their general use and the scope of the transformation. Here, we report the application of oxadiazolines as precursors for the generation of an unstable family of diazo compounds using flow UV photolysis and their first use in divergent protodeboronative and oxidative C(sp2)−C(sp3) cross‐coupling processes, with excellent functional‐group tolerance. PMID:29088512

  1. Synergistic Diazo-OH Insertion/Conia-Ene Cascade Catalysis for the Stereoselective Synthesis of γ-Butyrolactones and Tetrahydrofurans.

    Science.gov (United States)

    Hunter, Arianne C; Schlitzer, Steven C; Sharma, Indrajeet

    2016-11-02

    A novel and highly efficient diazo-OH insertion/Conia-ene cascade reaction of readily available homopropargylic acids and alcohols with diazo carbonyl compounds is described. The cascade reaction involves a synergistic Rh/Ag/Au catalyst cocktail and proceeds instantly with a variety of substituted diazo compounds and acids/alcohols to provide functionalized γ-butyrolactones and tetrahydrofurans with complete regio- and stereoselectivity. The unprecedented rate-enhancement, complete stereoselectivity, and the enabling of new Conia-ene cyclizations suggest a concerted [4+1]-cycloaddition reaction pathway under synergistic (Rh/Ag/Au)-catalysis conditions. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Reações de inserção intramolecular de diazo compostos polifuncionais catalisadas por ródio(II: síntese de oxetan-3-ona-2-carboxilato e outros heterociclos funcionalizados Rhodium(II-catalysed intramolecular insertion reaction of multifunctional diazo compounds: synthesis of oxetan-3-one-2-carboxilate and other heterocycles

    Directory of Open Access Journals (Sweden)

    Albert Padwa

    1999-12-01

    Full Text Available gamma-Hydroxy-alpha-diazo-beta-ketoesters are key intermediates in the chemistry of penicilin-based antibiotics and natural products. The method developed here for the synthesis of ethyl 2-diazo-4-hydroxy-3-oxo-butanoate 17 (in two steps from the diazo mercurial 2 compares very favorably with those reported in the literature for similar compounds. The Rh2(OAc4-mediated intramolecular OH-insertion reaction of the diazo hydroxy ester 17 was investigated, furnishing the oxetan-3-one-2-carboxilate 18 in good yield. When the diazo ester lacks a free hydroxyl group as in the case of the phenoxy diazo ester 11 an intramolecular CH-insertion takes place, affording the 2H-chromene 20 in almost quantitative yield. The behavior of other functionalized diazo esters towards Rh2(OAc4 was also investigated.

  3. Fe(HSO4)3 as an Efficient Catalyst for Diazotization and Diazo Coupling Reactions

    International Nuclear Information System (INIS)

    Rahimizadeh, Mohammad; Eshghi, Hossein; Shiri, Ali; Ghadamyari, Zohreh; Matin, Maryam M.; Pordeli, Parvaneh; Oroojalian, Fatemeh

    2012-01-01

    Diazo coupling reactions of aromatic amines with 2-naphthol in a green, efficient and easy procedure is described. Ferric hydrogensulfate catalyses this reaction in water at room temperature and short reaction time with high yields. The antibacterial activities of the synthesized compounds against four pathogenic bacteria are also investigated

  4. Single-step azide introduction in proteins via an aqueous diazo transfer

    NARCIS (Netherlands)

    van Dongen, S.F.M.; Teeuwen, R.L.M.; Nallani, M.; van Berkel, S.S.; Cornelissen, J.J.L.M.; Nolte, R.J.M.; van Hest, J.C.M.

    The controlled introduction of azides in proteins provides targetable handles for selective protein manipulation. We present here an efficient diazo transfer protocol that can be applied in an aqueous solution, leading to the facile introduction of azides in the side chains of lysine residues and at

  5. Single-Step Azide Introduction in Proteins via an Aqueous Diazo Transfer

    NARCIS (Netherlands)

    van Dongen, Stijn; Teeuwen, R.L.M.; Nallani, Madhavan; van Berkel, S.S; Cornelissen, Jeroen Johannes Lambertus Maria; Nolte, Roeland; van Hest, Jan

    2009-01-01

    The controlled introduction of azides in proteins provides targetable handles for selective protein manipulation. We present here an efficient diazo transfer protocol that can be applied in an aqueous solution, leading to the facile introduction of azides in the side chains of lysine residues and at

  6. Rh(III-Catalyzed, Highly Selectively Direct C–H Alkylation of Indoles with Diazo Compounds

    Directory of Open Access Journals (Sweden)

    Kang Wan

    2016-06-01

    Full Text Available Rh(III-catalyzed regioselective alkylation of indoles with diazo compounds as a highly efficient and atom-economic protocol for the synthesis of alkyl substituted indoles has been developed. The reaction could proceed under mild conditions and afford a series of desired products in good to excellent yields.

  7. Rhodium(II)-Catalyzed Asymmetric Sulfur(VI) Reduction of Diazo Sulfonylamidines

    OpenAIRE

    Selander, Nicklas; Fokin, Valery V.

    2012-01-01

    Diazo sulfonylamidines readily undergo enantioselective oxygen transfer from sulfur to carbon atom in the presence of chiral rhodium(II) carboxylates resulting in chiral sulfinylamidines. This unusual asymmetric atom transfer “reduction” occurs rapidly under mild conditions, and sulfinylamidines are obtained in excellent yield.

  8. Mixed-ligand complexes of ruthenium(II) incorporating a diazo ...

    Indian Academy of Sciences (India)

    Unknown

    Dedicated to the memory of the late Professor Bhaskar G Maiya. *For correspondence. Mixed-ligand complexes of ruthenium(II) incorporating a diazo ligand: Synthesis .... water (1 : 1) for 5 h to give a dark red solution. The solution was cooled to room temperature. After eva- poration of the solvent, the solid was collected,.

  9. Efficient Synthesis of Spirobarbiturates and Spirothiobarbiturates Bearing Cyclopropane Rings by Rhodium(II)-Catalyzed Reactions of Cyclic Diazo Compounds

    International Nuclear Information System (INIS)

    Wang, Xue; Lee, Yong Rok

    2013-01-01

    Rhodium(II)-catalyzed reactions of cyclic diazo compounds derived from barbituric acid and thiobarbituric acid with a variety of styrene moieties were examined. These reactions provide rapid synthetic routes to the preparations of spirobarbiturates and spirothiobarbiturates bearing cyclopropane rings

  10. Efficient Synthesis of Spirobarbiturates and Spirothiobarbiturates Bearing Cyclopropane Rings by Rhodium(II)-Catalyzed Reactions of Cyclic Diazo Compounds

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xue; Lee, Yong Rok [Yeungnam Univ., Gyeongsan (Korea, Republic of)

    2013-06-15

    Rhodium(II)-catalyzed reactions of cyclic diazo compounds derived from barbituric acid and thiobarbituric acid with a variety of styrene moieties were examined. These reactions provide rapid synthetic routes to the preparations of spirobarbiturates and spirothiobarbiturates bearing cyclopropane rings.

  11. A Versatile Room-Temperature Route to Di- and Trisubstituted Allenes Using Flow-Generated Diazo Compounds**

    Science.gov (United States)

    Poh, Jian-Siang; Tran, Duc N; Battilocchio, Claudio; Hawkins, Joel M; Ley, Steven V

    2015-01-01

    A copper-catalyzed coupling reaction between flow-generated unstabilized diazo compounds and terminal alkynes provides di- and trisubstituted allenes. This extremely mild and rapid transformation is highly tolerant of several functional groups. PMID:26013774

  12. Rh(III)-Catalyzed C-H Activation of Benzoylacetonitriles and Tandem Cyclization with Diazo Compounds to Substituted Benzo[ de]chromenes.

    Science.gov (United States)

    Fang, Feifei; Zhang, Chunmei; Zhou, Chaofan; Li, Yazhou; Zhou, Yu; Liu, Hong

    2018-04-06

    Rh (III)-catalyzed C-H activation of benzoylacetonitriles in coupling with diazo compounds was developed to synthesize diversified substituted benzo[ de]chromenes via a formal (4 + 2) cycloaddition with a diazo compound and subsequent tandem (4 + 2) cycloaddition with another diazo compound. Intriguingly, synthesis of substituted benzo[ de]chromenes and their decarboxylation products could be realized by controlling the reaction conditions. These reactions have a broad range of substrates, moderate to good yields, and high regioselectivity.

  13. Rh(III)-Catalyzed Synthesis of N-Unprotected Indoles from Imidamides and Diazo Ketoesters via C-H Activation and C-C/C-N Bond Cleavage.

    Science.gov (United States)

    Qi, Zisong; Yu, Songjie; Li, Xingwei

    2016-02-19

    The synthesis of N-unprotected indoles has been realized via Rh(III)-catalyzed C-H activation/annulation of imidamides with α-diazo β-ketoesters. The reaction occurs with the release of an amide coproduct, which originates from both the imidamide and the diazo as a result of C═N cleavage of the imidamide and C-C(acyl) cleavage of the diazo. A rhodacyclic intermediate has been isolated and a plausible mechanism has been proposed.

  14. Alkyl halide-free heteroatom alkylation and epoxidation facilitated by a recyclable polymer-supported oxidant for the in-flow preparation of diazo compounds.

    Science.gov (United States)

    Nicolle, Simon M; Hayes, Christopher J; Moody, Christopher J

    2015-03-16

    Highly reactive metal carbenes, generated from simple ketones via diazo compounds, including diazo-amides and -phosphonates, using a recyclable reagent in-flow, are transient but versatile electrophiles for heteroatom alkylation reactions and for epoxide formation. The method produces no organic waste, with the only by-products being water, KI and nitrogen, without the attendant hazards of isolation of intermediate diazo compounds. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Ru(II)-Catalyzed Cross-Coupling of Cyclopropenes with Diazo Compounds: Formation of Olefins from Two Different Carbene Precursors.

    Science.gov (United States)

    Wang, Bo; Yi, Heng; Zhang, Hang; Sun, Tong; Zhang, Yan; Wang, Jianbo

    2018-01-19

    Formal carbene dimerization is a convergent method for the synthesis of alkenes. Herein, we report a Ru(II)-catalyzed carbene dimerization of cyclopropenes and diazo compounds. The yields are up to 97% and the stereoselectivity are up to >20:1. Mechanistically, it has been experimentally demonstrated that the catalyst reacts with cyclopropene first to generate a Ru(II)-carbene species, which is attacked by nucleophilic diazo substrate, followed by dinitrogen extrusion to form the double bond.

  16. Improving multilayer films endurance by photoinduced interaction between Dawson-type polyoxometalate and diazo resin

    International Nuclear Information System (INIS)

    Zhang Jishuang; Xu Lin; Cui Yang; Cao Weixiao; Li Zhuang

    2005-01-01

    A composite multilayer film constructed of Dawson anion [P 2 Mo 18 O 62 ] 6- and diazo resin (DR) was prepared by the electrostatic layer-by-layer (LbL) self-assembly method. The film could be stabilized by the photoinduced interaction between Dawson anion and diazo resin. IR spectra and X-ray photoelectron spectra revealed the possible occurrence of partial transformation from electrostatic interaction to covalent interaction between layers of the film after irradiation by UV light. Such transformation evidently increases the endurance of the film, which was demonstrated by AFM images and etching experiments with organic solvent. This study provides a new route to stabilze the polyoxometalate-based multilayer film by virtue of the photoinduced reaction with photosensitive polymer

  17. Improving multilayer films endurance by photoinduced interaction between Dawson-type polyoxometalate and diazo resin

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Jishuang [Department of Chemistry, Northeast Normal University, Renmin Street 5268, Changchun 130024 (China); Xu Lin [Department of Chemistry, Northeast Normal University, Renmin Street 5268, Changchun 130024 (China)]. E-mail: linxu@nenu.edu.cn; Cui Yang [Department of Chemistry, Northeast Normal University, Renmin Street 5268, Changchun 130024 (China); Cao Weixiao [College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China); Li Zhuang [Changchun Institute of Applied Chemistry, Academia Sinica, Changchun 130022 (China)

    2005-03-15

    A composite multilayer film constructed of Dawson anion [P{sub 2}Mo{sub 18}O{sub 62}]{sup 6-} and diazo resin (DR) was prepared by the electrostatic layer-by-layer (LbL) self-assembly method. The film could be stabilized by the photoinduced interaction between Dawson anion and diazo resin. IR spectra and X-ray photoelectron spectra revealed the possible occurrence of partial transformation from electrostatic interaction to covalent interaction between layers of the film after irradiation by UV light. Such transformation evidently increases the endurance of the film, which was demonstrated by AFM images and etching experiments with organic solvent. This study provides a new route to stabilze the polyoxometalate-based multilayer film by virtue of the photoinduced reaction with photosensitive polymer.

  18. Synthesis of Polycyclic Ring Systems Using Transition Metal Catalyzed Cyclizations of Diazo Alkynyl Ketones

    Directory of Open Access Journals (Sweden)

    Albert Padwa

    2000-12-01

    Full Text Available The rhodium(II-catalyzed reaction of α-diazo ketones bearing tethered alkyne units represents a new and useful method for the construction of a variety of substituted cyclopentenones. The process proceeds by addition of the rhodium-stabilized carbenoid onto the acetylenic π-bond to give a vinyl carbenoid intermediate. The resulting rhodium complex undergoes a wide assortment of reactions including cyclopropanation, 1,2-hydrogen migration, CH-insertion, addition to tethered alkynes and ylide formation. When 2-alkynyl-2-diazo-3-oxobutanoates were treated with a Rh(II-catalyst, furo[3,4-c]furans were formed in excellent yield.

  19. Rhodium(III)- and iridium(III)-catalyzed C7 alkylation of indolines with diazo compounds.

    Science.gov (United States)

    Ai, Wen; Yang, Xueyan; Wu, Yunxiang; Wang, Xuan; Li, Yuanchao; Yang, Yaxi; Zhou, Bing

    2014-12-22

    A Rh(III)-catalyzed procedure for the C7-selective C-H alkylation of various indolines with α-diazo compounds at room temperature is reported. The advantages of this process are: 1) simple, mild, and pH-neutral reaction conditions, 2) broad substrate scope, 3) complete regioselectivity, 4) no need for an external oxidant, and 5) N2 as the sole byproduct. Furthermore, alkylation and bis-alkylation of carbazoles at the C1 and C8 positions have also been developed. More significantly, for the first time, a successful Ir(III)-catalyzed intermolecular insertion of arene C-H bonds into α-diazo compounds is reported. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Reaction of Diazo Compounds with Difluorocarbene: An Efficient Approach towards 1,1-Difluoroolefins.

    Science.gov (United States)

    Zhang, Zhikun; Yu, Weizhi; Wu, Chenggui; Wang, Chengpeng; Zhang, Yan; Wang, Jianbo

    2016-01-04

    A transition-metal-free difluoromethylenation of diazo compounds that proceeds under mild conditions has been developed and is based on the use of TMSCF2 Br as the difluoromethylene source and tetrabutylammonium bromide (TBAB) as the promoter. The chemoselective formal carbene dimerization reaction is achieved owing to the electronic properties and the relative stability of the difluorocarbene intermediate. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. 2-Diazo-1-(4-hydroxyphenyl)ethanone: a versatile photochemical and synthetic reagent.

    Science.gov (United States)

    Senadheera, Sanjeewa N; Evans, Anthony S; Toscano, John P; Givens, Richard S

    2014-02-01

    α-Diazo arylketones are well-known substrates for Wolff rearrangement to phenylacetic acids through a ketene intermediate by either thermal or photochemical activation. Likewise, α-substituted p-hydroxyphenacyl (pHP) esters are substrates for photo-Favorskii rearrangements to phenylacetic acids by a different pathway that purportedly involves a cyclopropanone intermediate. In this paper, we show that the photolysis of a series of α-diazo-p-hydroxyacetophenones and p-hydroxyphenacyl (pHP) α-esters both generate the identical rearranged phenylacetates as major products. Since α-diazo-p-hydroxyacetophenone (1a, pHP N2) contains all the necessary functionalities for either Wolff or Favorskii rearrangement, we were prompted to probe this intriguing mechanistic dichotomy under conditions favorable to the photo-Favorskii rearrangement, i.e., photolysis in hydroxylic media. An investigation of the mechanism for conversion of 1a to p-hydroxyphenyl acetic acid (4a) using time-resolved infrared (TRIR) spectroscopy clearly demonstrates the formation of a ketene intermediate that is subsequently trapped by solvent or nucleophiles. The photoreaction of 1a is quenched by oxygen and sensitized by triplet sensitizers and the quantum yields for 1a-c range from 0.19 to a robust 0.25. The lifetime of the triplet, determined by Stern-Volmer quenching, is 31 ns with a rate for appearance of 4a of k = 7.1 × 10(6) s(-1) in aq. acetonitrile (1 : 1 v : v). These studies establish that the primary rearrangement pathway for 1a involves ketene formation in accordance with the photo-Wolff rearrangement. Furthermore we have also demonstrated the synthetic utility of 1a as an esterification and etherification reagent with a variety of substituted α-diazo-p-hydroxyacetophenones, using them as synthons for efficiently coupling it to acids and phenols to produce pHP protect substrates.

  2. 2-Diazo-1-(4-hydroxyphenyl)ethanone: A Versatile Photochemical and Synthetic Reagenta

    Science.gov (United States)

    Senadheera, Sanjeewa N.; Evans, Anthony S.; Toscano, John P.; Givens, Richard S.

    2014-01-01

    α-Diazo arylketones are well-known substrates for Wolff rearrangement to phenylacetic acids through a ketene intermediate by either thermal or photochemical activation. Likewise, α-substituted p-hydroxyphenacyl (pHP) esters are substrates for photo-Favorskii rerrangements to phenylacetic acids by a different pathway that purportedly involves a cyclopropanone intermediate. In this paper, we show that the photolysis of a series of α-diazo-p-hydroxyacetophenones and p-hydroxyphenacyl (pHP) α-esters both generate the identical rearranged phenylacetates as major products. Since α-diazo-p-hydroxyacetophenone (1a, pHP N2) contains all the necessary functionalities for either Wolff or Favorskii rearrangement, we were prompted to probe this intriguing mechanistic dichotomy under conditions favorable to the photo-Favorskii reangement, i.e., photolysis in hydroxylic media. An investigation of the mechanism for conversion of 1a to p-hydroxyphenyl acetic acid (4a) using time-resolved infrared (TRIR) spectroscopy clearly demonstrates the formation of a ketene intermediate that is subsequently trapped by solvent or nucleophiles. The photoreaction of 1a is quenched by oxygen and sensitized by triplet sensitizers and the quantum yields for 1a–c range from 0.19 to a robust 0.25. The lifetime of the triplet, determined by Stern-Volmer quenching, is 15 ns with a rate for appearance of 4a of k = 7,1 × 106 s−1 in aq. acetonitrile (1:1 v:v). These studies establish that the primary rearrangement pathway for 1a involves ketene formation in accordance with the photo-Wolff rearrangement. Furthermore we have also demonstrated the synthetic utility of 1a as an esterification and etherification reagent with a variety of substituted α-diazo-p-hydroxyacetophenones, using them as synthons for efficiently coupling it to acids and phenols to produce pHP protect substrates. PMID:24305682

  3. Stereoselective Synthesis of Tetrahydroindolizines through the Catalytic Formation of Pyridinium Ylides from Diazo Compounds.

    Science.gov (United States)

    Day, Jonathan; McKeever-Abbas, Ben; Dowden, James

    2016-05-04

    Commercially available iron(III) and copper(I) complexes catalyzed multicomponent cycloaddition reactions between diazo compounds, pyridines, and electrophilic alkenes to give alkaloid-inspired tetrahydroindolizidines in high yield with high diastereoselectivity. Hitherto, the catalytic formation of versatile pyridinium ylides from metal carbenes has been poorly developed; the broad utility demonstrated herein sets the stage for the invention of further multicomponent reactions in future. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Vibrational correlation between conjugated carbonyl and diazo modes studied by single- and dual-frequency two-dimensional infrared spectroscopy

    Science.gov (United States)

    Maekawa, Hiroaki; Sul, Soohwan; Ge, Nien-Hui

    2013-08-01

    We have applied infrared three-pulse photon echo and single- and dual-frequency 2D IR spectroscopy to the ester Cdbnd O and diazo Ndbnd N stretching modes in ethyl diazoacetate (EDA), and investigated their vibrational frequency fluctuations and correlation. The two modes exhibit different vibrational dynamics and 2D lineshape, which are well simulated by frequency-frequency correlation functions (FFCFs) with two decaying components. Although the FT IR spectrum shows a single Cdbnd O band, absolute magnitude 2D IR nonrephasing spectrum displays spectral signatures supporting the presence of cis and trans conformations. The cross-peak inclined toward the anti-diagonal in the dual-frequency 2D IR spectrum, indicating that the frequency fluctuations of the two modes are anticorrelated. This behavior is attributed to anticorrelated change in the bond orders when solvent and structural fluctuations causes EDA to adopt a different mixture of the two dominant resonance structures. The effects of cross FFCF on the cross-peak line shape are discussed.

  5. Vibrational correlation between conjugated carbonyl and diazo modes studied by single- and dual-frequency two-dimensional infrared spectroscopy

    International Nuclear Information System (INIS)

    Maekawa, Hiroaki; Sul, Soohwan; Ge, Nien-Hui

    2013-01-01

    Highlights: ► Vibrational dynamics of conjugated C=O and N=N modes of ethyl diazoacetate was studied. ► Their frequency–frequency correlation functions are different. ► The dual-frequency 2D IR spectrum indicates anticorrelated frequency fluctuations. ► Correlation effects on dual-frequency 2D IR spectra are discussed. ► The existence of cis and trans conformers is revealed in 2D IR spectra. - Abstract: We have applied infrared three-pulse photon echo and single- and dual-frequency 2D IR spectroscopy to the ester C=O and diazo N=N stretching modes in ethyl diazoacetate (EDA), and investigated their vibrational frequency fluctuations and correlation. The two modes exhibit different vibrational dynamics and 2D lineshape, which are well simulated by frequency–frequency correlation functions (FFCFs) with two decaying components. Although the FT IR spectrum shows a single C=O band, absolute magnitude 2D IR nonrephasing spectrum displays spectral signatures supporting the presence of cis and trans conformations. The cross-peak inclined toward the anti-diagonal in the dual-frequency 2D IR spectrum, indicating that the frequency fluctuations of the two modes are anticorrelated. This behavior is attributed to anticorrelated change in the bond orders when solvent and structural fluctuations causes EDA to adopt a different mixture of the two dominant resonance structures. The effects of cross FFCF on the cross-peak line shape are discussed

  6. Vibrational correlation between conjugated carbonyl and diazo modes studied by single- and dual-frequency two-dimensional infrared spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Maekawa, Hiroaki; Sul, Soohwan [Department of Chemistry, University of California at Irvine, Irvine, CA 92697-2025 (United States); Ge, Nien-Hui, E-mail: nhge@uci.edu [Department of Chemistry, University of California at Irvine, Irvine, CA 92697-2025 (United States)

    2013-08-30

    Highlights: ► Vibrational dynamics of conjugated C=O and N=N modes of ethyl diazoacetate was studied. ► Their frequency–frequency correlation functions are different. ► The dual-frequency 2D IR spectrum indicates anticorrelated frequency fluctuations. ► Correlation effects on dual-frequency 2D IR spectra are discussed. ► The existence of cis and trans conformers is revealed in 2D IR spectra. - Abstract: We have applied infrared three-pulse photon echo and single- and dual-frequency 2D IR spectroscopy to the ester C=O and diazo N=N stretching modes in ethyl diazoacetate (EDA), and investigated their vibrational frequency fluctuations and correlation. The two modes exhibit different vibrational dynamics and 2D lineshape, which are well simulated by frequency–frequency correlation functions (FFCFs) with two decaying components. Although the FT IR spectrum shows a single C=O band, absolute magnitude 2D IR nonrephasing spectrum displays spectral signatures supporting the presence of cis and trans conformations. The cross-peak inclined toward the anti-diagonal in the dual-frequency 2D IR spectrum, indicating that the frequency fluctuations of the two modes are anticorrelated. This behavior is attributed to anticorrelated change in the bond orders when solvent and structural fluctuations causes EDA to adopt a different mixture of the two dominant resonance structures. The effects of cross FFCF on the cross-peak line shape are discussed.

  7. 3-Diazo-N-[(2S-1-hydroxypropan-2-yl]-2-oxopropanamide

    Directory of Open Access Journals (Sweden)

    Xiao-na Chen

    2011-05-01

    Full Text Available In the title compound, C6H9N3O3, the 3-diazo-2-oxopropanamide section of the molecule is nearly planar, with a maximum deviation of 0.025 (1 Å from the mean plane of its constituent atoms. The diazo C=N=N angle is 178.0 (3°. In the crystal, pairs of intermolecular O—H...O and N—H...O hydrogen bonds link the molecules into infinite double chains along the [100] direction. The double chains are additionally stabilized by weak C—H...O contacts with C...O distances of 3.039 (3 Å. Neighboring double chains in turn interact with each other through π–π stacking interactions [centroid–centroid distance of the 3-diazo-2-oxopropanamide units = 3.66 (6 Å] to form infinite stacks along the b axis. Molecules from neighboring stacks interdigitate with each other in the c-axis direction, thus leading to an interwoven three-dimensional network held together by O—H...O, N—H...O and C—H...O interactions and π–π stacking.

  8. Azidoimidazolinium Salts: Safe and Efficient Diazo-transfer Reagents and Unique Azido-donors.

    Science.gov (United States)

    Kitamura, Mitsuru

    2017-07-01

    2-Azido-1,3-dimethylimidazolinium chloride (ADMC) and its corresponding hexafluorophosphate (ADMP) were found to be efficient diazo-transfer reagents to various organic compounds. ADMC was prepared by the reaction of 2-chloro-1,3-dimethylimidazolinium chloride (DMC) and sodium azide. ADMP was isolated as a crystal having good thermal stability and low explosibility. ADMC and ADMP reacted with 1,3-dicarbonyl compounds under mild basic conditions to give 2-diazo-1,3-dicarbonyl compounds in high yields, which were easily isolated in virtue of the high water solubility of the by-products. ADMP showed high diazo-transfer ability to primary amines even in the absence of metal salt such as Cu(II). Using this diazotization approach, various alkyl/aryl azides were directly obtained from their corresponding primary amines in high yields. Furthermore, naphthols reacted with ADMC to give the corresponding diazonaphthoquinones in good to high yields. In addition, 2-azido-1,3-dimethylimidazolinium salts were employed as azide-transfer and migratory amidation reagents. © 2017 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Reações de inserção intramolecular de diazo compostos polifuncionais catalisadas por ródio(II): síntese de oxetan-3-ona-2-carboxilato e outros heterociclos funcionalizados Rhodium(II)-catalysed intramolecular insertion reaction of multifunctional diazo compounds: synthesis of oxetan-3-one-2-carboxilate and other heterocycles

    OpenAIRE

    Albert Padwa; Marcus Mandolesi Sá

    1999-01-01

    gamma-Hydroxy-alpha-diazo-beta-ketoesters are key intermediates in the chemistry of penicilin-based antibiotics and natural products. The method developed here for the synthesis of ethyl 2-diazo-4-hydroxy-3-oxo-butanoate 17 (in two steps from the diazo mercurial 2) compares very favorably with those reported in the literature for similar compounds. The Rh2(OAc)4-mediated intramolecular OH-insertion reaction of the diazo hydroxy ester 17 was investigated, furnishing the oxetan-3-one-2-carboxil...

  10. Degradation characteristic of monoazo, diazo and anthraquinone dye by UV/H{sub 2}O{sub 2} process

    Energy Technology Data Exchange (ETDEWEB)

    Abidin, Che Zulzikrami Azner, E-mail: zulzikrami@unimap.edu.my, E-mail: drfahmi@unimap.edu.my, E-mail: umifazara@unimap.edu.my, E-mail: fatinnadhirah89@gmail.com; Fahmi, Muhammad Ridwan, E-mail: zulzikrami@unimap.edu.my, E-mail: drfahmi@unimap.edu.my, E-mail: umifazara@unimap.edu.my, E-mail: fatinnadhirah89@gmail.com; Fazara, Md Ali Umi, E-mail: zulzikrami@unimap.edu.my, E-mail: drfahmi@unimap.edu.my, E-mail: umifazara@unimap.edu.my, E-mail: fatinnadhirah89@gmail.com; Nadhirah, Siti Nurfatin, E-mail: zulzikrami@unimap.edu.my, E-mail: drfahmi@unimap.edu.my, E-mail: umifazara@unimap.edu.my, E-mail: fatinnadhirah89@gmail.com [School of Environmental Engineering, University Malaysia Perlis (UniMAP), Kompleks Pusat Pengajian Jejawi 3, 02600 Arau, Perlis (Malaysia)

    2014-10-24

    In this study, the degradation characteristic of monoazo, diazo and anthraquinone dye by UV/H{sub 2}O{sub 2} process was evaluated based on the trend of color, chemical oxygen demand (COD) and total organic carbon (TOC) removal. Three types of dyes consist of monoazo, diazo and anthraquinone dyes were used to compare the degradation mechanism of the dyes. The UV/H{sub 2}O{sub 2} experiments were conducted in a laboratory scale cylindrical glass reactor operated in semi-batch mode. The UV/Vis characterization of monoazo, diazo and anthraquinone dye indicated that the rapid degradation of the dyes by UV/H{sub 2}O{sub 2} process is meaningful with respect to decolourization, as a result of the azo bonds and substitute antraquinone chromophore degradation. However, this process is not efficient for aromatic amines removal. The monoazo MO was difficult to be decolorized than diazo RR120 dye, which imply that number of sulphonic groups in the dye molecules determines the reactivity with hydroxyl radical. The increased in COD removal is the evidence for oxidation and decreased in carbon content of dye molecules. TOC removal analysis shows that low TOC removal of monoazo MO and diazo RR120, as compared to anthraquinone RB19 may indicate an accumulation of by-products that are resistant to the H{sub 2}O{sub 2} photolysis.

  11. A Versatile Route to Unstable Diazo Compounds via Oxadiazolines and their Use in Aryl-Alkyl Cross-Coupling Reactions.

    Science.gov (United States)

    Greb, Andreas; Poh, Jian-Siang; Greed, Stephanie; Battilocchio, Claudio; Pasau, Patrick; Blakemore, David C; Ley, Steven V

    2017-12-22

    Coupling of readily available boronic acids and diazo compounds has emerged recently as a powerful metal-free carbon-carbon bond forming method. However, the difficulty in forming the unstable diazo compound partner in a mild fashion has hitherto limited their general use and the scope of the transformation. Here, we report the application of oxadiazolines as precursors for the generation of an unstable family of diazo compounds using flow UV photolysis and their first use in divergent protodeboronative and oxidative C(sp 2 )-C(sp 3 ) cross-coupling processes, with excellent functional-group tolerance. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. A reagent for safe and efficient diazo-transfer to primary amines: 2-azido-1,3-dimethylimidazolinium hexafluorophosphate.

    Science.gov (United States)

    Kitamura, Mitsuru; Kato, So; Yano, Masakazu; Tashiro, Norifumi; Shiratake, Yuichiro; Sando, Mitsuyoshi; Okauchi, Tatsuo

    2014-07-07

    Organic azides were prepared from primary amines in high yields by a metal free diazo-transfer reaction using 2-azido-1,3-dimethylimidazolinium hexafluorophosphate (ADMP), which is safe and stable crystalline. The choice of base was important in the diazo-transfer reaction. In general, 4-(N,N-dimethyl)aminopyridine (DMAP) was efficient, but a stronger base such as alkylamine or DBU was more appropriate for the reaction of nucleophilic primary amines. X-ray single crystal structural analysis and geometry optimization using density functional theory (B3LYP/6-31G**) were conducted to study the ADMP structure, and the diazo-transfer reaction mechanism was explained with the help of the results of these analyses.

  13. Comparison of the vanadate oxidase method with the diazo method for serum bilirubin determination in dog, monkey, and rat.

    Science.gov (United States)

    Ameri, Mehrdad; Schnaars, Henry; Sibley, John; Honor, David

    2011-01-01

    The most widely used method for bilirubin concentration determination is the diazo method, which measures the color of azobilirubin. The vanadate oxidase method is based on oxidation of bilirubin to biliverdin by vanadate. The objective of this study was to compare total and direct bilirubin concentration ([Bt] and [Bd], respectively) determined by the diazo and vanadate oxidase methods in pooled serum samples from dogs, monkeys, and rats spiked with panels of different concentrations of bilirubin standards. Pooled serum samples from 40 dogs, 40 monkeys, and 60 rats were spiked with either ditaurine conjugates of bilirubin or a standard reference material. The results obtained from both assays were compared using Deming regression analysis. The intra- and interassay precision, expressed as a percentage of the coefficient of variation (%CV), was determined for [Bt] and [Bd], and the mean percentage of recovery was calculated. The vanadate oxidase method displayed an excellent correlation (r  =  0.99-1.00) with the diazo method. Using Deming regression, there were minimal negative or positive constant and proportional biases for [Bt] and [Bd]. The precision studies revealed that the vanadate oxidase method has comparable between-run and within-run CVs to those of the diazo method. The recovery study demonstrated that the diazo method more closely approximates the expected values of [Bt]. In conclusion, the vanadate oxidase method is a simple and rapid method that can be employed as an alternative to the diazo method when interfering substances are present in the serum samples of dog, monkey, and rat.

  14. Gold(I)-catalyzed diazo cross-coupling: a selective and ligand-controlled denitrogenation/cyclization cascade.

    Science.gov (United States)

    Xu, Guangyang; Zhu, Chenghao; Gu, Weijin; Li, Jian; Sun, Jiangtao

    2015-01-12

    An unprecedented gold-catalyzed ligand-controlled cross-coupling of diazo compounds by sequential selective denitrogenation and cyclization affords N-substituted pyrazoles in a position-switchable mode. This novel transformation features selective decomposition of one diazo moiety and simultaneous preservation of the other one from two substrates. Notably, the choice of the ancillary ligand to the gold complex plays a pivotal role on the chemo- and regioselectivity of the reactions. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Rapid and sensitive detection of clenbuterol using a fluorescence nanosensor based on diazo coupling mechanism

    Science.gov (United States)

    Thanh Hop Tran, Thi; Huong Do, Thi Mai; Hoang, Mai Ha; Tuyen Nguyen, Duc; Le, Quang Tuan; Nghia Nguyen, Duc; Ngo, Trinh Tung

    2015-01-01

    In this paper, the fluorescence resonance energy transfer (FRET) effect has been used for fabrication of nanosensor for the detection of clenbuterol. In the nanosensor, the CdTe quantum dots (QDs) are the donors while the acceptor is the super-macromolecule formed by the diazoation coupling mechanism between diazo clenbuterol and naphthylethylene diamine. Changes in fluorescence intensities of nanosensor were used to determine the clenbuterol concentration. We have successfully fabricated a nanosensor for detection of clenbuterol sensible to clenbuterol concentration of 10-12 g ml-1.

  16. Trifluoromethylthiolation and Trifluoromethylselenolation of α-Diazo Esters Catalyzed by Copper.

    Science.gov (United States)

    Matheis, Christian; Krause, Thilo; Bragoni, Valentina; Goossen, Lukas J

    2016-08-22

    α-Diazo esters are smoothly converted into the corresponding trifluoromethyl thio- or selenoethers by reaction with Me4 NSCF3 or Me4 NSeCF3 , respectively, in the presence of catalytic amounts of copper thiocyanate. This straightforward method gives high yields under neutral conditions at room temperature and is applicable to a wide range of functionalized molecules, including diverse α-amino acid derivatives. It is well-suited for the late-stage introduction of trifluoromethylthio or -seleno groups into drug-like molecules. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Adsorption of the diazo dye Direct Red 23 onto a zinc oxide surface: A spectroscopic study

    Science.gov (United States)

    Lucilha, Adriana Campano; Bonancêa, Carlos Eduardo; Barreto, Wagner José; Takashima, Keiko

    2010-01-01

    The adsorption of the diazo dye Direct Red 23 onto a zinc oxide surface at 30 °C in the dark was investigated. The color reduction was monitored by spectrophotometry at 503 nm. The FTIR and Raman spectra of the Direct Red 23 adsorption as a function of ZnO concentration were registered. From the PM3 semi-empirical calculations of the atomic charge density and dipole moment of the Direct Red 23 molecule, it was demonstrated that the azo dye molecule may be adsorbed onto the ZnO surface through molecule geometry modifications, enhancing the interfacial area causing a variation in the bonding frequencies.

  18. Phase I study of 6-diazo-5-oxo-L-norleucine (DON).

    Science.gov (United States)

    Sklaroff, R B; Casper, E S; Magill, G B; Young, C W

    1980-01-01

    We conducted a phase I study of 6-diazo-5-oxo-L-norleucine given iv on a twice weekly schedule. Twenty-six evaluable patients received 31 courses of the drug. Doses ranged from 100 to 500 mg/m2. Nausea with vomiting was the dose-limiting toxic effect, transient thrombocytopenia was seen frequently, and mucositis occurred in 39% of the patients. No definite therapeutic responses were observed in 18 patients with measurable lesions. The recommended dose for phase II studies is 200-300 mg/m2 iv twice weekly.

  19. A chiral Brønsted acid-catalyzed highly enantioselective Mannich-type reaction of α-diazo esters with in situ generated N-acyl ketimines.

    Science.gov (United States)

    Unhale, Rajshekhar A; Sadhu, Milon M; Ray, Sumit K; Biswas, Rayhan G; Singh, Vinod K

    2018-04-03

    A chiral phosphoric acid-catalyzed asymmetric Mannich-type reaction of α-diazo esters with in situ generated N-acyl ketimines, derived from 3-hydroxyisoindolinones has been demonstrated in this communication. A variety of isoindolinone-based α-amino diazo esters bearing a quaternary stereogenic center were afforded in high yields (up to 99%) with excellent enantioselectivities (up to 99% ee). Furthermore, the synthetic utility of the products has been depicted by the hydrogenation of the diazo moiety of adducts.

  20. λ5-Phosphorus-Containing α-Diazo Compounds: A Valuable Tool for Accessing Phosphorus-Functionalized Molecules.

    Science.gov (United States)

    Marinozzi, Maura; Pertusati, Fabrizio; Serpi, Michaela

    2016-11-23

    The compounds characterized by the presence of a λ 5 -phosphorus functionality at the α-position with respect to the diazo moiety, here referred to as λ 5 -phosphorus-containing α-diazo compounds (PCDCs), represent a vast class of extremely versatile reagents in organic chemistry and are particularly useful in the preparation of phosphonate- and phosphinoxide-functionalized molecules. Indeed, thanks to the high reactivity of the diazo moiety, PCDCs can be induced to undergo a wide variety of chemical transformations. Among them are carbon-hydrogen, as well as heteroatom-hydrogen insertion reactions, cyclopropanation, ylide formation, Wolff rearrangement, and cycloaddition reactions. PCDCs can be easily prepared from readily accessible precursors by a variety of different methods, such as diazotization, Bamford-Stevens-type elimination, and diazo transfer reactions. This evidence along with their relative stability and manageability make them appealing tools in organic synthesis. This Review aims to demonstrate the ongoing utility of PCDCs in the modern preparation of different classes of phosphorus-containing compounds, phosphonates, in particular. Furthermore, to address the lack of precedent collective papers, this Review also summarizes the methods for PCDCs preparation.

  1. Fe(HSO{sub 4}){sub 3} as an Efficient Catalyst for Diazotization and Diazo Coupling Reactions

    Energy Technology Data Exchange (ETDEWEB)

    Rahimizadeh, Mohammad; Eshghi, Hossein; Shiri, Ali; Ghadamyari, Zohreh; Matin, Maryam M.; Pordeli, Parvaneh [Ferdowsi Univ. of Mashhad, Mashhad (Iran, Islamic Republic of); Oroojalian, Fatemeh [Univ. of Tehran, Tehran (Iran, Islamic Republic of)

    2012-12-15

    Diazo coupling reactions of aromatic amines with 2-naphthol in a green, efficient and easy procedure is described. Ferric hydrogensulfate catalyses this reaction in water at room temperature and short reaction time with high yields. The antibacterial activities of the synthesized compounds against four pathogenic bacteria are also investigated.

  2. Design and synthesis of brain-targeted prodrugs of the glutamine antagonist 6-Diazo-5-oxo-L-norleucine

    Czech Academy of Sciences Publication Activity Database

    Tenora, Lukáš; Novotná, Kateřina; Monincová, Lenka; Jančařík, Andrej; Nedelcovych, M.; Alt, J.; Rais, R.; Slusher, B. S.; Majer, Pavel

    2017-01-01

    Roč. 284, Suppl 1 (2017), s. 344 ISSN 1742-464X. [FEBS Congress /42./ From Molecules to Cells and Back. 10.09.2017-14.09.2017, Jerusalem] Institutional support: RVO:61388963 Keywords : 6-Diazo-5-oxo-L-norleucine * prodrugs Subject RIV: CE - Biochemistry

  3. Design and synthesis of brain-targeted prodrugs of the glutamine antagonist 6-Diazo-5-oxo-L-norleucine

    Czech Academy of Sciences Publication Activity Database

    Tenora, Lukáš; Novotná, Kateřina; Monincová, Lenka; Jančařík, Andrej; Gadiano, A. J.; Dash, R.; Rais, R.; Alt, J.; Slusher, B. S.; Majer, Pavel

    2017-01-01

    Roč. 284, Suppl 1 (2017), s. 345 ISSN 1742-464X. [FEBS Congress /42./ From Molecules to Cells and Back. 10.09.2017-14.09.2017, Jerusalem] Institutional support: RVO:61388963 Keywords : 6-Diazo-5-oxo-L-norleucine * prodrugs Subject RIV: CE - Biochemistry

  4. 1,7-Cyclization of 1-diazo-2,4-pentadiene and its heteroanalogues: DFT study

    Science.gov (United States)

    Subbotina, Julia O.; Bakulev, V. A.; Herges, R.; Fabian, W. M. F.

    1,7-Dipolar cyclizations of 1-diazo-2,4-pentadiene 1a and its heteroanalogues 1b,c and 4c were studied using density functional theory (DFT). Although the heteroanalogue 1c has an appropriate electronic structure to allow for pseudopericyclic cyclization, natural bond order (NBO) analysis has provided evidence for the electrocyclic ring closure. Magnetic criteria (anisotropy of the induced current density [ACID], nucleus-independent chemical shifts [NICS]) confirmed the pericyclic character of the located transition states 2a,c and 5c. The activation barriers for the cyclization of 1-diazo-2,4-pentadiene 1a and its aza analogues 1c, 4c are 3.3, 8.2, and 12.3 kcal/mol at the B3LYP/6-31G(d) level, respectively. The higher barrier of the 1c?3c and 4c?3c reactions compared with 1a?3a is in line with the Hammond postulate. The out-of-plane distorted geometry of the cyclic product is an additional factor arguing against a pseudopericyclic mechanism.

  5. Chiral Nickel(II) Complex Catalyzed Enantioselective Doyle-Kirmse Reaction of α-Diazo Pyrazoleamides.

    Science.gov (United States)

    Lin, Xiaobin; Tang, Yu; Yang, Wei; Tan, Fei; Lin, Lili; Liu, Xiaohua; Feng, Xiaoming

    2018-03-07

    Although high enantioselectivity of [2,3]-sigmatropic rearrangement of sulfonium ylides (Doyle-Kirmse reaction) has proven surprisingly elusive using classic chiral Rh(II) and Cu(I) catalysts, in principle it is due to the difficulty in fine discrimination of the heterotopic lone pairs of sulfur and chirality inversion at sulfur of sulfonium ylides. Here, we show that the synergistic merger of new α-diazo pyrazoleamides and a chiral N, N'-dioxide-nickel(II) complex catalyst enables a highly enantioselective Doyle-Kirmse reaction. The pyrazoleamide substituent serves as both an activating and a directing group for the ready formation of a metal-carbene- and Lewis-acid-bonded ylide intermediate in the assistance of a dual-tasking nickel(II) complex. An alternative chiral Lewis-acid-bonded ylide pathway greatly improves the product enantiopurity even for the reaction of a symmetric diallylsulfane. The majority of transformations over a series of aryl- or vinyl-substituted α-diazo pyrazoleamindes and sulfides proceed rapidly (within 5-20 min in most cases) with excellent results (up to 99% yield and 96% ee), providing a breakthrough in enantioselective Doyle-Kirmse reaction.

  6. Fabrication and electrical characterization of Al/diazo compound containing polyoxy chain/p-Si device structure

    International Nuclear Information System (INIS)

    Birel, Ozgul; Kavasoglu, Nese; Kavasoglu, A. Sertap; Dincalp, Haluk; Metin, Bengul

    2013-01-01

    Diazo-compounds are important class of chemical compounds in terms of optical and electronic properties which make them potentially attractive for device applications. Diazo compound containing polyoxy chain has been deposited on p-Si. Current–voltage characteristics of Al/diazo compound containing polyoxy chain/p-Si structure present rectifying behaviour. The Schottky barrier height (SBH), diode factor (n), reverse saturation current (I o ), interface state density (N ss ) of Al/diazo compound containing polyoxy chain/p-Si structure have been calculated from experimental forward bias current–voltage data measured in the temperature range 100–320 K and capacitance–voltage data measured at room temperature and 1 MHz. The calculated values of SBH have ranged from 0.041 and 0.151 eV for the high and low temperature regions. Diode factor values fluctuate between the values 14 and 18 with temperature. Such a high diode factors stem from disordered interface layer in a junction structure as stated by Brötzmann et al. [M. Brötzmann, U. Vetter, H. Hofsäss, J. Appl. Phys. 106 (2009) 063704]. The calculated values of saturation current have ranged from 3×10 −11 A to 2.79×10 −7 A and interface state density have ranged from 5×10 11 eV −1 cm −2 and 4×10 13 eV −1 cm −2 as temperature increases. Results show that Al/diazo compound containing polyoxy chain/p-Si structure is a valuable candidate for device applications in terms of low reverse saturation current and low interface state density

  7. [Determination of serum acetaminophen based on the diazo reaction and its application in the evaluation of gastric emptying].

    Science.gov (United States)

    Li, Cai-na; Sun, Su-juan; Shen, Zhu-fang

    2015-05-01

    This study aims to establish a method to determine the serum acetaminophen concentration based on diazo reaction, and apply it in the gastric emptying evaluation. Theoretically, acetaminophen could take hydrolysis reaction in hydrochloric acid solution to produce p-aminophenol, which could then take diazo reaction resulting in a product with special absorption peak at 312 nm. Then the serum acetaminophen concentration and recovery rate were calculated according to the standard curve drawn with absorbance at 312 nm. ICR mice were given a dose of acetaminophen (500 mg x kg(-1)) by gavage and the serum acetaminophen was dynamically measured through the diazo reaction. Besides, ICR mice were subcutaneously injected with the long-acting GLP-1 analog GW002 before the gavage of acetaminophen, and serum acetaminophen concentration was measured as above to study how GW002 could influence the gastric emptying. The data showed acetaminophen ranging from 0 to 160 μg x mL(-1) could take diazo reaction with excellent linear relationship, and the regression equation was y = 0.0181 x +0.0104, R2 = 0.9997. The serum acetaminophen was also measured with good linear relationship (y = 0.0045 x + 0.0462, R = 0.9982) and the recovery rate was 97.4%-116.7%. The serum concentration of acetaminophen reached peak at about 0.5 h after gavage, and then gradually decreased. GW002 could significantly lower the serum acetaminophen concentration and make the area under the concentration-time curve (AUC) decrease by 28.4%. In conclusion, a method for the determination of serum acetaminophen based on the diazo reaction was established with good accuracy and could be used in the evaluation of gastric emptying.

  8. Fabrication and electrical characterization of Al/diazo compound containing polyoxy chain/p-Si device structure

    Energy Technology Data Exchange (ETDEWEB)

    Birel, Ozgul [Mugla Sitki Kocman University, Faculty of Science, Chemistry Department, 48000-Muğla (Turkey); Kavasoglu, Nese, E-mail: knesese@gmail.com [Mugla Sitki Kocman University, Faculty of Science, Physics Department, Photovoltaic Material and Device Laboratory, 48000-Muğla (Turkey); Kavasoglu, A. Sertap [Mugla Sitki Kocman University, Faculty of Science, Physics Department, Photovoltaic Material and Device Laboratory, 48000-Muğla (Turkey); Dincalp, Haluk [Celal Bayar University, Faculty of Arts and Science, Chemistry Department, 45000-Manisa (Turkey); Metin, Bengul [Mugla Sitki Kocman University, Faculty of Science, Physics Department, Photovoltaic Material and Device Laboratory, 48000-Muğla (Turkey)

    2013-03-01

    Diazo-compounds are important class of chemical compounds in terms of optical and electronic properties which make them potentially attractive for device applications. Diazo compound containing polyoxy chain has been deposited on p-Si. Current–voltage characteristics of Al/diazo compound containing polyoxy chain/p-Si structure present rectifying behaviour. The Schottky barrier height (SBH), diode factor (n), reverse saturation current (I{sub o}), interface state density (N{sub ss}) of Al/diazo compound containing polyoxy chain/p-Si structure have been calculated from experimental forward bias current–voltage data measured in the temperature range 100–320 K and capacitance–voltage data measured at room temperature and 1 MHz. The calculated values of SBH have ranged from 0.041 and 0.151 eV for the high and low temperature regions. Diode factor values fluctuate between the values 14 and 18 with temperature. Such a high diode factors stem from disordered interface layer in a junction structure as stated by Brötzmann et al. [M. Brötzmann, U. Vetter, H. Hofsäss, J. Appl. Phys. 106 (2009) 063704]. The calculated values of saturation current have ranged from 3×10{sup −11} A to 2.79×10{sup −7} A and interface state density have ranged from 5×10{sup 11} eV{sup −1} cm{sup −2} and 4×10{sup 13} eV{sup −1} cm{sup −2} as temperature increases. Results show that Al/diazo compound containing polyoxy chain/p-Si structure is a valuable candidate for device applications in terms of low reverse saturation current and low interface state density.

  9. Fabrication and electrical characterization of Al/diazo compound containing polyoxy chain/p-Si device structure

    Science.gov (United States)

    Birel, Ozgul; Kavasoglu, Nese; Kavasoglu, A. Sertap; Dincalp, Haluk; Metin, Bengul

    2013-03-01

    Diazo-compounds are important class of chemical compounds in terms of optical and electronic properties which make them potentially attractive for device applications. Diazo compound containing polyoxy chain has been deposited on p-Si. Current-voltage characteristics of Al/diazo compound containing polyoxy chain/p-Si structure present rectifying behaviour. The Schottky barrier height (SBH), diode factor (n), reverse saturation current (Io), interface state density (Nss) of Al/diazo compound containing polyoxy chain/p-Si structure have been calculated from experimental forward bias current-voltage data measured in the temperature range 100-320 K and capacitance-voltage data measured at room temperature and 1 MHz. The calculated values of SBH have ranged from 0.041 and 0.151 eV for the high and low temperature regions. Diode factor values fluctuate between the values 14 and 18 with temperature. Such a high diode factors stem from disordered interface layer in a junction structure as stated by Brötzmann et al. [M. Brötzmann, U. Vetter, H. Hofsäss, J. Appl. Phys. 106 (2009) 063704]. The calculated values of saturation current have ranged from 3×10-11 A to 2.79×10-7 A and interface state density have ranged from 5×1011 eV-1 cm-2 and 4×1013 eV-1 cm-2 as temperature increases. Results show that Al/diazo compound containing polyoxy chain/p-Si structure is a valuable candidate for device applications in terms of low reverse saturation current and low interface state density.

  10. Synthesis of Donor/Acceptor-Substituted Diazo Compounds in Flow and Their Application in Enantioselective Dirhodium-Catalyzed Cyclopropanation and C-H Functionalization.

    Science.gov (United States)

    Rackl, Daniel; Yoo, Chun-Jae; Jones, Christopher W; Davies, Huw M L

    2017-06-16

    A tandem reaction system has been developed for the preparation of donor/acceptor-substituted diazo compounds in continuous flow coupled to dirhodium-catalyzed C-H functionalization or cyclopropanation. Hydrazones were oxidized in flow by solid-supported N-iodo-p-toluenesulfonamide potassium salt (PS-SO 2 NIK) to generate the diazo compounds, which were then purified by passing through a column of molecular sieves/sodium thiosulfate.

  11. Synthesis of Imidazopyridines via Copper-Catalyzed, Formal Aza-[3 + 2] Cycloaddition Reaction of Pyridine Derivatives with α-Diazo Oxime Ethers.

    Science.gov (United States)

    Park, Sangjune; Kim, Hyunseok; Son, Jeong-Yu; Um, Kyusik; Lee, Sooho; Baek, Yonghyeon; Seo, Boram; Lee, Phil Ho

    2017-10-06

    The Cu-catalyzed, formal aza-[3 + 2] cycloaddition reaction of pyridine derivatives with α-diazo oxime ethers in trifluoroethanol was used to synthesize imidazopyridines via the release of molecular nitrogen and elimination of alcohol. These methods enabled modular synthesis of a wide range of N-heterobicyclic compounds such as imidazopyridazines, imidazopyrimidines, and imidazopyrazines with an α-imino Cu-carbenoid generated from the α-diazo oxime ethers and copper.

  12. Synthesis of spiro-4H-pyrazole-oxindoles and fused 1H-pyrazoles via divergent, thermally induced tandem cyclization/migration of alkyne-tethered diazo compounds.

    Science.gov (United States)

    Zhang, Cheng; Dong, Shanliang; Zheng, Yang; He, Ciwang; Chen, Jiaolong; Zhen, Jingsen; Qiu, Lihua; Xu, Xinfang

    2018-01-31

    A thermally induced, substrate-dependent reaction of alkynyl diazo compounds has been developed. This transformation produces spiro-4H-pyrazole-oxindoles and fused 1H-pyrazoles in good to high yields from the corresponding alpha-cyano and alpha-sulfonyl diazo compounds. The salient features of this reaction include excellent chemoselectivity and atom-economy, mild reaction conditions, simple purification and potential for large scale production.

  13. Covalently attached multilayer assemblies of diazo-resins and binuclear cobalt phthalocyanines

    International Nuclear Information System (INIS)

    Li Xiaofang; Zhao Shuang; Yang Min; Sun Changqing; Guo, Liping

    2005-01-01

    By using the ionic self-assembly technique, ordered multilayer thin films composed of diazo-resin (DAR) as polycation and water-soluble binuclear cobalt phthalocyaninehexasulfonate (Bi-CoPc) as polyanion were alternately fabricated on quartz, CaF 2 and glassy carbon electrodes (GCEs). Upon ultraviolet irradiation, the adjacent interface of the multilayer films reacted to form a covalently cross-linking structure. The obtained thin films were characterized by ultraviolet (UV)-vis, Fourier transform infrared spectrometer (FTIR), X-ray diffraction (XRD), atomic force microscope (AFM), surface photovoltage spectra (SPS), and cyclic voltammetry. The results show that the uniform, highly stable and ordered multilayer thin films were formed. The linkage nature between the adjacent interface of the multilayer films converts from ionic to covalent, and, as a result, the stability of the multilayer thin films dramatically improved. The multilayer thin films on GCEs also exhibited excellent electrochemical behavior

  14. Covalently attached multilayer assemblies of diazo-resins and binuclear cobalt phthalocyanines

    Energy Technology Data Exchange (ETDEWEB)

    Li Xiaofang [Key Lab of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130023 (China); Zhao Shuang [Key Lab of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130023 (China); Yang Min [Key Lab of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130023 (China); Sun Changqing [Key Lab of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130023 (China)]. E-mail: sunchq@mail.jlu.edu.cn; Guo, Liping [Department of Chemistry, Northeast Normal University, Changchun 130024 (China)

    2005-05-01

    By using the ionic self-assembly technique, ordered multilayer thin films composed of diazo-resin (DAR) as polycation and water-soluble binuclear cobalt phthalocyaninehexasulfonate (Bi-CoPc) as polyanion were alternately fabricated on quartz, CaF{sub 2} and glassy carbon electrodes (GCEs). Upon ultraviolet irradiation, the adjacent interface of the multilayer films reacted to form a covalently cross-linking structure. The obtained thin films were characterized by ultraviolet (UV)-vis, Fourier transform infrared spectrometer (FTIR), X-ray diffraction (XRD), atomic force microscope (AFM), surface photovoltage spectra (SPS), and cyclic voltammetry. The results show that the uniform, highly stable and ordered multilayer thin films were formed. The linkage nature between the adjacent interface of the multilayer films converts from ionic to covalent, and, as a result, the stability of the multilayer thin films dramatically improved. The multilayer thin films on GCEs also exhibited excellent electrochemical behavior.

  15. The radiation-induced degradation of a diazo dye in aqueous solution Pt. 2

    International Nuclear Information System (INIS)

    El-Assy, N.B.; Abdel-Rehim, F.; Abdel-Gawad, A.S.; Abdel-Fattah, A.A.

    1992-01-01

    The effect of γ-radiation on the color intensity of aerated, deaerated and oxygenated aqueous solutions of a diazo dye (Helion Red 8B) has been investigated. The decoloration yields of Helion Red 8B neutral aqueous solution, G(-Dye), for the nitrogen-, oxygen- and aerated-saturated solutions were found to be 0.77, 0.46 and 0.36 in the respective early stage. The rate constant for the reaction of the OH radical with the HR8B dye, obtained from competition kinetics using ethanol, was found to be 1.3*10 10 M -1 *s -1 . In aerated solutions (pH 3), the G(-Dye) decreased markedly upon the addition of a very small amount of ethanol. Suggestions are made for possible use of the dye as a radiation dosimeter in the dose range of 0.1 to 2 kGy. (author) 16 refs.; 8 figs.; 1 tab

  16. Gold-Catalyzed Formal [4+1]/[4+3] Cycloadditions of Diazo Esters with Triazines.

    Science.gov (United States)

    Zhu, Chenghao; Xu, Guangyang; Sun, Jiangtao

    2016-09-19

    Reported herein is the unprecedented gold-catalyzed formal [4+1]/[4+3] cycloadditions of diazo esters with hexahydro-1,3,4-triazines, thus providing five- and seven-membered heterocycles in moderate to high yields under mild reaction conditions. These reactions feature the use of a gold complex to accomplish the diverse annulations and the first example of the involvement of a gold metallo-enolcarbene in a cycloaddition. It is also the first utilization of stable triazines as formal dipolar adducts in the carbene-involved cycloadditions. Mechanistic investigations reveal that the triazines reacted directly, rather than as formaldimine precursors, in the reaction process. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Theoretical Study on Vibrational Spectra, Detonation Properties and Pyrolysis Mechanism for Cyclic 2-Diazo-4,6-dinitrophenol

    Science.gov (United States)

    Li, Xiao-hong; Yin, Geng-xin; Zhang, Xian-zhou

    2012-10-01

    Based on the full optimized molecular geometrical structures at the DFT-B3LYP/6-311+G** level, there exists intramolecular hydrogen bond interaction for cyclic 2-diazo-4,6-dinitrophenol. The assigned infrared spectrum is obtained and used to compute the thermodynamic properties. The results show that there are four main characteristic regions in the calculated IR spectra of the title compound. The detonation velocities and pressures are also evaluated by using Kamlet-Jacobs equations based on the calculated density and condensed phase heat of formation. Thermal stability and the pyrolysis mechanism of 2-diazo-4,6-dinitrophenol are investigated by calculating the bond dissociation energies at the B3LYP/6-311+G** level.

  18. Highly Stereoselective Gold-Catalyzed Coupling of Diazo Reagents and Fluorinated Enol Silyl Ethers to Tetrasubstituted Alkenes.

    Science.gov (United States)

    Liao, Fu-Min; Cao, Zhong-Yan; Yu, Jin-Sheng; Zhou, Jian

    2017-02-20

    We report a highly stereoselective synthesis of all-carbon or fluorinated tetrasubstituted alkenes from diazo reagents and fluorinated enol silyl ethers, using C-F bond as a synthetic handle. Cationic Au I catalysis plays a key role in this reaction. Remarkable fluorine effects on the reactivity and selectivity was also observed. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. A Versatile Room-Temperature Route to Di- and Trisubstituted Allenes Using Flow-Generated Diazo Compounds.

    Science.gov (United States)

    Poh, Jian-Siang; Tran, Duc N; Battilocchio, Claudio; Hawkins, Joel M; Ley, Steven V

    2015-06-26

    A copper-catalyzed coupling reaction between flow-generated unstabilized diazo compounds and terminal alkynes provides di- and trisubstituted allenes. This extremely mild and rapid transformation is highly tolerant of several functional groups. © 2015 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

  20. Rapid Asymmetric Synthesis of Disubstituted Allenes by Coupling of Flow-Generated Diazo Compounds and Propargylated Amines.

    Science.gov (United States)

    Poh, Jian-Siang; Makai, Szabolcs; von Keutz, Timo; Tran, Duc N; Battilocchio, Claudio; Pasau, Patrick; Ley, Steven V

    2017-02-06

    We report herein the asymmetric coupling of flow-generated unstabilized diazo compounds and propargylated amine derivatives, using a new pyridinebis(imidazoline) ligand, a copper catalyst and base. The reaction proceeds rapidly, generating chiral allenes in 10-20 minutes with high enantioselectivity (89-98 % de/ee), moderate yields and a wide functional group tolerance. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Flow chemistry as a discovery tool to access sp2-sp3 cross-coupling reactions via diazo compounds.

    Science.gov (United States)

    Tran, Duc N; Battilocchio, Claudio; Lou, Shing-Bong; Hawkins, Joel M; Ley, Steven V

    2015-02-01

    The work takes advantage of an important feature of flow chemistry, whereby the generation of a transient species (or reactive intermediate) can be followed by a transfer step into another chemical environment, before the intermediate is reacted with a coupling partner. This concept is successfully applied to achieve a room temperature sp 2 -sp 3 cross coupling of boronic acids with diazo compounds, these latter species being generated from hydrazones under flow conditions using MnO 2 as the oxidant.

  2. gem-Difluoroolefination of Diazo Compounds with TMSCF3 or TMSCF2Br: Transition-Metal-Free Cross-Coupling of Two Carbene Precursors.

    Science.gov (United States)

    Hu, Mingyou; Ni, Chuanfa; Li, Lingchun; Han, Yongxin; Hu, Jinbo

    2015-11-18

    A new olefination protocol for transition-metal-free cross-coupling of two carbene fragments arising from two different sources, namely, a nonfluorinated carbene fragment resulting from a diazo compound and a difluorocarbene fragment derived from Ruppert-Prakash reagent (TMSCF3) or TMSCF2Br, has been developed. This gem-difluoroolefination proceeds through the direct nucleophilic addition of diazo compounds to difluorocarbene followed by elimination of N2. Compared to previously reported Cu-catalyzed gem-difluoroolefination of diazo compounds with TMSCF3, which possesses a narrow substrate scope due to a demanding requirement on the reactivity of diazo compounds and in-situ-generated CuCF3, this transition-metal-free protocol affords a general and efficient approach to various disubstituted 1,1-difluoroalkenes, including difluoroacrylates, diaryldifluoroolefins, as well as arylalkyldifluoroolefins. In view of the ready availability of diazo compounds and difluorocarbene reagents and versatile transformations of 1,1-difluoroalkenes, this new gem-difluoroolefination method is expected to find wide applications in organic synthesis.

  3. Diazo compounds and N-tosylhydrazones: novel cross-coupling partners in transition-metal-catalyzed reactions.

    Science.gov (United States)

    Xiao, Qing; Zhang, Yan; Wang, Jianbo

    2013-02-19

    Transition-metal-catalyzed carbene transformations and cross-couplings represent two major reaction types in organometallic chemistry and organic synthesis. However, for a long period of time, these two important areas have evolved separately, with essentially no overlap or integration. Thus, an intriguing question has emerged: can cross-coupling and metal carbene transformations be merged into a single reaction cycle? Such a combination could facilitate the development of novel carbon-carbon bond-forming methodologies. Although this concept was first explored about 10 years ago, rapid developments inthis area have been achieved recently. Palladium catalysts can be used to couple diazo compounds with a wide variety of organic halides. Under oxidative coupling conditions, diazo compounds can also react with arylboronic acids and terminal alkynes. Both of these coupling reactions form carbon-carbon double bonds. As the key step in these catalytic processes, Pd carbene migratory insertion plays a vital role in merging the elementary steps of Pd intermediates, leading to novel carbon-carbon bond formations. Because the diazo substrates can be generated in situ from N-tosylhydrazones in the presence of base, the N-tosylhydrazones can be used as reaction partners, making this type of cross-coupling reaction practical in organic synthesis. N-Tosylhydrazones are easily derived from the corresponding aldehydes or ketones. The Pd-catalyzed cross-coupling of N-tosylhydrazones is considered a complementary reaction to the classic Shapiro reaction for converting carbonyl functionalities into carbon-carbon double bonds. It can also serve as an alternative approach for the Pd-catalyzed cross-coupling of carbonyl compounds, which is usually achieved via triflates. The combination of carbene formation and cross-coupling in a single catalytic cycle is not limited to Pd-catalyzed reactions. Recent studies of Cu-, Rh-, Ni-, and Co-catalyzed cross-coupling reactions with diazo

  4. Formation of nitrogen complexes when [Ru(NH3)5H2O]2+ ion reaction with diazo-acetic ester and aromatic salts of diazonium

    International Nuclear Information System (INIS)

    Shur, V.B.; Tikhonova, I.A.; Vol'pin, M.E.

    1978-01-01

    A possibility of formation of nitrogen complexes during transition metal compound interaction with aliphatic and aromatic diazo compounds is studied. It is shown that at the interaction of [Ru(NH 3 ) 5 H 2 O] 2+ with diazo-acetic ester in water (pH7) at 20 deg, quick splitting of the CN-bond in the ester molecule takes place with the formation of [Ru(NH 3 ) 5 N 2 ] 2+ and [(NH 3 ) 5 RuN 2 Ru(NH 3 ) 5 ] 4+ (NRRN) nitrogen complexes. The sum yield of complexes comprises 86% taking into acount diazo-acetic ester. Aromatic salts of diazonium, n-O 3 SC 6 H 4 N 2 and p-quinone diazide react with the [Ru(NH 3 ) 5 H 2 O] 2+ excess forming NRRN (the yield equals 40-53%). The reaction mechanism is discussed

  5. Catalyst-Dependent Chemoselective Formal Insertion of Diazo Compounds into C-C or C-H Bonds of 1,3-Dicarbonyl Compounds.

    Science.gov (United States)

    Liu, Zhaohong; Sivaguru, Paramasivam; Zanoni, Giuseppe; Anderson, Edward A; Bi, Xihe

    2018-05-08

    A catalyst-dependent chemoselective one-carbon insertion of diazo compounds into the C-C or C-H bonds of 1,3-dicarbonyl species is reported. In the presence of silver(I) triflate, diazo insertion into the C(=O)-C bond of the 1,3-dicarbonyl substrate leads to a 1,4-dicarbonyl product containing an all-carbon α-quaternary center. This reaction constitutes the first example of an insertion of diazo-derived carbenoids into acyclic C-C bonds. When instead scandium(III) triflate was applied as the catalyst, the reaction pathway switched to formal C-H insertion, affording 2-alkylated 1,3-dicarbonyl products. Different reaction pathways are proposed to account for this powerful catalyst-dependent chemoselectivity. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. The Wolff rearrangement of cyclic 2-diazo-1,3-diketones in electron impact - mass spectrometry - controlling the molecular fragmentation by means of low-energy electrons 18 to 70 eV

    International Nuclear Information System (INIS)

    Kuruc, J.; Kardosova, E.; Nikolaev, V. A.

    2016-01-01

    The electron-impact-induced fragmentations (the mass spectra, 17 - 70 eV) of cyclic 2-diazo-1,3-diketones were studied. As the suitable compounds were selected the following cyclic 2-diazo-1,3-diketones: 2-diazo-1,3-cyclohexanedione, Ia; 2-diazo-4,4-dimethyl-1,3-cyclohexanedione, Ib; 2-diazo-5,5-dimethyl-1,3-cyclohexanedione, Ic; 2-diazo-4,6-dioxa-5,5-dimethyl-1,3-cyclohexanedione, Id; and 2-diazo-5-phenyl-1,3-cyclohexanedione, Ie). The mass spectra were measured with Varian MAT 111 instrument with direct introduction of samples, with a source temperature of 120 grad C, energy of ionising electrons was in the range (17 - 70) eV. The elimination of the diazo group is the typical reaction of the fragmentation of the cyclic diazo-1,3-diketones after ionization of molecules by electron impact. All our studied cyclic diazo-1,3-diketones have a molecular ion with a relative intensity from 0.7 to 86.4%. Typical ions are [M]"+·, [M-N"_2]"+"·, [M-N_2-CO]"+"·, [M-N_2-CO-CH_2]"+"·, [M-N_2-CO-CH_3]"+"·. For all treatment cyclic diazo-1,3-diketones have been registered 3D mass spectra, for each cyclic diazo-1,3-diketone was proposed fragmentation scheme, including the general fragmentation scheme. The Wolff rearrangement is observed in all studied cyclic diazo-1,3-diketones after cleavage of nitrogen molecules. The energy of ionizing electrons ∼20 eV in the case of compounds Ib, Id - Ie dominating ions are fragments of the [M-N_2]"+"·, in the compound Ia at 18 and 20 eV is dominant fragment [M-N_2-CO-C_2H_2-H]"+"· and for the Ic at 30 eV becomes a dominant fragment [M-N_2-CH_3]"+"· (m/z = 123) but at (25 - 18) eV the most intensive ion is [M-N_2]"+"· (m/z = 138). (authors)

  7. A new reactivity mode for the diazo group: diastereoselective 1,3-aminoalkylation reaction of β-amino-α-diazoesters to give triazolines.

    Science.gov (United States)

    Kuznetsov, Alexey; Gulevich, Anton V; Wink, Donald J; Gevorgyan, Vladimir

    2014-08-18

    A novel mode of reactivity for the diazo group, the 1,3-addition of a nucleophile and an electrophile to the diazo group, has been realized in the intramolecular aminoalkylation of β-amino-α-diazoesters to form tetrasubstituted 1,2,3-triazolines. The reaction exhibited a broad scope, good functional group tolerance, and excellent diastereoselectivity. In addition, a new Au-catalyzed intramolecular transannulation reaction of the obtained propargyl triazolines to give pyrroles has been discovered. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Ruthenium(II)-Catalyzed C-H Activation of Imidamides and Divergent Couplings with Diazo Compounds: Substrate-Controlled Synthesis of Indoles and 3H-Indoles.

    Science.gov (United States)

    Li, Yunyun; Qi, Zisong; Wang, He; Yang, Xifa; Li, Xingwei

    2016-09-19

    Indoles are an important structural motif that is commonly found in biologically active molecules. In this work, conditions for divergent couplings between imidamides and acceptor-acceptor diazo compounds were developed that afforded NH indoles and 3H-indoles under ruthenium catalysis. The coupling of α-diazoketoesters afforded NH indoles by cleavage of the C(N2 )-C(acyl) bond whereas α-diazomalonates gave 3H-indoles by C-N bond cleavage. This reaction constitutes the first intermolecular coupling of diazo substrates with arenes by ruthenium-catalyzed C-H activation. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Direct Carboxylation of the Diazo Group ipso-C(sp2)-H bond with Carbon Dioxide: Access to Unsymmetrical Diazomalonates and Derivatives.

    Science.gov (United States)

    Liu, Qianyi; Li, Man; Xiong, Rui; Mo, Fanyang

    2017-12-15

    The direct carboxylation of the ipso-C(sp 2 )-H bond of a diazo compound with carbon dioxide under mild reaction conditions is described. This method is transition-metal-free, uses a weak base, and proceeds at ambient temperature under atmospheric pressure in carbon dioxide. The carboxylation exhibits high reactivity and is amenable to subsequent diversification. A series of unsymmetrical 1,3-diester/keto/amide diazo compounds are obtained with moderate to excellent yields (up to 99%) with good functional group compatibility.

  10. Straightforward Entry toward Highly Substituted 2,3-Dihydrobenz[ b]oxepines by Ring Expansion of Benzopyryliums with Donor-Acceptor Diazo Compounds.

    Science.gov (United States)

    Courant, Thibaut; Pasco, Morgane; Lecourt, Thomas

    2018-05-04

    Ylide-type reactivity of diazo compounds is exploited in a new way to prepare benzo[ b]oxepines thanks to the formation of three chemical bonds and two contiguous and highly substituted stereocenters in a single pot. This cationic reaction cascade first involves addition of a donor-acceptor-substituted diazo compound to a benzopyrylium. Selective 1,2 migration of the endocyclic C-C bond then results in a ring-expansion and generates a second oxocarbenium that is trapped by a nucleophile added sequentially.

  11. Masked rhodamine dyes of five principal colors revealed by photolysis of a 2-diazo-1-indanone caging group: synthesis, photophysics, and light microscopy applications.

    OpenAIRE

    Belov, V.; Mitronova, G.; Bossi, M.; Boyarski, V.; Hebisch, E.; Geisler, C.; Kolmakov, K.; Wurm, C.; Willig, K.; Hell, S.

    2014-01-01

    Caged rhodamine dyes (Rhodamines NN) of five basic colors were synthesized and used as “hidden” markers in subdiffractional and conventional light microscopy. These masked fluorophores with a 2-diazo-1-indanone group can be irreversibly photoactivated, either by irradiation with UV- or violet light (one-photon process), or by exposure to intense red light (λ∼750 nm; two-photon mode). All dyes possess a very small 2-diazoketone caging group incorporated into the 2-diazo-1-indanone residue with...

  12. Synthesis and characterization of spherical 2-diazo-4,6-dinitrophenol (DDNP)

    International Nuclear Information System (INIS)

    Yang Zongwei; Liu Yucun; Liu Dengcheng; Yan Liwei; Chen Ji

    2010-01-01

    Spherical 2-diazo-4,6-dinitrophenol (DDNP) with good flowability and controlled bulk density (0.65-0.95 g/cm 3 ) has been prepared at factory scale by the modified method using 4-methylphenol as crystal control ingredient. Results showed that the yield of product was increased by 5-10%, and the waste water was significantly decreased due to circulation use of waste water compared with traditional method. Synthesized spherical DDNP was characterized by IR, laser granularity measurement, SEM, HPLC and XRD. IR spectrum confirmed the structural features of spherical DDNP. The particle analysis revealed that the modified method could offer spherical DDNP with average particle size of 350 μm and high purity (>98.52%). The XRD peaks of spherical DDNP have similar diffraction angles as those of traditional DDNP. The DSC profile of spherical DDNP showed the exothermic decomposition in the temperature range of 161.2-188.5 deg. C. The product can be pressed at over 40 MPa without dead pressed phenomenon, and the minimum detonating charge of spherical DDNP was measured to be about 0.15 g. Furthermore, impact sensitivity test suggested that spherical DDNP is less sensitive than traditional DDNP.

  13. Comparison of Cu2+ and Zn2+ thermalcatalyst in treating diazo dye

    Science.gov (United States)

    Lau, Y. Y.; Wong, Y. S.; Ong, S. A.; Lutpi, N. A.; Ho, L. N.

    2018-05-01

    This research demonstrates the comparison between copper (II) sulphate (CuSO4) and zinc oxide (ZnO) as thermalcatalysts in thermolysis process for the treatment of diazo reactive black 5 (RB 5) wastewater. CuSO4 was found to be the most effective thermalcatalyst in comparison to ZnO. The color removal efficiency of RB 5 catalysed by CuSO4 and ZnO were 91.55 % at pH 9.5 and 7.36 % at pH 2, respectively. From the UV-Vis wavelength scan, CuSO4 catalyst is able to cleave the molecular structure bonding more efficiently compared to ZnO. ZnO which only show a slight decay on the main chemical network strands: azo bond, naphthalene and benzene rings whereas CuSO4 catalyst is able to fragment azo bond and naphthalene more effectively. The degradation reactions of CuSO4 and ZnO as thermalcatalysts in thermolysis process were compared.

  14. Kinetic and equilibrium study of adsorption of di-azo dyes on commercial activated carbon

    International Nuclear Information System (INIS)

    Hyali, E.A.S.A.; Abady, T.G.A.

    2013-01-01

    This research work is concerned with studying the adsorption of a number of di-azo dyes on commercial activated carbon (CAC). The synthesized dyes vary in their structures by the central parts. which are either ortho, meta or para phenvlene diamine. This variation affects the linearity of molecules, their spatial arrangement and electron movement throughout the molecule by resonance. Factors a fleeting adsorption process, such as the efiect of contact time, initial concentration, p1-I of the adsorption medium, adsorbent dose, effect of solvent and temperature were studied. The results indicated that, the adsorption process is fast in the first 10 mm, then gradually decreased with time and approaches maximum within 70-80 min for all the studied dyes. The increase of initial concentration and temperature decreased the adsorption efficiency. The results also shows that, the adsorption is found to be more efficient at low Ph value. The increase of the adsorbent dose increases the adsorption efficiency and decreases its capacity. The variation of solvent (ethanol-water ratio) indicates that the decrease of dielectric constant lowers the adsorption efficiency. The study included application of three adsorption isotherms, Freundlich, Langmuir and Tempkin on the experimental data of the studied systems. The results indicated that, Freundlich isotherm fits better the adsorption data. Kinetic analysis of the adsorption data was also conducted by employing 4 kinetic models; pseudo first order and pseudo second order, Elovich and intra particle diffusion equations. The results obtained conclude that, the studied systems follow the Pseudo second order model. (author)

  15. Microbial fuel cell operation using monoazo and diazo dyes as terminal electron acceptor for simultaneous decolourisation and bioelectricity generation

    International Nuclear Information System (INIS)

    Oon, Yoong-Sin; Ong, Soon-An; Ho, Li-Ngee; Wong, Yee-Shian; Oon, Yoong-Ling; Lehl, Harvinder Kaur; Thung, Wei-Eng; Nordin, Noradiba

    2017-01-01

    Highlights: • Monoazo and diazo dyes were used as electron acceptor in the abiotic cathode of MFC. • Simultaneous decolourisation and bioelectricity generation were achieved. • Azo dye structures influenced the decolourisation performance. • Positive relation between decolourisation rate and power performance. - Abstract: Monoazo and diazo dyes [New coccine (NC), Acid orange 7 (AO7), Reactive red 120 (RR120) and Reactive green 19 (RG19)] were employed as electron acceptors in the abiotic cathode of microbial fuel cell. The electrons and protons generated from microbial organic oxidation at the anode which were utilized for electrochemical azo dye reduction at the cathodic chamber was successfully demonstrated. When NC was employed as the electron acceptor, the chemical oxygen demand (COD) removal and dye decolourisation efficiencies obtained at the anodic and cathodic chamber were 73 ± 3% and 95.1 ± 1.1%, respectively. This study demonstrated that the decolourisation rates of monoazo dyes were ∼50% higher than diazo dyes. The maximum power density in relation to NC decolourisation was 20.64 mW/m"2, corresponding to current density of 120.24 mA/m"2. The decolourisation rate and power output of different azo dyes were in the order of NC > AO7 > RR120 > RG19. The findings revealed that the structure of dye influenced the decolourisation and power performance of MFC. Azo dye with electron-withdrawing group at para substituent to azo bond would draw electrons from azo bond; hence the azo dye became more electrophilic and more favourable for dye reduction.

  16. Microbial fuel cell operation using monoazo and diazo dyes as terminal electron acceptor for simultaneous decolourisation and bioelectricity generation

    Energy Technology Data Exchange (ETDEWEB)

    Oon, Yoong-Sin [Water Research Group (WAREG), School of Environmental Engineering, Universiti Malaysia Perlis, 02600, Arau, Perlis (Malaysia); Ong, Soon-An, E-mail: ongsoonan@yahoo.com [Water Research Group (WAREG), School of Environmental Engineering, Universiti Malaysia Perlis, 02600, Arau, Perlis (Malaysia); Ho, Li-Ngee [School of Materials Engineering, Universiti Malaysia Perlis, 02600, Arau, Perlis (Malaysia); Wong, Yee-Shian; Oon, Yoong-Ling; Lehl, Harvinder Kaur; Thung, Wei-Eng [Water Research Group (WAREG), School of Environmental Engineering, Universiti Malaysia Perlis, 02600, Arau, Perlis (Malaysia); Nordin, Noradiba [School of Materials Engineering, Universiti Malaysia Perlis, 02600, Arau, Perlis (Malaysia)

    2017-03-05

    Highlights: • Monoazo and diazo dyes were used as electron acceptor in the abiotic cathode of MFC. • Simultaneous decolourisation and bioelectricity generation were achieved. • Azo dye structures influenced the decolourisation performance. • Positive relation between decolourisation rate and power performance. - Abstract: Monoazo and diazo dyes [New coccine (NC), Acid orange 7 (AO7), Reactive red 120 (RR120) and Reactive green 19 (RG19)] were employed as electron acceptors in the abiotic cathode of microbial fuel cell. The electrons and protons generated from microbial organic oxidation at the anode which were utilized for electrochemical azo dye reduction at the cathodic chamber was successfully demonstrated. When NC was employed as the electron acceptor, the chemical oxygen demand (COD) removal and dye decolourisation efficiencies obtained at the anodic and cathodic chamber were 73 ± 3% and 95.1 ± 1.1%, respectively. This study demonstrated that the decolourisation rates of monoazo dyes were ∼50% higher than diazo dyes. The maximum power density in relation to NC decolourisation was 20.64 mW/m{sup 2}, corresponding to current density of 120.24 mA/m{sup 2}. The decolourisation rate and power output of different azo dyes were in the order of NC > AO7 > RR120 > RG19. The findings revealed that the structure of dye influenced the decolourisation and power performance of MFC. Azo dye with electron-withdrawing group at para substituent to azo bond would draw electrons from azo bond; hence the azo dye became more electrophilic and more favourable for dye reduction.

  17. Synthesis, characterisation and chemical reactivity of some new binuclear dioxouranium(VI) complexes derived from organic diazo compounds (Preprint No. CT-33)

    International Nuclear Information System (INIS)

    Pujar, M.A.; Pirgonde, B.R.

    1988-02-01

    A new series of binuclear dioxouranium(VI) complexes of polydentatate diazo compounds have been synthesised and characterised adequately by analysis, physio-chemical techniques and reactivity of these complexes. The location of bonding site of ligands, stability of complexes and status of U-O bond and probable structures of these complexes have been discussed. (author). 10 refs

  18. Evaluation of genetic toxicity of 6-diazo-5-oxo-l-norleucine (DON).

    Science.gov (United States)

    Kulkarni, Rohan M; Dakoulas, Emily W; Miller, Ken E; Terse, Pramod S

    2017-09-01

    DON (6-diazo-5-oxo-l-norleucine), a glutamine antagonist, was demonstrated to exhibit analgesic, antibacterial, antiviral and anticancer properties. The study was performed to characterize its in vitro and in vivo genetic toxicity potential. DON was tested in the bacterial reverse mutation assay (Ames test) using Salmonella typhimurium tester strains (TA98, TA100, TA1535 and TA1537) and Escherichia coli tester strain (WP2 uvrA) with and without S9 and also with reductive S9. In addition, DON was tested for the chromosome aberrations in Chinese hamster ovary (CHO) cells with or without S9 to evaluate the clastogenic potential. Furthermore, DON was also evaluated for its in vivo clastogenic activity by detecting micronuclei in polychromatic erythrocyte (PCE) cells in bone marrow collected from the male mice dosed intravenously with 500, 100, 10, 1 and 0.1 mg/kg at 24 and 48-h post-dose. The Ames mutagenicity assay showed no positive mutagenic responses. However, the in vitro chromosome aberration assay demonstrated dose dependent statistically positive increase in structural aberrations at 4 and 20-h exposure without S9 and also at 4-h exposure with S9. The in vivo micronucleus assay also revealed a statistically positive response for micronucleus formation at 500, 100 and 10 mg/kg at 24 and 48-h post-dose. Thus, DON appears to be negative in the Ames test but positive in the in vitro chromosome aberration assay and in the in vivo micronucleus assay. In conclusion, the results indicate DON is a genotoxic compound with a plausible epigenetic mechanism.

  19. Light-Induced C-H Arylation of (Hetero)arenes by In Situ Generated Diazo Anhydrides.

    Science.gov (United States)

    Cantillo, David; Mateos, Carlos; Rincon, Juan A; de Frutos, Oscar; Kappe, C Oliver

    2015-09-07

    Diazo anhydrides (Ar-N=N-O-N=N-Ar) have been known since 1896 but have rarely been used in synthesis. This communication describes the development of a photochemical catalyst-free C-H arylation methodology for the preparation of bi(hetero)aryls by the one-pot reaction of anilines with tert-butyl nitrite and (hetero)arenes under neutral conditions. The key step in this procedure is the in situ formation and subsequent photochemical (>300 nm) homolytic cleavage of a transient diazo anhydride intermediate. The generated aryl radical then efficiently reacts with a (hetero)arene to form the desired bi(hetero)aryls producing only nitrogen, water, and tert-butanol as byproducts. The scope of the reaction for several substituted anilines and (hetero)arenes was investigated. A continuous-flow protocol increasing selectivity and safety has been developed enabling the experimentally straightforward preparation of a variety of substituted bi(hetero)aryls within 45 min of reaction time. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Reviving Lonidamine and 6-Diazo-5-oxo-L-norleucine to Be Used in Combination for Metabolic Cancer Therapy

    Directory of Open Access Journals (Sweden)

    Diana Cervantes-Madrid

    2015-01-01

    Full Text Available Abnormal metabolism is another cancer hallmark. The two most characterized altered metabolic pathways are high rates of glycolysis and glutaminolysis, which are natural targets for cancer therapy. Currently, a number of newer compounds to block glycolysis and glutaminolysis are being developed; nevertheless, lonidamine and 6-diazo-5-oxo-L-norleucine (DON are two old drugs well characterized as inhibitors of glycolysis and glutaminolysis, respectively, whose clinical development was abandoned years ago when the importance of cancer metabolism was not fully appreciated and clinical trial methodology was less developed. In this review, a PubMed search using the words lonidamine and 6-diazo-5-oxo-L-norleucine (DON was undertaken to analyse existing information on the preclinical and clinical studies of these drugs for cancer treatment. Data show that they exhibit antitumor effects; besides there is also the suggestion that they are synergistic. We conclude that lonidamine and DON are safe and potentially effective drugs that need to be reevaluated in combination as metabolic therapy of cancer.

  1. Computational and experimental analysis identified 6-diazo-5-oxonorleucine as a potential agent for treating infection by Plasmodium falciparum.

    Science.gov (United States)

    Plaimas, Kitiporn; Wang, Yulin; Rotimi, Solomon O; Olasehinde, Grace; Fatumo, Segun; Lanzer, Michael; Adebiyi, Ezekiel; König, Rainer

    2013-12-01

    Plasmodium falciparum (PF) is the most severe malaria parasite. It is developing resistance quickly to existing drugs making it indispensable to discover new drugs. Effective drugs have been discovered targeting metabolic enzymes of the parasite. In order to predict new drug targets, computational methods can be used employing database information of metabolism. Using this data, we performed recently a computational network analysis of metabolism of PF. We analyzed the topology of the network to find reactions which are sensitive against perturbations, i.e., when a single enzyme is blocked by drugs. We now used a refined network comprising also the host enzymes which led to a refined set of the five targets glutamyl-tRNA (gln) amidotransferase, hydroxyethylthiazole kinase, deoxyribose-phophate aldolase, pseudouridylate synthase, and deoxyhypusine synthase. It was shown elsewhere that glutamyl-tRNA (gln) amidotransferase of other microorganisms can be inhibited by 6-diazo-5-oxonorleucine. Performing a half maximal inhibitory concentration (IC50) assay, we showed, that 6-diazo-5-oxonorleucine is also severely affecting viability of PF in blood plasma of the human host. We confirmed this by an in vivo study observing Plasmodium berghei infected mice. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Reviving Lonidamine and 6-Diazo-5-oxo-L-norleucine to Be Used in Combination for Metabolic Cancer Therapy

    Science.gov (United States)

    Cervantes-Madrid, Diana; Romero, Yair; Dueñas-González, Alfonso

    2015-01-01

    Abnormal metabolism is another cancer hallmark. The two most characterized altered metabolic pathways are high rates of glycolysis and glutaminolysis, which are natural targets for cancer therapy. Currently, a number of newer compounds to block glycolysis and glutaminolysis are being developed; nevertheless, lonidamine and 6-diazo-5-oxo-L-norleucine (DON) are two old drugs well characterized as inhibitors of glycolysis and glutaminolysis, respectively, whose clinical development was abandoned years ago when the importance of cancer metabolism was not fully appreciated and clinical trial methodology was less developed. In this review, a PubMed search using the words lonidamine and 6-diazo-5-oxo-L-norleucine (DON) was undertaken to analyse existing information on the preclinical and clinical studies of these drugs for cancer treatment. Data show that they exhibit antitumor effects; besides there is also the suggestion that they are synergistic. We conclude that lonidamine and DON are safe and potentially effective drugs that need to be reevaluated in combination as metabolic therapy of cancer. PMID:26425550

  3. Microbial fuel cell operation using monoazo and diazo dyes as terminal electron acceptor for simultaneous decolourisation and bioelectricity generation.

    Science.gov (United States)

    Oon, Yoong-Sin; Ong, Soon-An; Ho, Li-Ngee; Wong, Yee-Shian; Oon, Yoong-Ling; Lehl, Harvinder Kaur; Thung, Wei-Eng; Nordin, Noradiba

    2017-03-05

    Monoazo and diazo dyes [New coccine (NC), Acid orange 7 (AO7), Reactive red 120 (RR120) and Reactive green 19 (RG19)] were employed as electron acceptors in the abiotic cathode of microbial fuel cell. The electrons and protons generated from microbial organic oxidation at the anode which were utilized for electrochemical azo dye reduction at the cathodic chamber was successfully demonstrated. When NC was employed as the electron acceptor, the chemical oxygen demand (COD) removal and dye decolourisation efficiencies obtained at the anodic and cathodic chamber were 73±3% and 95.1±1.1%, respectively. This study demonstrated that the decolourisation rates of monoazo dyes were ∼50% higher than diazo dyes. The maximum power density in relation to NC decolourisation was 20.64mW/m 2 , corresponding to current density of 120.24mA/m 2 . The decolourisation rate and power output of different azo dyes were in the order of NC>AO7>RR120>RG19. The findings revealed that the structure of dye influenced the decolourisation and power performance of MFC. Azo dye with electron-withdrawing group at para substituent to azo bond would draw electrons from azo bond; hence the azo dye became more electrophilic and more favourable for dye reduction. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Typhidot M and Diazo test vis-à-vis blood culture and Widal test in the early diagnosis of typhoid fever in children in a resource poor setting.

    Science.gov (United States)

    Beig, Farzana K; Ahmad, Faraz; Ekram, Mohd; Shukla, Indu

    2010-01-01

    Typhoid fever is a major public health problem. A test which is simple, reliable and can be carried out in small laboratories is the need of the hour. We prospectively evaluated typhidot M and Diazo tests vis-à-vis blood culture and Widal test in children. Patients aged 6 months to 12 years, having fever of more than four days duration with clinical suspicion of typhoid fever were enrolled. Patients in whom other diagnosis was made served as control. The tests under scrutiny were validated against blood culture and then all the four tests were evaluated among patients who presented in the first week of illness. Blood culture was positive in only 27.3% of the cases. Among these culture positive cases, typhidot M test had the highest sensitivity, specificity, PPV and NPV of 90% (95% CI = 74.4-96.5), 100% (95% CI = 90.1-100), 100% (95% CI = 87.5-100), and 92.1% (95% CI = 79.2-97.3) respectively. Diazo test ranked next with sensitivity, specificity, PPV and NPV of 86.7% (95% CI = 70.3-94.7), 85.7% (95% CI = 70.6-93.7), 83.9% (95% CI = 67.4-92.9), 88.2% (95% CI = 73.4-95.3) respectively. Among clinically suspected typhoid cases, the overall sensitivity, of blood culture, Widal, typhidot M, Diazo was 27.3% (95% CI = 19.8- 36.3), 64.6% (95% CI = 55.3-72.9), 89.1% (95% CI = 81.9-93.7), 80.9% (95% CI = 72.6-87.2) respectively. In the first week of illness, typhidot M showed the best sensitivity [86.2% (95% CI = 69.4-94.5)] followed by Diazo [79% (95% CI = 61.6-90.2)], Widal [41.4% (95% CI = 25.5-59.3)] and blood culture [31% (95% CI = 17.3-49.2)]. Both Typhidot M and Diazo are good screening tests for the diagnosis of typhoid fever. Typhidot M is superior to Diazo but the latter is more suitable to resource poor settings being economic and easy to perform.

  5. Typhidot M and Diazo test vis-à-vis blood culture and Widal test in the early diagnosis of typhoid fever in children in a resource poor setting

    Directory of Open Access Journals (Sweden)

    Farzana K Beig

    Full Text Available OBJECTIVE: Typhoid fever is a major public health problem. A test which is simple, reliable and can be carried out in small laboratories is the need of the hour. We prospectively evaluated typhidot M and Diazo tests vis-à-vis blood culture and Widal test in children. METHODS: Patients aged 6 months to 12 years, having fever of more than four days duration with clinical suspicion of typhoid fever were enrolled. Patients in whom other diagnosis was made served as control. The tests under scrutiny were validated against blood culture and then all the four tests were evaluated among patients who presented in the first week of illness. RESULTS: Blood culture was positive in only 27.3% of the cases. Among these culture positive cases, typhidot M test had the highest sensitivity, specificity, PPV and NPV of 90% (95% CI = 74.4-96.5, 100% (95% CI = 90.1-100, 100% (95% CI = 87.5-100, and 92.1% (95% CI = 79.2-97.3 respectively. Diazo test ranked next with sensitivity, specificity, PPV and NPV of 86.7% (95% CI = 70.3-94.7, 85.7% (95% CI = 70.6-93.7, 83.9% (95% CI = 67.4-92.9, 88.2% (95% CI = 73.4-95.3 respectively. Among clinically suspected typhoid cases, the overall sensitivity, of blood culture, Widal, typhidot M, Diazo was 27.3% (95% CI = 19.8- 36.3, 64.6% (95% CI = 55.3-72.9, 89.1% (95% CI = 81.9-93.7, 80.9% (95% CI = 72.6-87.2 respectively. In the first week of illness, typhidot M showed the best sensitivity [86.2% (95% CI = 69.4-94.5] followed by Diazo [79% (95% CI = 61.6-90.2], Widal [41.4% (95% CI = 25.5-59.3] and blood culture [31% (95% CI = 17.3-49.2]. CONCLUSION: Both Typhidot M and Diazo are good screening tests for the diagnosis of typhoid fever. Typhidot M is superior to Diazo but the latter is more suitable to resource poor settings being economic and easy to perform.

  6. A non-diazo approach to α-oxo gold carbenes via gold-catalyzed alkyne oxidation.

    Science.gov (United States)

    Zhang, Liming

    2014-03-18

    For the past dozen years, homogeneous gold catalysis has evolved from a little known topic in organic synthesis to a fully blown research field of significant importance to synthetic practitioners, due to its novel reactivities and reaction modes. Cationic gold(I) complexes are powerful soft Lewis acids that can activate alkynes and allenes toward efficient attack by nucleophiles, leading to the generation of alkenyl gold intermediates. Some of the most versatile aspects of gold catalysis involve the generation of gold carbene intermediates, which occurs through the approach of an electrophile to the distal end of the alkenyl gold moiety, and their diverse transformations thereafter. On the other hand, α-oxo metal carbene/carbenoids are highly versatile intermediates in organic synthesis and can undergo various synthetically challenging yet highly valuable transformations such as C-H insertion, ylide formation, and cyclopropanation reactions. Metal-catalyzed dediazotizations of diazo carbonyl compounds are the principle and most reliable strategy to access them. Unfortunately, the substrates contain a highly energetic diazo moiety and are potentially explosive. Moreover, chemists need to use energetic reagents to prepare them, putting further constrains on operational safety. In this Account, we show that the unique access to the gold carbene species in homogeneous gold catalysis offers an opportunity to generate α-oxo gold carbenes if both nucleophile and electrophile are oxygen. Hence, this approach would enable readily available and safer alkynes to replace hazardous α-diazo carbonyl compounds as precursors in the realm of gold carbene chemistry. For the past several years, we have demonstrated that alkynes can indeed effectively serve as precursors to versatile α-oxo gold carbenes. In our initial study, we showed that a tethered sulfoxide can be a suitable oxidant, which in some cases leads to the formation of α-oxo gold carbene intermediates. The

  7. Stability of anti-reflection coatings via the self-assembly encapsulation of silica nanoparticles by diazo-resins

    Science.gov (United States)

    Metzman, Jonathan S.; Ridley, Jason I.; Khalifa, Moataz B.; Heflin, James R.

    2015-12-01

    A modified silica nanoparticle (MSNP) solution was formed by the encapsulation of negatively charged silica nanoparticles by the UV-crosslinkable polycation oligomer diazo-resin (DAR). Appropriate DAR encapsulation concentrations were determined by use of zeta-potential and dynamic light scattering measurements. The MSNPs were used in conjunction with poly(styrene sulfonate) (PSS) to grow homogenous ionic self-assembled multilayer anti-reflection coatings. Stability was induced within the films by the exposure of UV-irradiation that allowed for crosslinking of the DAR and PSS. The films were characterized by UV/vis/IR spectroscopy and field emission scanning electron microscopy. The transmission and reflection levels were >98.5% and <0.05%, respectively. The refractive indices resided in the 1.25-1.26 range. The solvent stability was tested by sonication of the films in a ternary solvent (H2O/DMF/ZnCl2 3:5:2 w/w/w).

  8. Intramolecular carbenoid ylide forming reactions of 2-diazo-3-keto-4-phthalimidocarboxylic esters derived from methionine and cysteine

    Directory of Open Access Journals (Sweden)

    Marc Enßle

    2012-03-01

    Full Text Available Methionine, S-benzylcysteine and S-allylcysteine were converted into 2-diazo-3-oxo-4-phthalimidocarboxylic esters 8a–c in three steps. Upon rhodium-catalysed dediazoniation, two intramolecular carbenoid reactions competed, namely the formation of a cyclic sulfonium ylide and that of a six-ring carbonyl ylide. The S-methyl and S-benzyl ylides 12a and b could be isolated, while S-allyl ylide 12c underwent a [2,3]-sigmatropic rearrangement. The short-lived carbonyl ylides derived from methionine and S-benzylcysteine formed head-to-tail dimers by a [3 + 3]-cycloaddition and could be trapped with external dipolarophiles, while the S-allyl derivative 14c yielded the pentacyclic compound 17 by an intramolecular [3 + 2]-cycloaddition reaction.

  9. Z-Selective iridium-catalyzed cross-coupling of allylic carbonates and α-diazo esters.

    Science.gov (United States)

    Thomas, Bryce N; Moon, Patrick J; Yin, Shengkang; Brown, Alex; Lundgren, Rylan J

    2018-01-07

    A well-defined Ir-allyl complex catalyzes the Z -selective cross-coupling of allyl carbonates with α-aryl diazo esters. The process overrides the large thermodynamic preference for E -products typically observed in metal-mediated coupling reactions to enable the synthesis of Z , E -dieneoates in good yield with selectivities consistently approaching or greater than 90 : 10. This transformation represents the first productive merger of Ir-carbene and Ir-allyl species, which are commonly encountered intermediates in allylation and cyclopropanation/E-H insertion catalysis. Potentially reactive functional groups (aryl halides, ketones, nitriles, olefins, amines) are tolerated owing to the mildness of reaction conditions. Kinetic analysis of the reaction suggests oxidative addition of the allyl carbonate to an Ir-species is rate-determining. Mechanistic studies uncovered a pathway for catalyst activation mediated by NEt 3 .

  10. A Non-Diazo Approach to α-Oxo Gold Carbenes via Gold-Catalyzed Alkyne Oxidation

    Science.gov (United States)

    2015-01-01

    For the past dozen years, homogeneous gold catalysis has evolved from a little known topic in organic synthesis to a fully blown research field of significant importance to synthetic practitioners, due to its novel reactivities and reaction modes. Cationic gold(I) complexes are powerful soft Lewis acids that can activate alkynes and allenes toward efficient attack by nucleophiles, leading to the generation of alkenyl gold intermediates. Some of the most versatile aspects of gold catalysis involve the generation of gold carbene intermediates, which occurs through the approach of an electrophile to the distal end of the alkenyl gold moiety, and their diverse transformations thereafter. On the other hand, α-oxo metal carbene/carbenoids are highly versatile intermediates in organic synthesis and can undergo various synthetically challenging yet highly valuable transformations such as C–H insertion, ylide formation, and cyclopropanation reactions. Metal-catalyzed dediazotizations of diazo carbonyl compounds are the principle and most reliable strategy to access them. Unfortunately, the substrates contain a highly energetic diazo moiety and are potentially explosive. Moreover, chemists need to use energetic reagents to prepare them, putting further constrains on operational safety. In this Account, we show that the unique access to the gold carbene species in homogeneous gold catalysis offers an opportunity to generate α-oxo gold carbenes if both nucleophile and electrophile are oxygen. Hence, this approach would enable readily available and safer alkynes to replace hazardous α-diazo carbonyl compounds as precursors in the realm of gold carbene chemistry. For the past several years, we have demonstrated that alkynes can indeed effectively serve as precursors to versatile α-oxo gold carbenes. In our initial study, we showed that a tethered sulfoxide can be a suitable oxidant, which in some cases leads to the formation of α-oxo gold carbene intermediates. The

  11. Structure of 6-diazo-5-oxo-norleucine-bound human gamma-glutamyl transpeptidase 1, a novel mechanism of inactivation.

    Science.gov (United States)

    Terzyan, Simon S; Cook, Paul F; Heroux, Annie; Hanigan, Marie H

    2017-06-01

    Intense efforts are underway to identify inhibitors of the enzyme gamma-glutamyl transpeptidase 1 (GGT1) which cleaves extracellular gamma-glutamyl compounds and contributes to the pathology of asthma, reperfusion injury and cancer. The glutamate analog, 6-diazo-5-oxo-norleucine (DON), inhibits GGT1. DON also inhibits many essential glutamine metabolizing enzymes rendering it too toxic for use in the clinic as a GGT1 inhibitor. We investigated the molecular mechanism of human GGT1 (hGGT1) inhibition by DON to determine possible strategies for increasing its specificity for hGGT1. DON is an irreversible inhibitor of hGGT1. The second order rate constant of inactivation was 0.052 mM -1 min -1 and the K i was 2.7 ± 0.7 mM. The crystal structure of DON-inactivated hGGT1 contained a molecule of DON without the diazo-nitrogen atoms in the active site. The overall structure of the hGGT1-DON complex resembled the structure of the apo-enzyme; however, shifts were detected in the loop forming the oxyanion hole and elements of the main chain that form the entrance to the active site. The structure of hGGT1-DON complex revealed two covalent bonds between the enzyme and inhibitor which were part of a six membered ring. The ring included the OG atom of Thr381, the reactive nucleophile of hGGT1 and the α-amine of Thr381. The structure of DON-bound hGGT1 has led to the discovery of a new mechanism of inactivation by DON that differs from its inactivation of other glutamine metabolizing enzymes, and insight into the activation of the catalytic nucleophile that initiates the hGGT1 reaction. © 2017 The Protein Society.

  12. RhII -Catalyzed β-C(sp2 )-H Alkylation of Enol Ethers, Enamides and Enecarbamates with α-Diazo Dicarbonyl Compounds.

    Science.gov (United States)

    McLarney, Brett D; Cavitt, Marchello A; Donnell, Theodore M; Musaev, Djamaladdin G; France, Stefan

    2017-01-23

    A Rh II -catalyzed method for intermolecular alkylation of the β-C(sp 2 )-H bond of enol ethers, enamides, and enecarbamates with α-diazo-1,3-dicarbonyl compounds is reported. The products are formed in up to 99 % yield and can be readily derivatized under a variety of conditions. By utilizing a combination of experimental and computational studies, the presumptive addition-elimination reaction mechanism was investigated and found to proceed under thermodynamic control at higher temperature. The acquired fundamental knowledge was translated into a strategic reaction design and yielded the first example of the β-C-H functionalizations of acyclic enol ethers using α-diazo-1,3-dicarbonyl compounds. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Asymmetric Radical Cyclopropanation of Alkenes with In Situ-Generated Donor-Substituted Diazo Reagents via Co(II)-Based Metalloradical Catalysis.

    Science.gov (United States)

    Wang, Yong; Wen, Xin; Cui, Xin; Wojtas, Lukasz; Zhang, X Peter

    2017-01-25

    Donor-substituted diazo reagents, generated in situ from sulfonyl hydrazones in the presence of base, can serve as suitable radical precursors for Co(II)-based metalloradical catalysis (MRC). The cobalt(II) complex of D 2 -symmetric chiral porphyrin [Co(3,5-Di t Bu-Xu(2'-Naph)Phyrin)] is an efficient metalloradical catalyst that is capable of activating different N-arylsulfonyl hydrazones for asymmetric radical cyclopropanation of a broad range of alkenes, affording the corresponding cyclopropanes in high yields with effective control of both diastereo- and enantioselectivity. This Co(II)-based metalloradical system represents the first catalytic protocol that can effectively utilize donor-type diazo reagents for asymmetric olefin cyclopropanation.

  14. Silver-Catalyzed [2+1] Cyclopropenation of Alkynes with Unstable Diazoalkanes: N-Nosylhydrazones as Room-Temperature Decomposable Diazo Surrogates.

    Science.gov (United States)

    Liu, Zhaohong; Li, Qiangqiang; Liao, Peiqiu; Bi, Xihe

    2017-04-06

    The [2+1] cycloaddition of alkynes with diazo compounds represents one of the most powerful and reliable methods for the construction of cyclopropenes. However, it remains a formidable challenge to accomplish the cyclopropenation of alkynes with non-stabilized diazoalkanes, owing to the fact that such compounds are unstable and prone to detonation. Herein, we report a general silver-catalyzed cyclopropenation reaction of alkynes with unstable diazoalkanes, by for the first time the discovery and application of N-nosylhydrazones as room-temperature decomposiable diazo surrogates. This method allows for the efficient assembly a wide variety of cyclopropene derivatives that are otherwise difficult to access by conventional methods. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Potassium N-Iodo p-Toluenesulfonamide (TsNIK, Iodamine-T): A New Reagent for the Oxidation of Hydrazones to Diazo Compounds

    Science.gov (United States)

    Nicolle, Simon M; Moody, Christopher J

    2014-01-01

    A new reagent for the oxidation of hydrazones to diazo compounds is described. N-Iodo p-toluenesulfonamide (TsNIK, iodamine-T) allows the preparation of α-diazoesters, α-diazoamides, α-diazoketones and α-diazophosphonates in good yield and in high purity after a simple extractive work-up. α-Diazoesters were also obtained in high yield from the corresponding ketones through a one-pot process of hydrazone formation/oxidation. PMID:24615944

  16. Rapid and direct spectrophotometric method for kinetics studies and routine assay of peroxidase based on aniline diazo substrates.

    Science.gov (United States)

    Mirazizi, Fatemeh; Bahrami, Azita; Haghbeen, Kamahldin; Shahbani Zahiri, Hossein; Bakavoli, Mehdi; Legge, Raymond L

    2016-12-01

    Peroxidases are ubiquitous enzymes that play an important role in living organisms. Current spectrophotometrically based peroxidase assay methods are based on the production of chromophoric substances at the end of the enzymatic reaction. The ambiguity regarding the formation and identity of the final chromophoric product and its possible reactions with other molecules have raised concerns about the accuracy of these methods. This can be of serious concern in inhibition studies. A novel spectrophotometric assay for peroxidase, based on direct measurement of a soluble aniline diazo substrate, is introduced. In addition to the routine assays, this method can be used in comprehensive kinetics studies. 4-[(4-Sulfophenyl)azo]aniline (λmax = 390 nm, ɛ = 32 880 M(-1) cm(-1) at pH 4.5 to 9) was introduced for routine assay of peroxidase. This compound is commercially available and is indexed as a food dye. Using this method, a detection limit of 0.05 nmol mL(-1) was achieved for peroxidase.

  17. Simultaneous production of laccase and decolouration of the diazo dye Reactive Black 5 in a fixed-bed bioreactor

    Energy Technology Data Exchange (ETDEWEB)

    Enayatzamir, Kheirghadam [Department of Chemical Engineering, Rovira i Virgili University, Av. Paisos Catalans 26, 43007 Tarragona (Spain); Department of Soil Science Engineering, University of Tehran, Karaj (Iran, Islamic Republic of); Alikhani, Hossein A. [Department of Soil Science Engineering, University of Tehran, Karaj (Iran, Islamic Republic of); Rodriguez Couto, Susana [Department of Chemical Engineering, Rovira i Virgili University, Av. Paisos Catalans 26, 43007 Tarragona (Spain)], E-mail: susana.rodriguez@urv.cat

    2009-05-15

    In this paper the production of laccase and the decolouration of the recalcitrant diazo dye Reactive Black 5 (RB5) by the white-rot fungus Trametes pubescens immobilised on stainless steel sponges in a fixed-bed reactor were studied. Laccase production was increased by 10-fold in the presence of RB5 and reached a maximum value of 1025 U/l. Enhanced laccase production in the presence of RB5 in this fungus is an added advantage during biodegradation of RB5-containing effluents. The decolouration of RB5 was due to two processes: dye adsorption onto the fungal mycelium and dye degradation by the laccase enzymes produced by the fungus. RB5 decolouration was performed during four successive batches obtaining high decolouration percentages (74%, 43% and 52% in 24 h for the first, third and four batch, respectively) without addition of redox mediators. Also, the in vitro decolouration of RB5 by the concentrated culture extract, containing mainly laccase, produced in the above bioreactor was studied. The decolouration percentages obtained were considerably lower (around 20% in 24 h) than that attained with the whole culture.

  18. Construction of covalently attached enzyme multilayer films based on the photoreaction of diazo-resins and glucose oxidase

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Suxia [Key Lab of Supramolecular Structure and Materials, College of Chemistry, Jilin University, 119 Jie Fang Road, Changchun 130023 (China); Niu Yaming [Key Lab of Supramolecular Structure and Materials, College of Chemistry, Jilin University, 119 Jie Fang Road, Changchun 130023 (China); Sun Changqing [Key Lab of Supramolecular Structure and Materials, College of Chemistry, Jilin University, 119 Jie Fang Road, Changchun 130023 (China)]. E-mail: sunchq@mail.jlu.edu.cn

    2004-10-15

    A novel and facile approach to construct multilayered glucose oxidase (GOx) films on the surface of quartz or CaF{sub 2} slides as well as gold electrodes for use as biosensing interfaces is described. Diazo-resins (DAR) as polycation and glucose oxidase as polyanion were alternately deposited into a multilayer structure using layer-by-layer self-assembly technique based on electrostatic interaction as driving force. Upon near UV irradiation, the adjacent interfaces of the multilayer reacted to form a crosslinking structure which greatly improved the stability of the enzyme films. These changes was monitored and confirmed by UV-vis and IR spectroscopy. Ellipsometric measurements reveal that the enzymes formed sub-molecule layers, and the thickness of the film shows a linear relationship with the number of assembled layers, demonstrating a spatially well-ordered manner in multilayer structure. The covalently attached enzyme multilayer film has a highly permeable structure, and can be used as biosensing interface. Electrochemical and analytical behavior of the enzyme electrodes was studied by cyclic voltammetry (CV) in the presence or absence of glucose. The sensitivity of the enzyme-modified electrodes was estimated through the analysis of voltammetric signals, which can be fine turned to the desired level by adjusting the number of attached bilayers.

  19. Construction of covalently attached enzyme multilayer films based on the photoreaction of diazo-resins and glucose oxidase

    International Nuclear Information System (INIS)

    Zhang Suxia; Niu Yaming; Sun Changqing

    2004-01-01

    A novel and facile approach to construct multilayered glucose oxidase (GOx) films on the surface of quartz or CaF 2 slides as well as gold electrodes for use as biosensing interfaces is described. Diazo-resins (DAR) as polycation and glucose oxidase as polyanion were alternately deposited into a multilayer structure using layer-by-layer self-assembly technique based on electrostatic interaction as driving force. Upon near UV irradiation, the adjacent interfaces of the multilayer reacted to form a crosslinking structure which greatly improved the stability of the enzyme films. These changes was monitored and confirmed by UV-vis and IR spectroscopy. Ellipsometric measurements reveal that the enzymes formed sub-molecule layers, and the thickness of the film shows a linear relationship with the number of assembled layers, demonstrating a spatially well-ordered manner in multilayer structure. The covalently attached enzyme multilayer film has a highly permeable structure, and can be used as biosensing interface. Electrochemical and analytical behavior of the enzyme electrodes was studied by cyclic voltammetry (CV) in the presence or absence of glucose. The sensitivity of the enzyme-modified electrodes was estimated through the analysis of voltammetric signals, which can be fine turned to the desired level by adjusting the number of attached bilayers

  20. Simultaneous production of laccase and decolouration of the diazo dye Reactive Black 5 in a fixed-bed bioreactor

    International Nuclear Information System (INIS)

    Enayatzamir, Kheirghadam; Alikhani, Hossein A.; Rodriguez Couto, Susana

    2009-01-01

    In this paper the production of laccase and the decolouration of the recalcitrant diazo dye Reactive Black 5 (RB5) by the white-rot fungus Trametes pubescens immobilised on stainless steel sponges in a fixed-bed reactor were studied. Laccase production was increased by 10-fold in the presence of RB5 and reached a maximum value of 1025 U/l. Enhanced laccase production in the presence of RB5 in this fungus is an added advantage during biodegradation of RB5-containing effluents. The decolouration of RB5 was due to two processes: dye adsorption onto the fungal mycelium and dye degradation by the laccase enzymes produced by the fungus. RB5 decolouration was performed during four successive batches obtaining high decolouration percentages (74%, 43% and 52% in 24 h for the first, third and four batch, respectively) without addition of redox mediators. Also, the in vitro decolouration of RB5 by the concentrated culture extract, containing mainly laccase, produced in the above bioreactor was studied. The decolouration percentages obtained were considerably lower (around 20% in 24 h) than that attained with the whole culture

  1. Stereodivergent Synthesis of N-Heterocycles by Catalyst-Controlled, Activity-Directed Tandem Annulation of Diazo Compounds with Amino Alkynes.

    Science.gov (United States)

    Liu, Kai; Zhu, Chenghao; Min, Junxiang; Peng, Shiyong; Xu, Guangyang; Sun, Jiangtao

    2015-10-26

    A stereodivergent synthesis of five-membered N-heterocycles, such as 2,3-dihydropyrroles, and 2-methylene and 3-methylene pyrrolidines, has been developed through a tandem annulation of amino alkynes with diazo compounds and involves the trapping of in situ formed intermediates. Mechanistic investigations indicate that the copper-catalyzed tandem annulations proceed by allenoate formation and subsequent intramolecular hydroamination. In contrast, the rhodium-catalyzed protocol features a carbenoid insertion into the NH bond and subsequent Conia-ene cyclization. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Synthesis and Molecular Structures of Two [1,4-bis(3-pyridyl)-2,3-diazo-1,3-butadiene]-dichloro-Zn(II) Coordination Polymers

    OpenAIRE

    Lee, Gene-Hsiang; Wang, Hsin-Ta

    2006-01-01

    Two novel coordination polymers with 3D metal-organic frameworks (MOFs) have been synthesized by reacting 1,4-bis(3-pyridyl)-2,3-diazo-1,3-butadiene (L) with zinc dichloride. Both compounds have the same repeating unit consisting of a distorted tetrahedral Zn(II) center coordinated by two chlorides and two pyridyl nitrogen atoms of two bridging bismonodentate L ligands, however, different structural conformations have been found, one forming a helical chain and the other producing a square-wa...

  3. Potentiometric detection of silver (I) ion based on carbon paste electrode modified with diazo-thiophenol-functionalized nanoporous silica gel

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Ting; Chai Yaqin, E-mail: yqchai@swu.edu.cn; Yuan Ruo; Guo Junxiang

    2012-07-01

    For the first time, triazene compound functionalized silica gel was incorporated into carbon paste electrode for the potentiometric detection of silver (I) ion. A novel diazo-thiophenol-functionalized silica gel (DTPSG) was synthesized, and the presence of DTPSG acted as not only a paste binder, but also a reactive material. The electrode with optimum composition, exhibited an excellent Nernstian response to Ag{sup +} ion ranging from 1.0 Multiplication-Sign 10{sup -6} to 1.0 Multiplication-Sign 10{sup -1} M with a detection limit of 9.5 Multiplication-Sign 10{sup -7} M and a slope of 60.4 {+-} 0.2 mV dec{sup -1} over a wide pH range (4.0-9.0) with a fast response time (50 s) at 25 Degree-Sign C. The electrode also showed a long-time stability, high selectivity and reproducibility. The response mechanism of the proposed electrode was investigated by using AC impedance. Moreover, the electrode was successfully applied for the determination of silver ions in radiology films, and for potentiometric titration of the mixture solution of Cl{sup -} and Br{sup -} ions. - Highlights: Black-Right-Pointing-Pointer Functionalized silica gels have become promising materials. Black-Right-Pointing-Pointer This work is the first attempt to apply triazene functionalized silica gel. Black-Right-Pointing-Pointer The Functionalized silica gels were used to detect silver. Black-Right-Pointing-Pointer The response of the previously reported papers are compared with this work. Black-Right-Pointing-Pointer The result indicates the proposed electrode is better than reported Ag{sup +} electrodes.

  4. Potentiometric detection of silver (I) ion based on carbon paste electrode modified with diazo-thiophenol-functionalized nanoporous silica gel

    International Nuclear Information System (INIS)

    Zhang Ting; Chai Yaqin; Yuan Ruo; Guo Junxiang

    2012-01-01

    For the first time, triazene compound functionalized silica gel was incorporated into carbon paste electrode for the potentiometric detection of silver (I) ion. A novel diazo-thiophenol-functionalized silica gel (DTPSG) was synthesized, and the presence of DTPSG acted as not only a paste binder, but also a reactive material. The electrode with optimum composition, exhibited an excellent Nernstian response to Ag + ion ranging from 1.0 × 10 −6 to 1.0 × 10 −1 M with a detection limit of 9.5 × 10 −7 M and a slope of 60.4 ± 0.2 mV dec −1 over a wide pH range (4.0–9.0) with a fast response time (50 s) at 25 °C. The electrode also showed a long-time stability, high selectivity and reproducibility. The response mechanism of the proposed electrode was investigated by using AC impedance. Moreover, the electrode was successfully applied for the determination of silver ions in radiology films, and for potentiometric titration of the mixture solution of Cl − and Br − ions. - Highlights: ► Functionalized silica gels have become promising materials. ► This work is the first attempt to apply triazene functionalized silica gel. ► The Functionalized silica gels were used to detect silver. ► The response of the previously reported papers are compared with this work. ► The result indicates the proposed electrode is better than reported Ag + electrodes.

  5. Switchable Synthesis of 4,5-Functionalized 1,2,3-Thiadiazoles and 1,2,3-Triazoles from 2-Cyanothioacetamides under Diazo Group Transfer Conditions.

    Science.gov (United States)

    Filimonov, Valeriy O; Dianova, Lidia N; Galata, Kristina A; Beryozkina, Tetyana V; Novikov, Mikhail S; Berseneva, Vera S; Eltsov, Oleg S; Lebedev, Albert T; Slepukhin, Pavel A; Bakulev, Vasiliy A

    2017-04-21

    High yield solvent-base-controlled, transition metal-free synthesis of 4,5-functionalized 1,2,3-thiadiazoles and 1,2,3-triazoles from 2-cyanothioacetamides and sulfonyl azides is described. Under diazo transfer conditions in the presence of a base in an aprotic solvent 2-cyanothioacetamides operating as C-C-S building blocks produce 5-amino-4-cyano-1,2,3-thiadiazoles exclusively. The use of alkoxide/alcohol system completely switches the reaction course due to the change of one of the reaction centers in the 2-cyanothioacetamide (C-C-N building block) resulting in the formation of 5-sulfonamido-1,2,3-triazole-4-carbothioamide sodium salts as the only products. The latter serve as good precursors for 5-amino-1,2,3-thiadiazole-4-carboximidamides, the products of Cornforth-type rearrangement occurring in neutral protic medium or under acid conditions. According to DFT calculations (B3LYP/6-311+G(d,p)) the rearrangement proceeds via intermediate formation of a diazo compound, and can be catalyzed by acids via the protonation of oxygen atom of the sulfonamide group.

  6. N-(Pivaloyloxy)alkoxy-carbonyl Prodrugs of the Glutamine Antagonist 6-Diazo-5-oxo-l-norleucine (DON) as a Potential Treatment for HIV Associated Neurocognitive Disorders.

    Science.gov (United States)

    Nedelcovych, Michael T; Tenora, Lukáš; Kim, Boe-Hyun; Kelschenbach, Jennifer; Chao, Wei; Hadas, Eran; Jančařík, Andrej; Prchalová, Eva; Zimmermann, Sarah C; Dash, Ranjeet P; Gadiano, Alexandra J; Garrett, Caroline; Furtmüller, Georg; Oh, Byoungchol; Brandacher, Gerald; Alt, Jesse; Majer, Pavel; Volsky, David J; Rais, Rana; Slusher, Barbara S

    2017-08-24

    Aberrant excitatory neurotransmission associated with overproduction of glutamate has been implicated in the development of HIV-associated neurocognitive disorders (HAND). The glutamine antagonist 6-diazo-5-oxo-l-norleucine (DON, 14) attenuates glutamate synthesis in HIV-infected microglia/macrophages, offering therapeutic potential for HAND. We show that 14 prevents manifestation of spatial memory deficits in chimeric EcoHIV-infected mice, a model of HAND. 14 is not clinically available, however, because its development was hampered by peripheral toxicities. We describe the synthesis of several substituted N-(pivaloyloxy)alkoxy-carbonyl prodrugs of 14 designed to circulate inert in plasma and be taken up and biotransformed to 14 in the brain. The lead prodrug, isopropyl 6-diazo-5-oxo-2-(((phenyl(pivaloyloxy)methoxy)carbonyl)amino)hexanoate (13d), was stable in swine and human plasma but liberated 14 in swine brain homogenate. When dosed systemically in swine, 13d provided a 15-fold enhanced CSF-to-plasma ratio and a 9-fold enhanced brain-to-plasma ratio relative to 14, opening a possible clinical path for the treatment of HAND.

  7. Diazo Reagents with Small Steric Footprints for Simultaneous Arming/SAR Studies of Alcohol-Containing Natural Products via O–H Insertion

    Science.gov (United States)

    Chamni, Supakarn; He, Qing-Li; Dang, Yongjun; Bhat, Shridhar; Liu, Jun O.; Romo, Daniel

    2011-01-01

    Natural products are essential tools for basic cellular studies leading to the identification of medically relevant protein targets and the discovery of potential therapeutic leads. The development of methods that enable mild and selective derivatization of natural products continues to be of significant interest for mining their information-rich content. Herein, we describe novel diazo reagents for simultaneous arming and structure-activity relationship (SAR) studies of alcohol-containing natural products with a small steric footprint, namely an α-trifluoroethyl (HTFB) substituted reagent. The Rh(II)-catalyzed O–H insertion reaction of several natural products, including the potent translation inhibitor lactimidomycin, was investigated and useful reactivity and both chemo- and site (chemosite) selectivities were observed. Differential binding to the known protein targets of both FK506 and fumagillol was demonstrated, validating the advantage of the smaller steric footprint of trifluoroethyl derivatives. A p-azidophenyl diazo reagent is also described that will prove useful for photoaffinity labeling of low affinity small molecule protein receptors. PMID:21894934

  8. The collagen type I segment long spacing (SLS) and fibrillar forms: Formation by ATP and sulphonated diazo dyes.

    Science.gov (United States)

    Harris, J Robin; Lewis, Richard J

    2016-07-01

    The collagen type I segment long spacing (SLS) crystallite is a well-ordered rod-like molecular aggregate, ∼300nm in length, which is produced in vitro under mildly acidic conditions (pH 2.5-3.5) in the presence of 1mM ATP. The formation of the SLS crystallite amplifies the inherent linear structural features of individual collagen heterotrimers, due to the punctate linear distribution and summation of the bulkier amino acid side chains along the length of individual collagen heterotrimers. This can be correlated structurally with the 67nm D-banded collagen fibril that is found in vivo, and formed in vitro. Although first described many years ago, the range of conditions required for ATP-induced SLS crystallite formation from acid-soluble collagen have not been explored extensively. Consequently, we have addressed biochemical parameters such as the ATP concentration, pH, speed of formation and stability so as to provide a more complete structural understanding of the SLS crystallite. Treatment of collagen type I with 1mM ATP at neutral and higher pH (6.0-9.0) also induced the formation of D-banded fibrils. Contrary to previous studies, we have shown that the polysulphonated diazo dyes Direct red (Sirius red) and Evans blue, but not Congo red and Methyl blue, can also induce the formation of SLS-like aggregates of collagen, but under markedly different ionic conditions to those employed in the presence of ATP. Specifically, pre-formed D-banded collagen fibrils, prepared in a higher than the usual physiological NaCl concentration (e.g. 500mM NaCl, 20mM Tris-HCl pH7.4 or x3 PBS), readily form SLS aggregates when treated with 0.1mM Direct red and Evans blue, but this did not occur at lower NaCl concentrations. These new data are discussed in relation to the anion (Cl(-)) and polyanion (phosphate and sulphonate) binding by the collagen heterotrimer and their likely role in collagen fibrillogenesis and SLS formation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Other components

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    This chapter includes descriptions of electronic and mechanical components which do not merit a chapter to themselves. Other hardware requires mention because of particularly high tolerance or intolerance of exposure to radiation. A more systematic analysis of radiation responses of structures which are definable by material was given in section 3.8. The components discussed here are field effect transistors, transducers, temperature sensors, magnetic components, superconductors, mechanical sensors, and miscellaneous electronic components

  10. Batch and Flow Photochemical Benzannulations Based on the Reaction of Ynamides and Diazo Ketones. Application to the Synthesis of Polycyclic Aromatic and Heteroaromatic Compounds

    Science.gov (United States)

    Willumstad, Thomas P.; Haze, Olesya; Mak, Xiao Yin; Lam, Tin Yiu; Wang, Yu-Pu; Danheiser*, Rick L.

    2013-01-01

    Highly substituted polycyclic aromatic and heteroaromatic compounds are produced via a two-stage tandem benzannulation/cyclization strategy. The initial benzannulation step proceeds via a pericyclic cascade mechanism triggered by thermal or photochemical Wolff rearrangement of a diazo ketone. The photochemical process can be performed using a continuous flow reactor which facilitates carrying out reactions on a large scale and minimizes the time required for photolysis. Carbomethoxy ynamides as well as more ketenophilic bissilyl ynamines and N-sulfonyl and N-phosphoryl ynamides serve as the reaction partner in the benzannulation step. In the second stage of the strategy, RCM generates benzofused nitrogen heterocycles, and various heterocyclization processes furnish highly substituted and polycyclic indoles of types that were not available by using the previous cyclobutenone-based version of the tandem strategy. PMID:24116731

  11. Synthesis of Functionalized Pyrazoles via 1,3-Dipolar Cycloaddition of α-Diazo-β-ketophosphonates, Sufones and Esters with Electron-Deficient Alkenes.

    Science.gov (United States)

    Baiju, T V; Namboothiri, Irishi N N

    2017-10-01

    1,3-Dipolar cycloaddition of diazo compounds with olefinic substrates is a promising atom-economic strategy for the construction of functionalized pyrazoles. Over the last few years, our group has been engaged in the synthesis of phosphonyl/sulfonylpyrazoles and pyrazole esters by employing Bestmann-Ohira Reagent (BOR) and its sulfur and ester analogs as 1,3-dipole precursors with various dipolarophiles. This account describes the novel synthetic methods developed in our laboratory, in the perspective of closely related work by others, for the synthesis of phosphonyl/sulfonylpyrazoles, pyrazole esters and the total synthesis of Withasomnine, a natural product, by using 1,3-dipolar cycloaddition as the key step. © 2017 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Synthesis of a tritium labeled photolabile analogue of farnesyl diphosphate: (E,E)-[1-3H]-(2-diazo-3-trifluoropropionyloxy)geranyl diphosphate (DATFP-GDP)

    International Nuclear Information System (INIS)

    Liu, J.; Benedict, C.R.

    1996-01-01

    Tritiated (E,E)-(2-diazo-3-trifluoropropionyloxy)geranyl disphosphate (DATFP-GDP) has been used as a photolabile analogue of (E,E)-farnesyl diphosphate (E,E-FDP) for an aid in isolating enzymes utilizing E,E-FDP as a substrate. We now report an alternative method of synthesizing this probe in which the tritium label is introduced in the step just before the introduction of the diphospate group. Thus, DATFP-geranial is oxidized to DATFP-geranial with activated manganese dioxide. The tritium label is introduced by reduction of the aldehyde with NaBT 4 . The DATFP-group successfully withstands both of these steps. The overall yield for these two steps is 69%. Diphosphorylation of the resulting alcohol afforded DATFP-[1- 3 H]-GDP in 8% yield with a specific activity of 48.6 μCi/μmol and radiochemical purity of 94%. (Author)

  13. Phytoremediation potential of Portulaca grandiflora Hook. (Moss-Rose) in degrading a sulfonated diazo reactive dye Navy Blue HE2R (Reactive Blue 172).

    Science.gov (United States)

    Khandare, Rahul V; Kabra, Akhil N; Kurade, Mayur B; Govindwar, Sanjay P

    2011-06-01

    Wild and tissue cultured plants of Portulaca grandiflora Hook. have shown to be able to decolorize a sulfonated diazo dye Navy Blue HE2R (NBHE2R) up to 98% in 40 h. A significant induction in the activities of lignin peroxidase, tyrosinase and DCIP reductase was observed in the roots during dye decolorization. The wild plants and tissue cultures could independently decolorize and degrade NBHE2R into metabolites viz. N-benzylacetamide and 6-diazenyl-4-hydroxynaphthalene-2-sulfonic acid. A dye mixture and a textile effluent were also decolorized efficiently by P. grandiflora. The phytotoxicity study revealed reduction in the toxicity due to metabolites formed after dye degradation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. The Elusive Palladium-Diazo Adduct Captured: Synthesis, Isolation and Structural Characterization of [(ArNHC-PPh2 )Pd(η2 -N2 C(Ph)CO2 Et)].

    Science.gov (United States)

    Rull, Silvia G; Álvarez, Eleuterio; Fructos, Manuel R; Belderrain, Tomás R; Pérez, Pedro J

    2017-06-07

    The first example of a diazo palladium adduct is reported. The complexes [(ArNHC-PPh 2 )M(η 2 -N 2 C(Ph)CO 2 Et)] (M=Ni, 3; M=Pd, 4; ArNHC-PPh 2 =3-(2,6-diisopropylphenyl)-1-[(diphenylphosphino)ethyl]imidazol-2-ylidene) were prepared by ligand exchange with styrene-coordinated precursors [(ArNHC-PPh 2 )M(styrene)] (M=Ni, 1; M=Pd, 2). Complex 4 was fully characterized, including X-ray analyses; this constitutes the first example of a diazo adduct compound with palladium, thereby closing the gap between Groups 8 and 10 regarding this type of compounds. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Electronic components

    CERN Document Server

    Colwell, Morris A

    1976-01-01

    Electronic Components provides a basic grounding in the practical aspects of using and selecting electronics components. The book describes the basic requirements needed to start practical work on electronic equipment, resistors and potentiometers, capacitance, and inductors and transformers. The text discusses semiconductor devices such as diodes, thyristors and triacs, transistors and heat sinks, logic and linear integrated circuits (I.C.s) and electromechanical devices. Common abbreviations applied to components are provided. Constructors and electronics engineers will find the book useful

  16. The Diazo Copying Process.

    Science.gov (United States)

    Osterby, Bruce

    1989-01-01

    Described is an activity which demonstrates an organic-based reprographic method that is used extensively for the duplication of microfilm and engineering drawings. Discussed are the chemistry of the process and how to demonstrate the process for students. (CW)

  17. Meiofaunal Responses to Leaf Litter Added to Azoic Sediments in a ...

    African Journals Online (AJOL)

    ANOVA revealed a significant (p <0.05) litter source effect between ... marine benthic systems and supports a high ... Western Indian Ocean J. Mar. ... leaf litter for various invertebrate groups that .... increasing the acidity of the plant material,.

  18. Advances in solar photoelectro-Fenton: Decolorization and mineralization of the Direct Yellow 4 diazo dye using an autonomous solar pre-pilot plant

    International Nuclear Information System (INIS)

    Garcia-Segura, Sergi; Brillas, Enric

    2014-01-01

    Highlights: • Assessment of an autonomous solar pre-pilot plant for solar photoelectro-Fenton. • Total decolorization and 96-97% mineralization for solutions of Direct Yellow 4 diazo dye at pH 3.0. • More rapid dye decay and mineralization at 0.50 mmol dm −3 Fe 2+ and maximum current of 5.0 A. • 11 aromatics, 22 hydroxylated derivatives and 9 carboxylic acids detected as intermediates. • Release of NH 4 + and SO 4 2− as main inorganic ions. - Abstract: Here, an overview on the advances in solar photoelectro-Fenton (SPEF) is initially presented to show that it is the more potent electrochemical advanced oxidation process based on Fenton's reaction chemistry to remove organic pollutants from waters, due to the synergistic action of generated hydroxyl radicals and solar irradiation. As a novel advance for SPEF, an autonomous solar pre-pilot plant is proposed to make an energetically inexpensive process that can be viable at industrial level. The plant of 10 dm 3 capacity contained a Pt/air-diffusion cell with 90.2 cm 2 electrode area, coupled to a solar compound parabolic collectors (CPCs) photoreactor of 1.57 dm 3 irradiation volume and to a solar photovoltaic panel that provides a maximum average current of 5.0 A. The oxidation ability of this plant was assessed by studying the degradation of Direct Yellow 4 (DY4) diazo dye, which involved the predominant destruction of organics by ·OH formed from Fenton's reaction between H 2 O 2 generated at the cathode and added Fe 2+ , along with the photolysis of Fe(III)-carboxylate complexes with sunlight in the CPCs photoreactor. The effect of Fe 2+ and dye contents as well as current on decolorization rate, substrate decay and mineralization rate was examined. About 96-97% mineralization was rapidly attained using 0.50 mmol dm −3 Fe 2+ and up to 0.32 mmol dm −3 DY4 at 5.0 A. The DY4 decay always obeyed a pseudo-first-order kinetics. Eleven aromatic products, twenty two hydroxylated derivatives

  19. Masked rhodamine dyes of five principal colors revealed by photolysis of a 2-diazo-1-indanone caging group: synthesis, photophysics, and light microscopy applications.

    Science.gov (United States)

    Belov, Vladimir N; Mitronova, Gyuzel Yu; Bossi, Mariano L; Boyarskiy, Vadim P; Hebisch, Elke; Geisler, Claudia; Kolmakov, Kirill; Wurm, Christian A; Willig, Katrin I; Hell, Stefan W

    2014-10-06

    Caged rhodamine dyes (Rhodamines NN) of five basic colors were synthesized and used as "hidden" markers in subdiffractional and conventional light microscopy. These masked fluorophores with a 2-diazo-1-indanone group can be irreversibly photoactivated, either by irradiation with UV- or violet light (one-photon process), or by exposure to intense red light (λ∼750 nm; two-photon mode). All dyes possess a very small 2-diazoketone caging group incorporated into the 2-diazo-1-indanone residue with a quaternary carbon atom (C-3) and a spiro-9H-xanthene fragment. Initially they are non-colored (pale yellow), non-fluorescent, and absorb at λ=330-350 nm (molar extinction coefficient (ε)≈10(4)  M(-1)  cm(-1)) with a band edge that extends to about λ=440 nm. The absorption and emission bands of the uncaged derivatives are tunable over a wide range (λ=511-633 and 525-653 nm, respectively). The unmasked dyes are highly colored and fluorescent (ε=3-8×10(4)  M(-1)  cm(-1) and fluorescence quantum yields (ϕ)=40-85% in the unbound state and in methanol). By stepwise and orthogonal protection of carboxylic and sulfonic acid groups a highly water-soluble caged red-emitting dye with two sulfonic acid residues was prepared. Rhodamines NN were decorated with amino-reactive N-hydroxysuccinimidyl ester groups, applied in aqueous buffers, easily conjugated with proteins, and readily photoactivated (uncaged) with λ=375-420 nm light or intense red light (λ=775 nm). Protein conjugates with optimal degrees of labeling (3-6) were prepared and uncaged with λ=405 nm light in aqueous buffer solutions (ϕ=20-38%). The photochemical cleavage of the masking group generates only molecular nitrogen. Some 10-40% of the non-fluorescent (dark) byproducts are also formed. However, they have low absorbance and do not quench the fluorescence of the uncaged dyes. Photoactivation of the individual molecules of Rhodamines NN (e.g., due to reversible or irreversible

  20. Principal components

    NARCIS (Netherlands)

    Hallin, M.; Hörmann, S.; Piegorsch, W.; El Shaarawi, A.

    2012-01-01

    Principal Components are probably the best known and most widely used of all multivariate analysis techniques. The essential idea consists in performing a linear transformation of the observed k-dimensional variables in such a way that the new variables are vectors of k mutually orthogonal

  1. Diazo compounds for the bioreversible esterification of proteins† †Electronic supplementary information (ESI) available: Experimental procedures, analytical data, and spectral data for novel compounds. See DOI: 10.1039/c4sc01768d Click here for additional data file.

    Science.gov (United States)

    McGrath, Nicholas A.; Andersen, Kristen A.; Davis, Amy K. F.; Lomax, Jo E.

    2015-01-01

    A diazo compound is shown to convert carboxylic acids to esters efficiently in an aqueous environment. The basicity of the diazo compound is critical: low basicity does not lead to a reaction but high basicity leads to hydrolysis. This reactivity extends to carboxylic acid groups in a protein. The ensuing esters are hydrolyzed by human cellular esterases to regenerate protein carboxyl groups. This new mode of chemical modification could enable the key advantages of prodrugs to be translated from small-molecules to proteins. PMID:25544883

  2. O-(4-diazo-3,5-di[125I]iodobenzoyl)sucrose, a novel radioactive label for determining organ sites of catabolism of plasma proteins

    International Nuclear Information System (INIS)

    Jong, A.S.H. de; Bouma, J.M.W.; Gruber, M.

    1981-01-01

    A method is described for radiolabelling proteins with O-(4-diazo-3,5-di[ 125 I]iodobenzoyl)sucrose (DD 125 IBS). When proteins so labelled were degraded within lysosomes, the radioactive fragments were largely retained within the organelle. High specific radioactivities were obtained without changing the properties of the protein. The validity of the method was demonstrated in vivo in rats using the short-lived protein lactate dehydrogenase, isoenzyme M 4 , and the long-lived protein bovine serum albumin. Derivatization with DD 125 IBS did not alter the clearance of either protein. Uptake of DD 125 IBS-labelled lactate dehydrogenase, isoenzyme M 4 , by liver and spleen of rats was determined. Radioactivity in these tissues increased up to about 2 h after injection (at this time the protein has been almost completely cleared from the blood) and subsequently declined with a half-life of approx. 20h. After differential fractionation of liver, radioactivity was largely found in the mitochondrial and lysosomal fraction. The results of these studies establish that DD 125 IBS covalently coupled to plasma proteins should be a useful radioactive tracer for identifying the tissue and cellular sites of catabolism of relatively long-lived circulating proteins. (author)

  3. Diazo dye Congo Red degradation using a Boron-doped diamond anode: An experimental study on the effect of supporting electrolytes.

    Science.gov (United States)

    Jalife-Jacobo, H; Feria-Reyes, R; Serrano-Torres, O; Gutiérrez-Granados, S; Peralta-Hernández, Juan M

    2016-12-05

    Diazo dye Congo Red (CR) solutions at 100mg/L, were degraded using different supporting electrolytes in an electrochemical advanced oxidation process (EAOPs), like the anodic oxidation (AOx/BDD). All experiments were carried out in a 3L flow reactor with a Boron-doped diamond (BDD) anode and stainless steel cathode (AISI 304), at 7.5, 15, 30 and 50mA/cm(2) current densities (j). Furthermore, each experiment was carried out under a flow rate of 7L/min. Additionally, HClO4, NaCl, Na2SO4, and H2SO4 were tested as supporting electrolytes at a 50mM concentration. The degradation process was at all times considerably faster in NaCl medium. Solutions containing SO4(2-) or ClO4(-) ions were less prompted to degradation due to the low oxidation power of these species into the bulk. Dissolved organic carbon (DOC) analysis, was carried out to evaluate the mineralization of CR. The degradation of CR, was evaluated with the HPLC analysis of the treated solutions. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Vibrational normal modes of diazo-dimedone: A comparative study by Fourier infrared/Raman spectroscopies and conformational analysis by MM/QM

    Science.gov (United States)

    Téllez Soto, C. A.; Ramos, J. M.; Rianelli, R. S.; de Souza, M. C. B. V.; Ferreira, V. F.

    2007-07-01

    The 2-diazo-5,5-dimethyl-cyclohexane-1,3-dione ( 3) was synthesized and the FT-IR/Raman spectra were measured with the purpose of obtain a full assignment of the vibrational modes. Singular aspects concerning the -C dbnd N dbnd N oscillator are discussed in view of two strong bands observed in the region of 2300-2100 cm -1 in both, Infrared and Raman spectra. The density functional theory (DFT) was used to obtain the geometrical structure and for assisting in the vibrational assignment joint to the traditional normal coordinate analysis (NCA). The observed wavenumbers at 2145 (IR), 2144(R) are assigned as the coupled ν(N dbnd N) + ν(C dbnd N) vibrational mode with higher participation of the N dbnd N stretching. A 2188 cm -1 (IR) and at 2186 cm -1 (R) can be assigned as a overtone of one of ν(CC) normal mode or to a combination band of the fundamentals δ(CCH) found at 1169 cm -1 and the δ (CC dbnd N) found at 1017 cm -1 enhanced by Fermi resonance.

  5. A novel amperometric biosensor based on covalently attached multilayer assemblies of gold nanoparticles, diazo-resins and acetylcholinesterase for the detection of organophosphorus pesticides.

    Science.gov (United States)

    Jiang, Bin; Dong, Pei; Zheng, Jianbin

    2018-06-01

    Using an ionic layer-by-layer self-assembly technique, colloidal gold nanoparticles (AuNPs) and diazo-resins (DAR) were immobilised on the surface of a p-aminobenzenesulfonic acid-modified glassy carbon electrode to form a matrix composite membrane for acetylcholinesterase (AChE) immobilisation. Photo-sensitive DAR was used as the assembly interlayer to convert the ionic bond into a covalent bond to improve the biosensor stability. These fabrication processes were followed by electrochemical impedance spectroscopy and cyclic voltammetry to verify the membrane formation. Because of the introduction of AuNPs/DAR/AChE biofilms, the modified electrode exhibited excellent electron transfer mediation and electrical conductivity. In addition, it exhibited high sensitivity in the range of linear concentration from 1.0 × 10 -8 to 1.0 × 10 -12 g L -1 with the detection limit of 5.12 × 10 -13 and 5.85 × 10 -13 g L -1 for malathion and methyl parathion, respectively. More importantly, the presented biosensor considerably improved stability because the electrostatic interaction was converted into covalent bonds by UV irradiation. It is a simple, cheap and stable method for quantitative detection of organophosphorus pesticides, and this method may pave a way for the sensitive, simple detection of different analytes without the need of expensive instrumentation. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Synthesis and Molecular Structures of Two [1,4-bis(3-pyridyl-2,3-diazo-1,3-butadiene]-dichloro-Zn(II Coordination Polymers

    Directory of Open Access Journals (Sweden)

    Hsin-Ta Wang

    2006-08-01

    Full Text Available Two novel coordination polymers with 3D metal-organic frameworks (MOFs have been synthesized by reacting 1,4-bis(3-pyridyl-2,3-diazo-1,3-butadiene (L with zinc dichloride. Both compounds have the same repeating unit consisting of a distorted tetrahedral Zn(II center coordinated by two chlorides and two pyridyl nitrogen atoms of two bridging bismonodentate L ligands, however, different structural conformations have been found, one forming a helical chain and the other producing a square-wave chain. The intermolecular C−H···Cl hydrogen bonds in 1 and 2 play important roles in the formation of three-dimensional coordination polymers. Compound 1 crystallized in an orthorhombic space group Pna21 with a = 7.9652(3, b = 21.4716(7, c = 8.2491(3Å, V = 1410.81(9 Å 3 and Z = 4. Compound 2 crystallized in a monoclinic space group P21/n with a = 9.1752(3, b = 14.5976(4, c = 10.3666(3 Å , β = 98.231(2°, V = 1374.16(7 Å 3 and Z = 4.

  7. Bioanalysis of 6-Diazo-5-oxo-L-norleucine (DON) in plasma and brain by ultra-performance liquid chromatography mass spectrometry

    Science.gov (United States)

    Alt, Jesse; Potter, Michelle C.; Rojas, Camilo; Slusher, Barbara S.

    2015-01-01

    Glutamine is an abundant amino acid that plays pivotal roles in cell growth, cell metabolism and neurotransmission. Dysregulation of glutamine-utilizing pathways has been associated with pathological conditions such as cancer and neurodegenerative diseases. 6-Diazo-5-Oxo-L-Norleucine (DON) is a reactive glutamine analog that inhibits enzymes affecting glutamine metabolism such as glutaminase, 2-N-amidotransferase, L-asparaginase and several enzymes involved in pyrimidine and purine de novo synthesis. As a result, DON is actively used in preclinical models of cancer and neurodegenerative disease. Moreover, there have been several clinical trials using DON to treat a variety of cancers. Considerations of dose and exposure are especially important with DON treatment due to its narrow therapeutic window and significant side effects. Consequently, a robust quantification bioassay is of interest. DON is a polar unstable molecule which has made quantification challenging. Here we report on the characterization of a bioanalytical method to quantify DON in tissue samples involving DON derivatization with 3N HCl in butanol. The derivatized product is lipophilic and stable. Detection of this analyte by mass spectrometry is fast, specific and can be used to quantify DON in plasma and brain tissue with a limit of detection in the low nanomolar level. PMID:25584882

  8. Comparative performance of anodic oxidation and electrocoagulation as clean processes for electrocatalytic degradation of diazo dye Acid Brown 14 in aqueous medium.

    Science.gov (United States)

    Bassyouni, D G; Hamad, H A; El-Ashtoukhy, E-S Z; Amin, N K; El-Latif, M M Abd

    2017-08-05

    In this study, a laboratory scale for the treatment of a recalcitrant and toxic synthetic wastewater containing diazo dye, acid brown 14 (AB-14) has been comparatively performed by two electro-catalytic treatment processes, namely anodic oxidation (AO) and electrocoagulation (EC) using a new batch electrochemical cell. Additionally, the influence of several operating parameters such as; current density (j), initial dye concentration (C o ), NaCl concentration (C N ), and pH on the color removal efficiency and chemical oxygen demand (COD) are evaluated. The powerful capability of the AO and EC of AB-14 which related to the mechanistic reaction pathway is shown. The poor degradation is ascribed to higher C o and pH, while the enhancement of j and C N is responsible for better degradation of AB-14 dye. The results indicate that the EC is more effective than AO under the same operational condition. A kinetic model is developed for evaluation of the pseudo-first-order-rate constant (k app ) as a function of various operational parameters. The results emphasize the high efficiency of AO and EC and the clean processes which are hopeful alternative for the treatment of the large volume wastewater of the textile industry. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Evaluating the Toxicity of the Analgesic Glutaminase Inhibitor 6-Diazo-5-Oxo-L-Norleucine in vitro and on Rat Dermal Skin Fibroblasts

    Science.gov (United States)

    Crosby, Heith A; Ihnat, Michael; Miller, Kenneth E

    2018-01-01

    6-diazo-5-oxo-l-norleucine (DON) is a glutamine antagonist produced naturally by Streptomyces. It inhibits several glutamine-dependent enzyme pathways. Of particular note is its inhibitory effect on the mitochondrial enzyme, glutaminase (GLS), the primary producer of neuronal glutamate. Glutamate is an excitatory neurotransmitter released by primary sensory peripheral nerve terminals and spinal synaptic terminals during pain signaling. Previous work using the tail incision and inflammatory models of pain has demonstrated that a single application of the glutaminase inhibitor, DON, into a surgical incision or the paw of arthritic animals results in pain relief. Even though this compound shows promise as a therapeutic agent, limited data exist regarding its dermal toxicity. As a first approach, we evaluated the effect of several concentrations of DON, on the viability, mitochondrial oxidative capacity and proliferation of rat skin fibroblasts, and then examined the effect of DON after incubation with human liver microsomes on proliferation. Finally, we evaluated DON treated rat skin (tail and hind paw) for cellular necrosis, inflammation and mitotic bodies. No significant effects (p > 0.05) of DON were noted on apoptosis, necrosis, and mitochondrial activity in experiments with cultured rat skin fibroblasts. Flow cytometry revealed the absence of apoptosis in cells treated at the IC50 of 232.5 μM. Enhanced toxicity post-exposure to human microsomes was not observed when compared to DON alone. The H&E staining of the rat skin revealed no obvious pathology in the DON treatment group (10 mM). DON has no/minimal cellular toxicity in vitro on dermal fibroblasts at concentrations that effectively provide analgesia. The local application of concentrations greater than the in vitro IC50 for DON revealed no in vivo skin toxicity. These data provide results indicating zero-to-minimal cellular toxicity with DON and support the further investigation of DON as an analgesic. PMID

  10. Rh(V) -Nitrenoid as a Key Intermediate in Rh(III) -Catalyzed Heterocyclization by C-H Activation: A Computational Perspective on the Cycloaddition of Benzamide and Diazo Compounds.

    Science.gov (United States)

    Zhou, Tao; Guo, Wei; Xia, Yuanzhi

    2015-06-15

    A mechanistic study of the substituent-dependent ring formations in Rh(III) -catalyzed C-H activation/cycloaddition of benzamide and diazo compounds was carried out by using DFT calculations. The results indicated that the decomposition of the diazo is facilitated upon the formation of the five-membered rhodacycle, in which the Rh(III) center is more electrophilic. The insertion of carbenoid into Rh-C(phenyl) bond occurs readily and forms a 6-membered rhodacycle, however, the following C-N bond formation is difficult both kinetically and thermodynamically by reductive elimination from the Rh(III) species. Instead, the Rh(V) -nitrenoid intermediate could be formed by migration of the pivalate from N to Rh, which undergoes the heterocyclization much more easily and complementary ring-formations could be modulated by the nature of the substituent at the α-carbon. When a vinyl is attached, the stepwise 1,3-allylic migration occurs prior to the pivalate migration and the 8-membered ring product will be formed. On the other hand, the pivalate migration becomes more favorable for the phenyl-contained intermediate because of the difficult 1,3-allylic migration accompanied by dearomatization, thus the 5-membered ring product was formed selectively. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Rhodium(III)-Catalyzed ortho-Alkylation of Phenoxy Substrates with Diazo Compounds via C-H Activation: A Case of Decarboxylative Pyrimidine/Pyridine Migratory Cyclization Rather than Removal of Pyrimidine/Pyridine Directing Group.

    Science.gov (United States)

    Ravi, Manjula; Allu, Srinivasarao; Swamy, K C Kumara

    2017-03-03

    An efficient Rh(III)-catalyzed ortho-alkylation of phenoxy substrates with diazo compounds has been achieved for the first time using pyrimidine or pyridine as the directing group. Furthermore, bis-alkylation has also been achieved using para-substituted phenoxypyrimidine and 3 mol equiv of the diazo ester. The ortho-alkylated derivatives of phenoxy products possessing the ester functionality undergo decarboxylative pyrimidine/pyridine migratory cyclization (rather than deprotection of pyrimidine/pyridine group) using 20% NaOEt in EtOH affording a novel class of 3-(pyrimidin-2(1H)-ylidene)benzofuran-2(3H)-ones and 6-methyl-3-(pyridin-2(1H)-ylidene)benzofuran-2(3H)-one. The ortho-alkylated phenoxypyridine possessing ester functionality also undergoes decarboxylative pyridine migratory cyclization using MeOTf/NaOMe in toluene providing 6-methyl-3-(1-methylpyridin-2(1H)-ylidene)benzofuran-2(3H)-one.

  12. Redox-neutral rhodium-catalyzed C-H functionalization of arylamine N-oxides with diazo compounds: primary C(sp(3))-H/C(sp(2))-H activation and oxygen-atom transfer.

    Science.gov (United States)

    Zhou, Bing; Chen, Zhaoqiang; Yang, Yaxi; Ai, Wen; Tang, Huanyu; Wu, Yunxiang; Zhu, Weiliang; Li, Yuanchao

    2015-10-05

    An unprecedented rhodium(III)-catalyzed regioselective redox-neutral annulation reaction of 1-naphthylamine N-oxides with diazo compounds was developed to afford various biologically important 1H-benzo[g]indolines. This coupling reaction proceeds under mild reaction conditions and does not require external oxidants. The only by-products are dinitrogen and water. More significantly, this reaction represents the first example of dual functiaonalization of unactivated a primary C(sp(3) )H bond and C(sp(2) )H bond with diazocarbonyl compounds. DFT calculations revealed that an intermediate iminium is most likely involved in the catalytic cycle. Moreover, a rhodium(III)-catalyzed coupling of readily available tertiary aniline N-oxides with α-diazomalonates was also developed under external oxidant-free conditions to access various aminomandelic acid derivatives by an O-atom-transfer reaction. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Reactive carbon-chain molecules: synthesis of 1-diazo-2,4-pentadiyne and spectroscopic characterization of triplet pentadiynylidene (H-C[triple bond]C-:C-C[triple bond]C-H).

    Science.gov (United States)

    Bowling, Nathan P; Halter, Robert J; Hodges, Jonathan A; Seburg, Randal A; Thomas, Phillip S; Simmons, Christopher S; Stanton, John F; McMahon, Robert J

    2006-03-15

    1-Diazo-2,4-pentadiyne (6a), along with both monodeuterio isotopomers 6b and 6c, has been synthesized via a route that proceeds through diacetylene, 2,4-pentadiynal, and 2,4-pentadiynal tosylhydrazone. Photolysis of diazo compounds 6a-c (lambda > 444 nm; Ar or N2, 10 K) generates triplet carbenes HC5H (1) and HC5D (1-d), which have been characterized by IR, EPR, and UV/vis spectroscopy. Although many resonance structures contribute to the resonance hybrid for this highly unsaturated carbon-chain molecule, experiment and theory reveal that the structure is best depicted in terms of the dominant resonance contributor of penta-1,4-diyn-3-ylidene (diethynylcarbene, H-C[triple bond]C-:C-C[triple bond]C-H). Theory predicts an axially symmetric (D(infinity h)) structure and a triplet electronic ground state for 1 (CCSD(T)/ANO). Experimental IR frequencies and isotope shifts are in good agreement with computed values. The triplet EPR spectrum of 1 (absolute value(D/hc) = 0.6157 cm(-1), absolute value(E/hc) = 0.0006 cm(-1)) is consistent with an axially symmetric structure, and the Curie law behavior confirms that the triplet state is the ground state. The electronic absorption spectrum of 1 exhibits a weak transition near 400 nm with extensive vibronic coupling. Chemical trapping of triplet HC5H (1) in an O2-doped matrix affords the carbonyl oxide 16 derived exclusively from attack at the central carbon.

  14. Mitigating component performance variation

    Science.gov (United States)

    Gara, Alan G.; Sylvester, Steve S.; Eastep, Jonathan M.; Nagappan, Ramkumar; Cantalupo, Christopher M.

    2018-01-09

    Apparatus and methods may provide for characterizing a plurality of similar components of a distributed computing system based on a maximum safe operation level associated with each component and storing characterization data in a database and allocating non-uniform power to each similar component based at least in part on the characterization data in the database to substantially equalize performance of the components.

  15. Reusable Component Services

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Reusable Component Services (RCS) is a super-catalog of components, services, solutions and technologies that facilitates search, discovery and collaboration in...

  16. Software component quality evaluation

    Science.gov (United States)

    Clough, A. J.

    1991-01-01

    The paper describes a software inspection process that can be used to evaluate the quality of software components. Quality criteria, process application, independent testing of the process and proposed associated tool support are covered. Early results indicate that this technique is well suited for assessing software component quality in a standardized fashion. With automated machine assistance to facilitate both the evaluation and selection of software components, such a technique should promote effective reuse of software components.

  17. Reactor component automatic grapple

    International Nuclear Information System (INIS)

    Greenaway, P.R.

    1982-01-01

    A grapple for handling nuclear reactor components in a medium such as liquid sodium which, upon proper seating and alignment of the grapple with the component as sensed by a mechanical logic integral to the grapple, automatically seizes the component. The mechanical logic system also precludes seizure in the absence of proper seating and alignment. (author)

  18. Repurposing learning object components

    NARCIS (Netherlands)

    Verbert, K.; Jovanovic, J.; Gasevic, D.; Duval, E.; Meersman, R.

    2005-01-01

    This paper presents an ontology-based framework for repurposing learning object components. Unlike the usual practice where learning object components are assembled manually, the proposed framework enables on-the-fly access and repurposing of learning object components. The framework supports two

  19. Flow chemistry as a discovery tool to access sp2–sp3 cross-coupling reactions via diazo compounds† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c4sc03072a Click here for additional data file.

    Science.gov (United States)

    Tran, Duc N.; Battilocchio, Claudio; Lou, Shing-Bong; Hawkins, Joel M.

    2015-01-01

    The work takes advantage of an important feature of flow chemistry, whereby the generation of a transient species (or reactive intermediate) can be followed by a transfer step into another chemical environment, before the intermediate is reacted with a coupling partner. This concept is successfully applied to achieve a room temperature sp2–sp3 cross coupling of boronic acids with diazo compounds, these latter species being generated from hydrazones under flow conditions using MnO2 as the oxidant. PMID:29560199

  20. Supply chain components

    OpenAIRE

    Vieraşu, T.; Bălăşescu, M.

    2011-01-01

    In this article I will go through three main logistics components, which are represented by: transportation, inventory and facilities, and the three secondary logistical components: information, production location, price and how they determine performance of any supply chain. I will discuss then how these components are used in the design, planning and operation of a supply chain. I will also talk about some obstacles a supply chain manager may encounter.

  1. Supply chain components

    Directory of Open Access Journals (Sweden)

    Vieraşu, T.

    2011-01-01

    Full Text Available In this article I will go through three main logistics components, which are represented by: transportation, inventory and facilities, and the three secondary logistical components: information, production location, price and how they determine performance of any supply chain. I will discuss then how these components are used in the design, planning and operation of a supply chain. I will also talk about some obstacles a supply chain manager may encounter.

  2. Control component retainer

    International Nuclear Information System (INIS)

    Walton, L.A.; King, R.A.

    1983-01-01

    An apparatus is described for retaining an undriven control component assembly disposed in a fuel assembly in a nuclear reactor of the type having a core grid plate. The first part of the mechanism involves a housing for the control component and the second part is a brace with a number of arms that reach under the grid plate. The brace and the housing are coupled together to firmly hold the control components in place even under strong flows of th coolant

  3. Component design for LMFBR's

    International Nuclear Information System (INIS)

    Fillnow, R.H.; France, L.L.; Zerinvary, M.C.; Fox, R.O.

    1975-01-01

    Just as FFTF has prototype components to confirm their design, FFTF is serving as a prototype for the design of the commercial LMFBR's. Design and manufacture of critical components for the FFTF system have been accomplished primarily using vendors with little or no previous experience in supplying components for high temperature sodium systems. The exposure of these suppliers, and through them a multitude of subcontractors, to the requirements of this program has been a necessary and significant step in preparing American industry for the task of supplying the large mechanical components required for commercial LMFBR's

  4. Hot gas path component

    Science.gov (United States)

    Lacy, Benjamin Paul; Kottilingam, Srikanth Chandrudu; Porter, Christopher Donald; Schick, David Edward

    2017-09-12

    Various embodiments of the disclosure include a turbomachine component. and methods of forming such a component. Some embodiments include a turbomachine component including: a first portion including at least one of a stainless steel or an alloy steel; and a second portion joined with the first portion, the second portion including a nickel alloy including an arced cooling feature extending therethrough, the second portion having a thermal expansion coefficient substantially similar to a thermal expansion coefficient of the first portion, wherein the arced cooling feature is located within the second portion to direct a portion of a coolant to a leakage area of the turbomachine component.

  5. Components of Sexual Identity

    Science.gov (United States)

    Shively, Michael G.; DeCecco, John P.

    1977-01-01

    This paper examines the four components of sexual identity: biological sex, gender identity, social sex-role, and sexual orientation. Theories about the development of each component and how they combine and conflict to form the individual's sexual identity are discussed. (Author)

  6. Towards Cognitive Component Analysis

    DEFF Research Database (Denmark)

    Hansen, Lars Kai; Ahrendt, Peter; Larsen, Jan

    2005-01-01

    Cognitive component analysis (COCA) is here defined as the process of unsupervised grouping of data such that the ensuing group structure is well-aligned with that resulting from human cognitive activity. We have earlier demonstrated that independent components analysis is relevant for representing...

  7. Feasibility and antitumor efficacy in vivo, of simultaneously targeting glycolysis, glutaminolysis and fatty acid synthesis using lonidamine, 6-diazo-5-oxo-L-norleucine and orlistat in colon cancer.

    Science.gov (United States)

    Cervantes-Madrid, Diana; Dominguez-Gomez, Guadalupe; Gonzalez-Fierro, Aurora; Perez-Cardenas, Enrique; Taja-Chayeb, Lucia; Trejo-Becerril, Catalina; Duenas-Gonzalez, Alfonso

    2017-03-01

    The aim of the present study was to investigate in vivo the feasibility and efficacy of the combination of lonidamine (LND), 6-diazo-5-oxo-L-norleucine (DON) and orlistat to simultaneously target glycolysis, glutaminolysis and de novo synthesis of fatty acids, respectively. The doses of LND and DON used in humans were translated to mouse doses (77.7 mg/kg and 145.5 mg/kg, respectively) and orlistat was used at 240 mg/kg. Three schedules of LND, DON and orlistat at different doses were administered by intraperitoneal injection to BALB/c mice in a 21-day cycle (schedule 1: LND, 0.5 mg/day; DON, 0.25 mg/day 1, 5 and 9; orlistat, 240 mg/kg/day; schedule 2: LND, 0.1 mg/day; DON, 0.5 mg/day 1, 5 and 9; orlistat, 240 mg/kg/day; schedule 3: LND, 0.5 mg/day; DON, 0.08 mg/day 1, 5 and 9; orlistat, 360 mg/kg/day) to assess tolerability. To determine the antitumor efficacy, a syngeneic tumor model in BALB/c mice was created using colon cancer CT26.WT cells, and a xenogeneic tumor model was created in nude mice using the human colon cancer SW480 cell line. Mice were treated with schedule 1. Animals were weighed, clinically inspected during the experiment and the tumor volume was measured at day 21. The 3 schedules assessed in the tolerability experiments were well tolerated, as mice maintained their weight and no evident clinical signs of toxicity were observed. Combination treatment with schedule 1 significantly decreased tumor growth in each mouse model. No evident signs of toxicity were observed and mice maintained their weight during treatment. The triple metabolic blockade of the malignant phenotype appears feasible and promising for cancer therapy.

  8. GCS component development cycle

    Science.gov (United States)

    Rodríguez, Jose A.; Macias, Rosa; Molgo, Jordi; Guerra, Dailos; Pi, Marti

    2012-09-01

    The GTC1 is an optical-infrared 10-meter segmented mirror telescope at the ORM observatory in Canary Islands (Spain). First light was at 13/07/2007 and since them it is in the operation phase. The GTC control system (GCS) is a distributed object & component oriented system based on RT-CORBA8 and it is responsible for the management and operation of the telescope, including its instrumentation. GCS has used the Rational Unified process (RUP9) in its development. RUP is an iterative software development process framework. After analysing (use cases) and designing (UML10) any of GCS subsystems, an initial component description of its interface is obtained and from that information a component specification is written. In order to improve the code productivity, GCS has adopted the code generation to transform this component specification into the skeleton of component classes based on a software framework, called Device Component Framework. Using the GCS development tools, based on javadoc and gcc, in only one step, the component is generated, compiled and deployed to be tested for the first time through our GUI inspector. The main advantages of this approach are the following: It reduces the learning curve of new developers and the development error rate, allows a systematic use of design patterns in the development and software reuse, speeds up the deliverables of the software product and massively increase the timescale, design consistency and design quality, and eliminates the future refactoring process required for the code.

  9. 2-component heating systems

    Energy Technology Data Exchange (ETDEWEB)

    Radtke, W

    1987-03-01

    The knowledge accumulated only recently of the damage to buildings and the hazards of formaldehyde, radon and hydrocarbons has been inducing louder calls for ventilation, which, on their part, account for the fact that increasing importance is being attached to the controlled ventilation of buildings. Two-component heating systems provide for fresh air and thermal comfort in one. While the first component uses fresh air blown directly and controllably into the rooms, the second component is similar to the Roman hypocaustic heating systems, meaning that heated outer air is circulating under the floor, thus providing for hot surfaces and thermal comfort. Details concerning the two-component heating system are presented along with systems diagrams, diagrams of the heating system and tables identifying the respective costs. Descriptions are given of the two systems components, the fast heat-up, the two-component made, the change of air, heat recovery and control systems. Comparative evaluations determine the differences between two-component heating systems and other heating systems. Conclusive remarks are dedicated to energy conservation and comparative evaluations of costs. (HWJ).

  10. Crystal structure of 5-{4'-[(2-{2-[2-(2-ammonio-eth-oxy)eth-oxy]eth-oxy}eth-yl)carbamo-yl]-4-meth-oxy-[1,1'-biphen-yl]-3-yl}-3-oxo-1,2,5-thia-diazo-lidin-2-ide 1,1-dioxide: a potential inhibitor of the enzyme protein tyrosine phosphatase 1B (PTP1B).

    Science.gov (United States)

    Ruddraraju, Kasi Viswanatharaju; Hillebrand, Roman; Barnes, Charles L; Gates, Kent S

    2015-04-01

    The title compound, C24H32N4O8S, (I), crystallizes as a zwitterion. The terminal amine N atom of the [(2-{2-[2-(2-ammonio-eth-oxy)eth-oxy]eth-oxy}eth-yl)carbamo-yl] side chain is protonated, while the 1,2,5-thia-diazo-lidin-3-one 1,1-dioxide N atom is deprotonated. The side chain is turned over on itself with an intra-molecular N-H⋯O hydrogen bond. The 1,2,5-thia-diazo-lidin-3-one 1,1-dioxide ring has an envelope conformation with the aryl-substituted N atom as the flap. Its mean plane is inclined by 62.87 (8)° to the aryl ring to which it is attached, while the aryl rings of the biphenyl unit are inclined to one another by 20.81 (8)°. In the crystal, mol-ecules are linked by N-H⋯O and N-H⋯N hydrogen bonds, forming slabs lying parallel to (010). Within the slabs there are C-H⋯O and C-H⋯N hydrogen bonds and C-H⋯π inter-actions present.

  11. Replaceable LMFBR core components

    International Nuclear Information System (INIS)

    Evans, E.A.; Cunningham, G.W.

    1976-01-01

    Much progress has been made in understanding material and component performance in the high temperature, fast neutron environment of the LMFBR. Current data have provided strong assurance that the initial core component lifetime objectives of FFTF and CRBR can be met. At the same time, this knowledge translates directly into the need for improved core designs that utilize improved materials and advanced fuels required to meet objectives of low doubling times and extended core component lifetimes. An industrial base for the manufacture of quality core components has been developed in the US, and all procurements for the first two core equivalents for FFTF will be completed this year. However, the problem of fabricating recycled plutonium while dramatically reducing fabrication costs, minimizing personnel exposure, and protecting public health and safety must be addressed

  12. Explosive Components Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The 98,000 square foot Explosive Components Facility (ECF) is a state-of-the-art facility that provides a full-range of chemical, material, and performance analysis...

  13. Component fragility research program

    International Nuclear Information System (INIS)

    Tsai, N.C.; Mochizuki, G.L.; Holman, G.S.

    1989-11-01

    To demonstrate how ''high-level'' qualification test data can be used to estimate the ultimate seismic capacity of nuclear power plant equipment, we assessed in detail various electrical components tested by the Pacific Gas ampersand Electric Company for its Diablo Canyon plant. As part of our Phase I Component Fragility Research Program, we evaluated seismic fragility for five Diablo Canyon components: medium-voltage (4kV) switchgear; safeguard relay board; emergency light battery pack; potential transformer; and station battery and racks. This report discusses our Phase II fragility evaluation of a single Westinghouse Type W motor control center column, a fan cooler motor controller, and three local starters at the Diablo Canyon nuclear power plant. These components were seismically qualified by means of biaxial random motion tests on a shaker table, and the test response spectra formed the basis for the estimate of the seismic capacity of the components. The seismic capacity of each component is referenced to the zero period acceleration (ZPA) and, in our Phase II study only, to the average spectral acceleration (ASA) of the motion at its base. For the motor control center, the seismic capacity was compared to the capacity of a Westinghouse Five-Star MCC subjected to actual fragility tests by LLNL during the Phase I Component Fragility Research Program, and to generic capacities developed by the Brookhaven National Laboratory for motor control center. Except for the medium-voltage switchgear, all of the components considered in both our Phase I and Phase II evaluations were qualified in their standard commercial configurations or with only relatively minor modifications such as top bracing of cabinets. 8 refs., 67 figs., 7 tabs

  14. Refractory alloy component fabrication

    International Nuclear Information System (INIS)

    Young, W.R.

    1984-01-01

    Purpose of this report is to describe joining procedures, primarily welding techniques, which were developed to construct reliable refractory alloy components and systems for advanced space power systems. Two systems, the Nb-1Zr Brayton Cycle Heat Receiver and the T-111 Alloy Potassium Boiler Development Program, are used to illustrate typical systems and components. Particular emphasis is given to specific problems which were eliminated during the development efforts. Finally, some thoughts on application of more recent joining technology are presented. 78 figures

  15. Impact test of components

    International Nuclear Information System (INIS)

    Borsoi, L.; Buland, P.; Labbe, P.

    1987-01-01

    Stops with gaps are currently used to support components and piping: it is simple, low cost, efficient and permits free thermal expansion. In order to keep the nonlinear nature of stops, such design is often modeled by beam elements (for the component) and nonlinear springs (for the stops). This paper deals with the validity and the limits of these models through the comparison of computational and experimental results. The experimental results come from impact laboratory tests on a simplified mockup. (orig.)

  16. Multiscale principal component analysis

    International Nuclear Information System (INIS)

    Akinduko, A A; Gorban, A N

    2014-01-01

    Principal component analysis (PCA) is an important tool in exploring data. The conventional approach to PCA leads to a solution which favours the structures with large variances. This is sensitive to outliers and could obfuscate interesting underlying structures. One of the equivalent definitions of PCA is that it seeks the subspaces that maximize the sum of squared pairwise distances between data projections. This definition opens up more flexibility in the analysis of principal components which is useful in enhancing PCA. In this paper we introduce scales into PCA by maximizing only the sum of pairwise distances between projections for pairs of datapoints with distances within a chosen interval of values [l,u]. The resulting principal component decompositions in Multiscale PCA depend on point (l,u) on the plane and for each point we define projectors onto principal components. Cluster analysis of these projectors reveals the structures in the data at various scales. Each structure is described by the eigenvectors at the medoid point of the cluster which represent the structure. We also use the distortion of projections as a criterion for choosing an appropriate scale especially for data with outliers. This method was tested on both artificial distribution of data and real data. For data with multiscale structures, the method was able to reveal the different structures of the data and also to reduce the effect of outliers in the principal component analysis

  17. Optical CDMA components requirements

    Science.gov (United States)

    Chan, James K.

    1998-08-01

    Optical CDMA is a complementary multiple access technology to WDMA. Optical CDMA potentially provides a large number of virtual optical channels for IXC, LEC and CLEC or supports a large number of high-speed users in LAN. In a network, it provides asynchronous, multi-rate, multi-user communication with network scalability, re-configurability (bandwidth on demand), and network security (provided by inherent CDMA coding). However, optical CDMA technology is less mature in comparison to WDMA. The components requirements are also different from WDMA. We have demonstrated a video transport/switching system over a distance of 40 Km using discrete optical components in our laboratory. We are currently pursuing PIC implementation. In this paper, we will describe the optical CDMA concept/features, the demonstration system, and the requirements of some critical optical components such as broadband optical source, broadband optical amplifier, spectral spreading/de- spreading, and fixed/programmable mask.

  18. Solid state lighting component

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Thomas; Keller, Bernd; Tarsa, Eric; Ibbetson, James; Morgan, Frederick; Dowling, Kevin; Lys, Ihor

    2017-10-17

    An LED component according to the present invention comprising an array of LED chips mounted on a submount with the LED chips capable of emitting light in response to an electrical signal. The array can comprise LED chips emitting at two colors of light wherein the LED component emits light comprising the combination of the two colors of light. A single lens is included over the array of LED chips. The LED chip array can emit light of greater than 800 lumens with a drive current of less than 150 milli-Amps. The LED chip component can also operate at temperatures less than 3000 degrees K. In one embodiment, the LED array is in a substantially circular pattern on the submount.

  19. An integrated magnetics component

    DEFF Research Database (Denmark)

    2013-01-01

    The present invention relates to an integrated magnetics component comprising a magnetically permeable core comprising a base member extending in a horizontal plane and first, second, third and fourth legs protruding substantially perpendicularly from the base member. First, second, third...... and fourth output inductor windings are wound around the first, second, third and fourth legs, respectively. A first input conductor of the integrated magnetics component has a first conductor axis and extends in-between the first, second, third and fourth legs to induce a first magnetic flux through a first...... flux path of the magnetically permeable core. A second input conductor of the integrated magnetics component has a second coil axis extending substantially perpendicularly to the first conductor axis to induce a second magnetic flux through a second flux path of the magnetically permeable core...

  20. Cognitive Component Analysis

    DEFF Research Database (Denmark)

    Feng, Ling

    2008-01-01

    This dissertation concerns the investigation of the consistency of statistical regularities in a signaling ecology and human cognition, while inferring appropriate actions for a speech-based perceptual task. It is based on unsupervised Independent Component Analysis providing a rich spectrum...... of audio contexts along with pattern recognition methods to map components to known contexts. It also involves looking for the right representations for auditory inputs, i.e. the data analytic processing pipelines invoked by human brains. The main ideas refer to Cognitive Component Analysis, defined...... as the process of unsupervised grouping of generic data such that the ensuing group structure is well-aligned with that resulting from human cognitive activity. Its hypothesis runs ecologically: features which are essentially independent in a context defined ensemble, can be efficiently coded as sparse...

  1. Electronic components and systems

    CERN Document Server

    Dennis, W H

    2013-01-01

    Electronic Components and Systems focuses on the principles and processes in the field of electronics and the integrated circuit. Covered in the book are basic aspects and physical fundamentals; different types of materials involved in the field; and passive and active electronic components such as capacitors, inductors, diodes, and transistors. Also covered in the book are topics such as the fabrication of semiconductors and integrated circuits; analog circuitry; digital logic technology; and microprocessors. The monograph is recommended for beginning electrical engineers who would like to kn

  2. Validating Timed Component Contracts

    DEFF Research Database (Denmark)

    Le Guilly, Thibaut; Liu, Shaoying; Olsen, Petur

    2015-01-01

    This paper presents a technique for testing software components with contracts that specify functional behavior, synchronization, as well as timing behavior. The approach combines elements from unit testing with model-based testing techniques for timed automata. The technique is implemented...... in an online testing tool, and we demonstrate its use on a concrete use case....

  3. Euler principal component analysis

    NARCIS (Netherlands)

    Liwicki, Stephan; Tzimiropoulos, Georgios; Zafeiriou, Stefanos; Pantic, Maja

    Principal Component Analysis (PCA) is perhaps the most prominent learning tool for dimensionality reduction in pattern recognition and computer vision. However, the ℓ 2-norm employed by standard PCA is not robust to outliers. In this paper, we propose a kernel PCA method for fast and robust PCA,

  4. Hybrid wars’ information component

    Directory of Open Access Journals (Sweden)

    T. A. Nevskaya

    2015-01-01

    Full Text Available The war of the new generation - hybrid war, the information component which is directed not so much on the direct destruction of the enemy, how to achieve the goals without warfare. Fighting in the information field is no less important than immediate military action.

  5. ITER plasma facing components

    International Nuclear Information System (INIS)

    Kuroda, T.; Vieider, G.; Akiba, M.

    1991-01-01

    This document summarizes results of the Conceptual Design Activities (1988-1990) for the International Thermonuclear Experimental Reactor (ITER) project, namely those that pertain to the plasma facing components of the reactor vessel, of which the main components are the first wall and the divertor plates. After an introduction and an executive summary, the principal functions of the plasma-facing components are delineated, i.e., (i) define the low-impurity region within which the plasma is produced, (ii) absorb the electromagnetic radiation and charged-particle flux from the plasma, and (iii) protect the blanket/shield components from the plasma. A list of critical design issues for the divertor plates and the first wall is given, followed by discussions of the divertor plate design (including the issues of material selection, erosion lifetime, design concepts, thermal and mechanical analysis, operating limits and overall lifetime, tritium inventory, baking and conditioning, safety analysis, manufacture and testing, and advanced divertor concepts) and the first wall design (armor material and design, erosion lifetime, overall design concepts, thermal and mechanical analysis, lifetime and operating limits, tritium inventory, baking and conditioning, safety analysis, manufacture and testing, an alternative first wall design, and the limiters used instead of the divertor plates during start-up). Refs, figs and tabs

  6. Spain's nuclear components industry

    International Nuclear Information System (INIS)

    Kaibel, E.

    1985-01-01

    Spanish industrial participation in supply of components for nuclear power plants has grown steadily over the last fifteen years. The share of Spanish companies in work for the five second generation nuclear power plants increased to 50% of total capital investments. The necessity to maintain Spanish technology and production in the nuclear field is emphasized

  7. The market for components

    International Nuclear Information System (INIS)

    Simon, M.; Stoelzl, D.

    1986-01-01

    The offers of the German nuclear components industry are shown at the examples of some masterpieces of engineering and their delivery capacities. Then, the success achieved with exports up to now are referred to. The forecast includes the demand, the side conditions of the technical competition, and the pricing and financing situation. (UA) [de

  8. Bayesian Independent Component Analysis

    DEFF Research Database (Denmark)

    Winther, Ole; Petersen, Kaare Brandt

    2007-01-01

    In this paper we present an empirical Bayesian framework for independent component analysis. The framework provides estimates of the sources, the mixing matrix and the noise parameters, and is flexible with respect to choice of source prior and the number of sources and sensors. Inside the engine...

  9. Component-oriented programming

    NARCIS (Netherlands)

    Bosch, J; Szyperski, C; Weck, W; Buschmann, F; Buchmann, AP; Cilia, MA

    2003-01-01

    This report covers the eighth Workshop on Component-Oriented Programming (WCOP). WCOP has been affiliated with ECOOP since its inception in 1996. The report summarizes the contributions made by authors of accepted position papers as well as those made by all attendees of the workshop sessions.

  10. Developing a Model Component

    Science.gov (United States)

    Fields, Christina M.

    2013-01-01

    The Spaceport Command and Control System (SCCS) Simulation Computer Software Configuration Item (CSCI) is responsible for providing simulations to support test and verification of SCCS hardware and software. The Universal Coolant Transporter System (UCTS) was a Space Shuttle Orbiter support piece of the Ground Servicing Equipment (GSE). The initial purpose of the UCTS was to provide two support services to the Space Shuttle Orbiter immediately after landing at the Shuttle Landing Facility. The UCTS is designed with the capability of servicing future space vehicles; including all Space Station Requirements necessary for the MPLM Modules. The Simulation uses GSE Models to stand in for the actual systems to support testing of SCCS systems during their development. As an intern at Kennedy Space Center (KSC), my assignment was to develop a model component for the UCTS. I was given a fluid component (dryer) to model in Simulink. I completed training for UNIX and Simulink. The dryer is a Catch All replaceable core type filter-dryer. The filter-dryer provides maximum protection for the thermostatic expansion valve and solenoid valve from dirt that may be in the system. The filter-dryer also protects the valves from freezing up. I researched fluid dynamics to understand the function of my component. The filter-dryer was modeled by determining affects it has on the pressure and velocity of the system. I used Bernoulli's Equation to calculate the pressure and velocity differential through the dryer. I created my filter-dryer model in Simulink and wrote the test script to test the component. I completed component testing and captured test data. The finalized model was sent for peer review for any improvements. I participated in Simulation meetings and was involved in the subsystem design process and team collaborations. I gained valuable work experience and insight into a career path as an engineer.

  11. Adaptable component frameworks

    DEFF Research Database (Denmark)

    Katajainen, Jyrki; Simonsen, Bo

    2009-01-01

    The CPH STL is a special edition of the STL, the containers and algorithms part of the C++ standard library. The specification of the generic components of the STL is given in the C++ standard. Any implementation of the STL, e.g. the one that ships with your standard-compliant C++ compiler, should...... for vector, which is undoubtedly the most used container of the C++ standard library. In particular, we specify the details of a vector implementation that is safe with respect to referential integrity and strong exception safety. Additionally, we report the experiences and lessons learnt from...... the development of component frameworks which we hope to be of benefit to persons engaged in the design and implementation of generic software libraries....

  12. Components of laboratory accreditation.

    Science.gov (United States)

    Royal, P D

    1995-12-01

    Accreditation or certification is a recognition given to an operation or product that has been evaluated against a standard; be it regulatory or voluntary. The purpose of accreditation is to provide the consumer with a level of confidence in the quality of operation (process) and the product of an organization. Environmental Protection Agency/OCM has proposed the development of an accreditation program under National Environmental Laboratory Accreditation Program for Good Laboratory Practice (GLP) laboratories as a supplement to the current program. This proposal was the result of the Inspector General Office reports that identified weaknesses in the current operation. Several accreditation programs can be evaluated and common components identified when proposing a structure for accrediting a GLP system. An understanding of these components is useful in building that structure. Internationally accepted accreditation programs provide a template for building a U.S. GLP accreditation program. This presentation will discuss the traditional structure of accreditation as presented in the Organization of Economic Cooperative Development/GLP program, ISO-9000 Accreditation and ISO/IEC Guide 25 Standard, and the Canadian Association for Environmental Analytical Laboratories, which has a biological component. Most accreditation programs are managed by a recognized third party, either privately or with government oversight. Common components often include a formal review of required credentials to evaluate organizational structure, a site visit to evaluate the facility, and a performance evaluation to assess technical competence. Laboratory performance is measured against written standards and scored. A formal report is then sent to the laboratory indicating accreditation status. Usually, there is a scheduled reevaluation built into the program. Fee structures vary considerably and will need to be examined closely when building a GLP program.

  13. Fabricating nuclear components

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    Activities of the Nuclear Engineering Division of Vickers Ltd., particularly fabrication of long slim tubular components for power reactors and the construction of irradiation loops and rigs, are outlined. The processes include hydraulic forming for fabrication of various types of tubes and outer cases of fuel transfer buckets, various specialised welding operations including some applications of the TIG process, and induction brazing of specialised assemblies. (U.K.)

  14. Components of the environment

    International Nuclear Information System (INIS)

    Klinda, J.; Lieskovska, Z.

    1998-01-01

    This report of the Ministry of the Environment of the Slovak Republic deals with the components of the environment. The results of monitoring of air (emission situation), ambient air quality, atmospheric precipitation, tropospheric ozone, water (surface water, groundwater resources, waste water and drinking water), geological factors (geothermal energy, fuel deposits, ore deposits, non-metallic ore deposits), soil (area statistics, soil contamination. soil reaction and active extractable aluminium, soil erosion), flora and fauna (national strategy of biodiversity protection) are presented

  15. Ionitriding of Weapon Components

    Science.gov (United States)

    1974-01-01

    and documented tho production sequences required for the case- hardening of AISI 4140 and Nitralloy 13514 steels. Determination of processina...depths were established experimentally for Nitralloy 135M and for AISI 4140 steels. These steels are commonly used for the manufacture of nitrlded...weapons components. A temperature of 050F, upper limit for lonitrlding, was selected for the Nitralloy 135M to keep treatment times short. Since AISI 4140

  16. Components of QCD

    International Nuclear Information System (INIS)

    Sivers, D.

    1979-10-01

    Some aspects of a simple strategy for testing the validity of QCD perturbation theory are examined. The importance of explicit evaluation of higher-order contributions is illustrated by considering Z 0 decays. The recent progress toward understanding exclusive processes in QCD is discussed and some simple examples are given of how to isolate and test the separate components of the perturbation expansion in a hypothetical series of jet experiments

  17. Optimized Kernel Entropy Components.

    Science.gov (United States)

    Izquierdo-Verdiguier, Emma; Laparra, Valero; Jenssen, Robert; Gomez-Chova, Luis; Camps-Valls, Gustau

    2017-06-01

    This brief addresses two main issues of the standard kernel entropy component analysis (KECA) algorithm: the optimization of the kernel decomposition and the optimization of the Gaussian kernel parameter. KECA roughly reduces to a sorting of the importance of kernel eigenvectors by entropy instead of variance, as in the kernel principal components analysis. In this brief, we propose an extension of the KECA method, named optimized KECA (OKECA), that directly extracts the optimal features retaining most of the data entropy by means of compacting the information in very few features (often in just one or two). The proposed method produces features which have higher expressive power. In particular, it is based on the independent component analysis framework, and introduces an extra rotation to the eigen decomposition, which is optimized via gradient-ascent search. This maximum entropy preservation suggests that OKECA features are more efficient than KECA features for density estimation. In addition, a critical issue in both the methods is the selection of the kernel parameter, since it critically affects the resulting performance. Here, we analyze the most common kernel length-scale selection criteria. The results of both the methods are illustrated in different synthetic and real problems. Results show that OKECA returns projections with more expressive power than KECA, the most successful rule for estimating the kernel parameter is based on maximum likelihood, and OKECA is more robust to the selection of the length-scale parameter in kernel density estimation.

  18. Reinforced seal component

    International Nuclear Information System (INIS)

    Jeanson, G.M.; Odent, R.P.

    1980-01-01

    The invention concerns a seal component of the kind comprising a soft sheath and a flexible reinforcement housed throughout the entire length of the sheath. The invention enables O ring seals to be made capable of providing a radial seal, that is to say between two sides or flat collars of two cylindrical mechanical parts, or an axial seal, that is to say between two co-axial axisymmetrical areas. The seal so ensured is relative, but it remains adequately sufficient for many uses, for instance, to ensure the separation of two successive fixed blading compartments of axial compressors used in gas diffusion isotope concentration facilities [fr

  19. Electronic components and technology

    CERN Document Server

    Sangwine, Stephen

    2007-01-01

    Most introductory textbooks in electronics focus on the theory while leaving the practical aspects to be covered in laboratory courses. However, the sooner such matters are introduced, the better able students will be to include such important concerns as parasitic effects and reliability at the very earliest stages of design. This philosophy has kept Electronic Components and Technology thriving for two decades, and this completely updated third edition continues the approach with a more international outlook.Not only does this textbook introduce the properties, behavior, fabrication, and use

  20. Autonomous component carrier selection

    DEFF Research Database (Denmark)

    Garcia, Luis Guilherme Uzeda; Pedersen, Klaus; Mogensen, Preben

    2009-01-01

    management and efficient system operation. Due to the expected large number of user-deployed cells, centralized network planning becomes unpractical and new scalable alternatives must be sought. In this article, we propose a fully distributed and scalable solution to the interference management problem...... in local areas, basing our study case on LTE-Advanced. We present extensive network simulation results to demonstrate that a simple and robust interference management scheme, called autonomous component carrier selection allows each cell to select the most attractive frequency configuration; improving...... the experience of all users and not just the few best ones; while overall cell capacity is not compromised....

  1. Impedance of accelerator components

    International Nuclear Information System (INIS)

    Corlett, J.N.

    1996-05-01

    As demands for high luminosity and low emittance particle beams increase, an understanding of the electromagnetic interaction of these beams with their vacuum chamber environment becomes more important in order to maintain the quality of the beam. This interaction is described in terms of the wake field in time domain, and the beam impedance in frequency domain. These concepts are introduced, and related quantities such as the loss factor are presented. The broadband Q = 1 resonator impedance model is discussed. Perturbation and coaxial wire methods of measurement of real components are reviewed

  2. Z-Selective iridium-catalyzed cross-coupling of allylic carbonates and α-diazo esters† †Electronic supplementary information (ESI) available: Full procedures, computational details and characterization data. See DOI: 10.1039/c7sc04283c

    Science.gov (United States)

    Thomas, Bryce N.; Moon, Patrick J.; Yin, Shengkang; Brown, Alex

    2017-01-01

    A well-defined Ir–allyl complex catalyzes the Z-selective cross-coupling of allyl carbonates with α-aryl diazo esters. The process overrides the large thermodynamic preference for E-products typically observed in metal-mediated coupling reactions to enable the synthesis of Z,E-dieneoates in good yield with selectivities consistently approaching or greater than 90 : 10. This transformation represents the first productive merger of Ir–carbene and Ir–allyl species, which are commonly encountered intermediates in allylation and cyclopropanation/E–H insertion catalysis. Potentially reactive functional groups (aryl halides, ketones, nitriles, olefins, amines) are tolerated owing to the mildness of reaction conditions. Kinetic analysis of the reaction suggests oxidative addition of the allyl carbonate to an Ir-species is rate-determining. Mechanistic studies uncovered a pathway for catalyst activation mediated by NEt3. PMID:29629093

  3. Interactions between photodegradation components

    Directory of Open Access Journals (Sweden)

    Abdollahi Yadollah

    2012-09-01

    Full Text Available Abstract Background The interactions of p-cresol photocatalytic degradation components were studied by response surface methodology. The study was designed by central composite design using the irradiation time, pH, the amount of photocatalyst and the p-cresol concentration as variables. The design was performed to obtain photodegradation % as actual responses. The actual responses were fitted with linear, two factor interactions, cubic and quadratic model to select an appropriate model. The selected model was validated by analysis of variance which provided evidences such as high F-value (845.09, very low P-value (2 = 0.999, adjusted R-squared (Radj2 = 0.998, predicted R-squared (Rpred2 = 0.994 and the adequate precision (95.94. Results From the validated model demonstrated that the component had interaction with irradiation time under 180 min of the time while the interaction with pH was above pH 9. Moreover, photocatalyst and p-cresol had interaction at minimal amount of photocatalyst (p-cresol. Conclusion These variables are interdependent and should be simultaneously considered during the photodegradation process, which is one of the advantages of the response surface methodology over the traditional laboratory method.

  4. Prognostics for Microgrid Components

    Science.gov (United States)

    Saxena, Abhinav

    2012-01-01

    Prognostics is the science of predicting future performance and potential failures based on targeted condition monitoring. Moving away from the traditional reliability centric view, prognostics aims at detecting and quantifying the time to impending failures. This advance warning provides the opportunity to take actions that can preserve uptime, reduce cost of damage, or extend the life of the component. The talk will focus on the concepts and basics of prognostics from the viewpoint of condition-based systems health management. Differences with other techniques used in systems health management and philosophies of prognostics used in other domains will be shown. Examples relevant to micro grid systems and subsystems will be used to illustrate various types of prediction scenarios and the resources it take to set up a desired prognostic system. Specifically, the implementation results for power storage and power semiconductor components will demonstrate specific solution approaches of prognostics. The role of constituent elements of prognostics, such as model, prediction algorithms, failure threshold, run-to-failure data, requirements and specifications, and post-prognostic reasoning will be explained. A discussion on performance evaluation and performance metrics will conclude the technical discussion followed by general comments on open research problems and challenges in prognostics.

  5. Synthesis and vibrational spectra of cooper(II) and erbium(III) complexes with 2-diazo[2'-(oxymethyldiphenylphosphinyl)phenyl]-4-tert-butylphenol (HL) - [CuL2]·2H2O and Er(NO3)3·2HL·2H2O. Crystal structure of [CuL2]·2H2O

    International Nuclear Information System (INIS)

    Tsivadze, A.Yu.; Minacheva, L.Kh.; Ivanova, I.S.; Pyatova, E.N.; Sergienko, V.S.; Baulin, V.E.

    2008-01-01

    Paper describes synthesis of CuL 2 ·2H 2 O (I) complex cupric salt and of Er(NO 3 ) 3 ·2HL·2H 2 O (II) erbium nitrate complex (HL=2-diazo-[2'(oxymethyl-diphenyl-phosphinyl)phenyl]-4-tert-butylphenol). One interprets the fundamental frequencies within the IR-spectra of (I) and (II) compounds. One has performed X-ray diffraction analysis of I compound. The crystals are monoclinic ones, a=15.157(3), b=17.080(2), c=22.451(9) A, β=106.09(3) Deg, V=5584(3) A 3 , Z=4, C2/c sp.gr., R=0.0546 as to 1152 reflections with I>2σ(I). The copper atom coordination polyhedron (C 2 symmetry) may be described as a symmetrically-prolonged square bipyramid (4+2). Cu polyhedron central square is formed by substituted phenol oxygen atom and by one of diazo-group nitrogen atoms of either of two deprotonated ligands, namely: L - (Cu-N 1.969(6), Cu-O 1.899(5) A). The angles between lying opposite O and N atoms constitute 157.6 Deg, while the rest equatorial angles range within 90.6 Deg-95.9 Deg. The axial positions are occupied by O(2) and O(2A) anisole atoms (Cu-O 2.737(6) A, O(2)Cu(1)O(2A) angle constitutes 132.3 Deg). Within crystal I the complex molecules and the crystallization molecules of water are combined by by the hydrogen bond system. According to the IR-spectra data, within complex II in contrast to compound I erbium atom coordination by HL ligand involves oxygen phosphoryl atom [ru

  6. Food Components and Supplements

    DEFF Research Database (Denmark)

    Parlesak, Alexandr

    2012-01-01

    The major part of food consists of chemical compounds that can be used for energy production, biological synthesis, or maintenance of metabolic processes by the host. These components are defined as nutrients, and can be categorized into macronutrients (proteins, carbohydrates, triglycerides......, and alcohol), minerals, and micronutrients. The latter category comprises 13 vitamins and a hand full of trace elements. Many micronutrients are used as food supplements and are ingested at doses exceeding the amounts that can be consumed along with food by a factor of 10–100. Both macro- and micronutrients...... can interact with enzyme systems related to xenobiotic metabolism either by regulation of their expression or direct interference with their enzymatic activity. During food consumption, we consume a wide range of xenobiotics along with the consumable food, either as an original part of the food (e...

  7. Sprayed skin turbine component

    Science.gov (United States)

    Allen, David B

    2013-06-04

    Fabricating a turbine component (50) by casting a core structure (30), forming an array of pits (24) in an outer surface (32) of the core structure, depositing a transient liquid phase (TLP) material (40) on the outer surface of the core structure, the TLP containing a melting-point depressant, depositing a skin (42) on the outer surface of the core structure over the TLP material, and heating the assembly, thus forming both a diffusion bond and a mechanical interlock between the skin and the core structure. The heating diffuses the melting-point depressant away from the interface. Subsurface cooling channels (35) may be formed by forming grooves (34) in the outer surface of the core structure, filling the grooves with a fugitive filler (36), depositing and bonding the skin (42), then removing the fugitive material.

  8. Food Components and Supplements

    DEFF Research Database (Denmark)

    Parlesak, Alexandr

    2012-01-01

    acting as carcinogens) to health-protective effects (e.g., flavonoids ameliorating detrimental effects of mitochondrial oxidative stress). In particular, secondary plant metabolites along with vitamins, specific types of macronutrients and live bacteria (probiotics) as well as substances promoting.......g., secondary plant metabolites such as flavonoids), or as contaminants that enter the food chain at different stages or during the food production process. For these components, a wide spectrum of biological effects was observed that ranges from health-threatening impacts (e.g., polycyclic aromatic amines....... The supplements and contaminants can compete directly with drug oxidation, induce or suppress the expression of xenobiotic-metabolizing enzymes, change the bioavailability of drugs, and, in the case of live bacteria, bring in their own xenobiotic metabolism, including cytochrome P450 (CYP) activity. In numerous...

  9. Component failure data handbook

    International Nuclear Information System (INIS)

    Gentillon, C.D.

    1991-04-01

    This report presents generic component failure rates that are used in reliability and risk studies of commercial nuclear power plants. The rates are computed using plant-specific data from published probabilistic risk assessments supplemented by selected other sources. Each data source is described. For rates with four or more separate estimates among the sources, plots show the data that are combined. The method for combining data from different sources is presented. The resulting aggregated rates are listed with upper bounds that reflect the variability observed in each rate across the nuclear power plant industry. Thus, the rates are generic. Both per hour and per demand rates are included. They may be used for screening in risk assessments or for forming distributions to be updated with plant-specific data

  10. High thermal load component

    International Nuclear Information System (INIS)

    Fuse, Toshiaki; Tachikawa, Nobuo.

    1996-01-01

    A cooling tube made of a pure copper is connected to the inner portion of an armour (heat resistant member) made of an anisotropic carbon/carbon composite (CFC) material. The CFC material has a high heat conductivity in longitudinal direction of fibers and has low conductivity in perpendicular thereto. Fibers extending in the armour from a heat receiving surface just above the cooling tube are directly connected to the cooling tube. A portion of the fibers extending from a heat receiving surface other than portions not just above the cooling tube is directly bonded to the cooling tube. Remaining fibers are disposed so as to surround the cooling tube. The armour and the cooling tube are soldered using an active metal flux. With such procedures, high thermal load components for use in a thermonuclear reactor are formed, which are excellent in a heat removing characteristic and hardly causes defects such as crackings and peeling. (I.N.)

  11. Impedance and component heating

    CERN Document Server

    Métral, E; Mounet, N; Pieloni, T; Salvant, B

    2015-01-01

    The impedance is a complex function of frequency, which represents, for the plane under consideration (longitudinal, horizontal or vertical), the force integrated over the length of an element, from a “source” to a “test” wave, normalized by their charges. In general, the impedance in a given plane is a nonlinear function of the test and source transverse coordinates, but it is most of the time sufficient to consider only the first few linear terms. Impedances can influence the motion of trailing particles, in the longitudinal and in one or both transverse directions, leading to energy loss, beam instabilities, or producing undesirable secondary effects such as excessive heating of sensitive components at or near the chamber wall, called beam-induced RF heating. The LHC performance limitations linked to impedances encountered during the 2010-2012 run are reviewed and the currently expected situation during the HL-LHC era is discussed.

  12. Initial Ada components evaluation

    Science.gov (United States)

    Moebes, Travis

    1989-01-01

    The SAIC has the responsibility for independent test and validation of the SSE. They have been using a mathematical functions library package implemented in Ada to test the SSE IV and V process. The library package consists of elementary mathematical functions and is both machine and accuracy independent. The SSE Ada components evaluation includes code complexity metrics based on Halstead's software science metrics and McCabe's measure of cyclomatic complexity. Halstead's metrics are based on the number of operators and operands on a logical unit of code and are compiled from the number of distinct operators, distinct operands, and total number of occurrences of operators and operands. These metrics give an indication of the physical size of a program in terms of operators and operands and are used diagnostically to point to potential problems. McCabe's Cyclomatic Complexity Metrics (CCM) are compiled from flow charts transformed to equivalent directed graphs. The CCM is a measure of the total number of linearly independent paths through the code's control structure. These metrics were computed for the Ada mathematical functions library using Software Automated Verification and Validation (SAVVAS), the SSE IV and V tool. A table with selected results was shown, indicating that most of these routines are of good quality. Thresholds for the Halstead measures indicate poor quality if the length metric exceeds 260 or difficulty is greater than 190. The McCabe CCM indicated a high quality of software products.

  13. Radiation damage in components

    International Nuclear Information System (INIS)

    Takano, Tomehachi

    1977-01-01

    The performance change of typical capacitors and resistors in electronic components by Co-60 γ-irradiation from the 1320 Ci source was examined in the range of 10 5 to 10 8 R. Specifically, the characteristic change during irradiation and the recovery after irradiation were continuously observed. The capacity change is +2.4% at maximum in ceramic and metallized paper capacitors, and -2.4% at maximum in mylar and paper capacitors. It is also +-0.4% at maximum in mica and polystyrene capacitors. Some of these capacitors showed the recovery of the capacity change, but the others did not. Dielectric loss varied by 15% at larger dose in some capacitors, and the recovery was not observed. While, the insulation resistance of the resistors of 10 15 Ω or more lowered to 10 13 Ω or less after 10 to 30 sec. irradiation, but recovered soon nearly to the initial values after irradiation was interrupted. The resistance change of carbon film resistors is about 0.2 to 2%, and recovered to the initial values in 100 hours after irradiation. The resistance change of composition resistors is large over the range of -13 to +35%, besides, no sign of recovery was seen. In carbon film resistors, the surface insulated type indicated far better results which are assumed to be caused by the selection of element materials and the forming of coating materials. (Wakatsuki, Y.)

  14. Component-based development process and component lifecycle

    NARCIS (Netherlands)

    Crnkovic, I.; Chaudron, M.R.V.; Larsson, S.

    2006-01-01

    The process of component- and component-based system development differs in many significant ways from the "classical" development process of software systems. The main difference is in the separation of the development process of components from the development process of systems. This fact has a

  15. GOATS - Orbitology Component

    Science.gov (United States)

    Haber, Benjamin M.; Green, Joseph J.

    2010-01-01

    The GOATS Orbitology Component software was developed to specifically address the concerns presented by orbit analysis tools that are often written as stand-alone applications. These applications do not easily interface with standard JPL first-principles analysis tools, and have a steep learning curve due to their complicated nature. This toolset is written as a series of MATLAB functions, allowing seamless integration into existing JPL optical systems engineering modeling and analysis modules. The functions are completely open, and allow for advanced users to delve into and modify the underlying physics being modeled. Additionally, this software module fills an analysis gap, allowing for quick, high-level mission analysis trades without the need for detailed and complicated orbit analysis using commercial stand-alone tools. This software consists of a series of MATLAB functions to provide for geometric orbit-related analysis. This includes propagation of orbits to varying levels of generalization. In the simplest case, geosynchronous orbits can be modeled by specifying a subset of three orbit elements. The next case is a circular orbit, which can be specified by a subset of four orbit elements. The most general case is an arbitrary elliptical orbit specified by all six orbit elements. These orbits are all solved geometrically, under the basic problem of an object in circular (or elliptical) orbit around a rotating spheroid. The orbit functions output time series ground tracks, which serve as the basis for more detailed orbit analysis. This software module also includes functions to track the positions of the Sun, Moon, and arbitrary celestial bodies specified by right ascension and declination. Also included are functions to calculate line-of-sight geometries to ground-based targets, angular rotations and decompositions, and other line-of-site calculations. The toolset allows for the rapid execution of orbit trade studies at the level of detail required for the

  16. Towards Prognostics for Electronics Components

    Data.gov (United States)

    National Aeronautics and Space Administration — Electronics components have an increasingly critical role in avionics systems and in the development of future aircraft systems. Prognostics of such components is...

  17. Independent component analysis: recent advances

    OpenAIRE

    Hyv?rinen, Aapo

    2013-01-01

    Independent component analysis is a probabilistic method for learning a linear transform of a random vector. The goal is to find components that are maximally independent and non-Gaussian (non-normal). Its fundamental difference to classical multi-variate statistical methods is in the assumption of non-Gaussianity, which enables the identification of original, underlying components, in contrast to classical methods. The basic theory of independent component analysis was mainly developed in th...

  18. Statistics of Shared Components in Complex Component Systems

    Science.gov (United States)

    Mazzolini, Andrea; Gherardi, Marco; Caselle, Michele; Cosentino Lagomarsino, Marco; Osella, Matteo

    2018-04-01

    Many complex systems are modular. Such systems can be represented as "component systems," i.e., sets of elementary components, such as LEGO bricks in LEGO sets. The bricks found in a LEGO set reflect a target architecture, which can be built following a set-specific list of instructions. In other component systems, instead, the underlying functional design and constraints are not obvious a priori, and their detection is often a challenge of both scientific and practical importance, requiring a clear understanding of component statistics. Importantly, some quantitative invariants appear to be common to many component systems, most notably a common broad distribution of component abundances, which often resembles the well-known Zipf's law. Such "laws" affect in a general and nontrivial way the component statistics, potentially hindering the identification of system-specific functional constraints or generative processes. Here, we specifically focus on the statistics of shared components, i.e., the distribution of the number of components shared by different system realizations, such as the common bricks found in different LEGO sets. To account for the effects of component heterogeneity, we consider a simple null model, which builds system realizations by random draws from a universe of possible components. Under general assumptions on abundance heterogeneity, we provide analytical estimates of component occurrence, which quantify exhaustively the statistics of shared components. Surprisingly, this simple null model can positively explain important features of empirical component-occurrence distributions obtained from large-scale data on bacterial genomes, LEGO sets, and book chapters. Specific architectural features and functional constraints can be detected from occurrence patterns as deviations from these null predictions, as we show for the illustrative case of the "core" genome in bacteria.

  19. Statistics of Shared Components in Complex Component Systems

    Directory of Open Access Journals (Sweden)

    Andrea Mazzolini

    2018-04-01

    Full Text Available Many complex systems are modular. Such systems can be represented as “component systems,” i.e., sets of elementary components, such as LEGO bricks in LEGO sets. The bricks found in a LEGO set reflect a target architecture, which can be built following a set-specific list of instructions. In other component systems, instead, the underlying functional design and constraints are not obvious a priori, and their detection is often a challenge of both scientific and practical importance, requiring a clear understanding of component statistics. Importantly, some quantitative invariants appear to be common to many component systems, most notably a common broad distribution of component abundances, which often resembles the well-known Zipf’s law. Such “laws” affect in a general and nontrivial way the component statistics, potentially hindering the identification of system-specific functional constraints or generative processes. Here, we specifically focus on the statistics of shared components, i.e., the distribution of the number of components shared by different system realizations, such as the common bricks found in different LEGO sets. To account for the effects of component heterogeneity, we consider a simple null model, which builds system realizations by random draws from a universe of possible components. Under general assumptions on abundance heterogeneity, we provide analytical estimates of component occurrence, which quantify exhaustively the statistics of shared components. Surprisingly, this simple null model can positively explain important features of empirical component-occurrence distributions obtained from large-scale data on bacterial genomes, LEGO sets, and book chapters. Specific architectural features and functional constraints can be detected from occurrence patterns as deviations from these null predictions, as we show for the illustrative case of the “core” genome in bacteria.

  20. Unblockable Compositions of Software Components

    DEFF Research Database (Denmark)

    Dong, Ruzhen; Faber, Johannes; Liu, Zhiming

    2012-01-01

    We present a new automata-based interface model describing the interaction behavior of software components. Contrary to earlier component- or interface-based approaches, the interface model we propose specifies all the non-blockable interaction behaviors of a component with any environment...... composition of interface models preserves unblockable sequences of provided services....

  1. Component Reification in Systems Modelling

    DEFF Research Database (Denmark)

    Bendisposto, Jens; Hallerstede, Stefan

    When modelling concurrent or distributed systems in Event-B, we often obtain models where the structure of the connected components is specified by constants. Their behaviour is specified by the non-deterministic choice of event parameters for events that operate on shared variables. From a certain......? These components may still refer to shared variables. Events of these components should not refer to the constants specifying the structure. The non-deterministic choice between these components should not be via parameters. We say the components are reified. We need to address how the reified components get...... reflected into the original model. This reflection should indicate the constraints on how to connect the components....

  2. Component Composition Using Feature Models

    DEFF Research Database (Denmark)

    Eichberg, Michael; Klose, Karl; Mitschke, Ralf

    2010-01-01

    interface description languages. If this variability is relevant when selecting a matching component then human interaction is required to decide which components can be bound. We propose to use feature models for making this variability explicit and (re-)enabling automatic component binding. In our...... approach, feature models are one part of service specifications. This enables to declaratively specify which service variant is provided by a component. By referring to a service's variation points, a component that requires a specific service can list the requirements on the desired variant. Using...... these specifications, a component environment can then determine if a binding of the components exists that satisfies all requirements. The prototypical environment Columbus demonstrates the feasibility of the approach....

  3. Investigation in field of diazo compounds

    International Nuclear Information System (INIS)

    Eremin, S.K.; Kozlov, V.V.

    1976-01-01

    Interaction of para-substituted borofluorides of phenyldiazonium with anion-active resins in OH-form has been studied by UV spectroscopy. It is shown for p-nitrophenyldiazonium that in solutions with excess of ion-exchange resin an ion exchange takes place with fixation on the resin of a diazotate anion and of another particle capable of combining (probably diazoanhydride). An excess of the diazocompound gives rise to diazoaminocompound

  4. Investigations in the field of diazo compounds

    International Nuclear Information System (INIS)

    Kozlov, V.V.; Smirnova, V.G.; Sagalovich, V.P.

    1977-01-01

    Water suspension of hardly soluble isopolytungstates and -molybdates of diazonium have been decomposed. It has been established that the corresponding phenols are the main reaction products with the yield of 69.6-84.5%. Kinetics of thermal decomposition of phenyldiazonium fluoroborate (1) has been studied at 40+-0.1 deg C in 0.01 and 0.1 N H 2 O 4 in the presence of para(hepta)molybdate of ammonium (2). Decomposition of (1) in 0.1 N H 2 O 4 in the presence of (2) obeys the equation of the first order reaction up to the concentration of (2), equal to 0.250. Kinetic experiments have shown that a maximum decrease of the rate constant of decomposition of (1) in an acid aqueous solution in the presence of meta(octa) molybdate of sodium does not exceed 18%. Interaction of phenyldiazonium chloride with para(hepta) molybdate of ammonium gives meta(octa) molybdate of phenyldiazonium. Kinetic experiments do not confirm a considerable stabilizing effect of isopolymolybdates on diazosolutions

  5. SBA Network Components & Software Inventory

    Data.gov (United States)

    Small Business Administration — SBA’s Network Components & Software Inventory contains a complete inventory of all devices connected to SBA’s network including workstations, servers, routers,...

  6. Components selection for ageing management

    International Nuclear Information System (INIS)

    Mingiuc, C.; Vidican, D.

    2002-01-01

    Full text: The paper presents a synthesis of methods and activities realized for the selection of critical components to assure plant safety and availability (as electricity supplier). There are presented main criteria for selection, screening process. For the resulted categories of components shall be applied different category of maintenance (condition oriented, scheduled or corrective), function of the importance and financial effort necessary to fulfil the task. 1. Systems and components screening for plant safety assurance For the systems selection, from Safety point of view, was necessary first, to define systems which are dangerous in case of failure (mainly by rupture/ release of radioactivity) and the safety systems which have to mitigate the effects. This is realized based on accident analysis (from Safety Report). Also where taken in to account the 4 basic Safety Principles: 'Reactor shut down; Residual heat removal; Radioactivity products confinement; NPP status monitoring in normal and accident conditions'. Following step is to establish safety support systems, which have to action to assure main safety systems operation. This could be realized based on engineering judgement, or on PSA Level I analysis. Finally shall be realized chains of the support systems, which have to work, till primary systems. For the critical components selection, was realized a Failure Mode and Effect Analysis (FMEA), considering the components effects of failures, on system safety function. 2. Systems and components screening for plant availability assurance The work was realized in two steps: Systems screening; Components screening The systems screening, included: General, analyze of the plant systems list and the definition of those which clearly have to run continue to assure the nominal power; Realization of a complex diagram to define interdependence between the systems (e.g. PHT and auxiliaries, moderator and auxiliaries, plant electrical diagram); Fill of special

  7. APS beamline standard components handbook

    International Nuclear Information System (INIS)

    Kuzay, T.M.

    1992-01-01

    It is clear that most Advanced Photon Source (APS) Collaborative Access Team (CAT) members would like to concentrate on designing specialized equipment related to their scientific programs rather than on routine or standard beamline components. Thus, an effort is in progress at the APS to identify standard and modular components of APS beamlines. Identifying standard components is a nontrivial task because these components should support diverse beamline objectives. To assist with this effort, the APS has obtained advice and help from a Beamline Standardization and Modularization Committee consisting of experts in beamline design, construction, and operation. The staff of the Experimental Facilities Division identified various components thought to be standard items for beamlines, regardless of the specific scientific objective of a particular beamline. A generic beamline layout formed the basis for this identification. This layout is based on a double-crystal monochromator as the first optical element, with the possibility of other elements to follow. Pre-engineering designs were then made of the identified standard components. The Beamline Standardization and Modularization Committee has reviewed these designs and provided very useful input regarding the specifications of these components. We realize that there will be other configurations that may require special or modified components. This Handbook in its current version (1.1) contains descriptions, specifications, and pre-engineering design drawings of these standard components. In the future, the APS plans to add engineering drawings of identified standard beamline components. Use of standard components should result in major cost reductions for CATs in the areas of beamline design and construction

  8. Secure coupling of hardware components

    NARCIS (Netherlands)

    Hoepman, J.H.; Joosten, H.J.M.; Knobbe, J.W.

    2011-01-01

    A method and a system for securing communication between at least a first and a second hardware components of a mobile device is described. The method includes establishing a first shared secret between the first and the second hardware components during an initialization of the mobile device and,

  9. Generic component failure data base

    International Nuclear Information System (INIS)

    Eide, S.A.; Calley, M.B.

    1992-01-01

    This report discusses comprehensive component generic failure data base which has been developed for light water reactor probabilistic risk assessments. The Nuclear Computerized Library for Assessing Reactor Reliability (NUCLARR) was used to generate component failure rates. Using this approach, most of the failure rates are based on actual plant data rather then existing estimates

  10. Active components in food supplements

    NARCIS (Netherlands)

    Siemelink M; Jansen EHJM; Piersma AH; Opperhuizen A; LEO

    2000-01-01

    The growing food supplement market, where supplements are both more diverse and more easily available (e.g. through Internet) formed the backdrop to the inventory of the active components in food supplements. The safety of an increased intake of food components via supplements was also at issue

  11. Component reliability for electronic systems

    CERN Document Server

    Bajenescu, Titu-Marius I

    2010-01-01

    The main reason for the premature breakdown of today's electronic products (computers, cars, tools, appliances, etc.) is the failure of the components used to build these products. Today professionals are looking for effective ways to minimize the degradation of electronic components to help ensure longer-lasting, more technically sound products and systems. This practical book offers engineers specific guidance on how to design more reliable components and build more reliable electronic systems. Professionals learn how to optimize a virtual component prototype, accurately monitor product reliability during the entire production process, and add the burn-in and selection procedures that are the most appropriate for the intended applications. Moreover, the book helps system designers ensure that all components are correctly applied, margins are adequate, wear-out failure modes are prevented during the expected duration of life, and system interfaces cannot lead to failure.

  12. Component Fragility Research Program: Phase 1 component prioritization

    International Nuclear Information System (INIS)

    Holman, G.S.; Chou, C.K.

    1987-06-01

    Current probabilistic risk assessment (PRA) methods for nuclear power plants utilize seismic ''fragilities'' - probabilities of failure conditioned on the severity of seismic input motion - that are based largely on limited test data and on engineering judgment. Under the NRC Component Fragility Research Program (CFRP), the Lawrence Livermore National Laboratory (LLNL) has developed and demonstrated procedures for using test data to derive probabilistic fragility descriptions for mechanical and electrical components. As part of its CFRP activities, LLNL systematically identified and categorized components influencing plant safety in order to identify ''candidate'' components for future NRC testing. Plant systems relevant to safety were first identified; within each system components were then ranked according to their importance to overall system function and their anticipated seismic capacity. Highest priority for future testing was assigned to those ''very important'' components having ''low'' seismic capacity. This report describes the LLNL prioritization effort, which also included application of ''high-level'' qualification data as an alternate means of developing probabilistic fragility descriptions for PRA applications

  13. Formalization in Component Based Development

    DEFF Research Database (Denmark)

    Holmegaard, Jens Peter; Knudsen, John; Makowski, Piotr

    2006-01-01

    We present a unifying conceptual framework for components, component interfaces, contracts and composition of components by focusing on the collection of properties or qualities that they must share. A specific property, such as signature, functionality behaviour or timing is an aspect. Each aspect...... may be specified in a formal language convenient for its purpose and, in principle, unrelated to languages for other aspects. Each aspect forms its own semantic domain, although a semantic domain may be parameterized by values derived from other aspects. The proposed conceptual framework is introduced...

  14. Three-component homeostasis control

    Science.gov (United States)

    Xu, Jin; Hong, Hyunsuk; Jo, Junghyo

    2014-03-01

    Two reciprocal components seem to be sufficient to maintain a control variable constant. However, pancreatic islets adapt three components to control glucose homeostasis. They are α (secreting glucagon), β (insulin), and δ (somatostatin) cells. Glucagon and insulin are the reciprocal hormones for increasing and decreasing blood glucose levels, while the role of somatostatin is unknown. However, it has been known how each hormone affects other cell types. Based on the pulsatile hormone secretion and the cellular interactions, this system can be described as coupled oscillators. In particular, we used the Landau-Stuart model to consider both amplitudes and phases of hormone oscillations. We found that the presence of the third component, δ cell, was effective to resist under glucose perturbations, and to quickly return to the normal glucose level once perturbed. Our analysis suggested that three components are necessary for advanced homeostasis control.

  15. Component Processes in Analogical Reasoning

    Science.gov (United States)

    Sternberg, Robert J.

    1977-01-01

    Describes alternative theoretical positions regarding (a) the component information processes used in analogical reasoning and (b) strategies for combining these processes. Also presents results from three experiments on analogical reasoning. (Author/RK)

  16. Passive Microwave Components and Antennas

    DEFF Research Database (Denmark)

    State-of-the-art microwave systems always require higher performance and lower cost microwave components. Constantly growing demands and performance requirements of industrial and scientific applications often make employing traditionally designed components impractical. For that reason, the design...... and development process remains a great challenge today. This problem motivated intensive research efforts in microwave design and technology, which is responsible for a great number of recently appeared alternative approaches to analysis and design of microwave components and antennas. This book highlights...... techniques. Modelling and computations in electromagnetics is a quite fast-growing research area. The recent interest in this field is caused by the increased demand for designing complex microwave components, modeling electromagnetic materials, and rapid increase in computational power for calculation...

  17. Metallurgical Laboratory and Components Testing

    Data.gov (United States)

    Federal Laboratory Consortium — In the field of metallurgy, TTC is equipped to run laboratory tests on track and rolling stock components and materials. The testing lab contains scanning-electron,...

  18. Metal binding by food components

    DEFF Research Database (Denmark)

    Tang, Ning

    for zinc binding by the investigated amino acids, peptides and proteins. The thiol group or imidazole group containing amino acids, peptides and proteins which exhibited strong zinc binding ability were further selected for interacting with zinc salts in relation to zinc absorption. The interactions...... between the above selected food components and zinc citrate or zinc phytate will lead to the enhanced solubility of zinc citrate or zinc phytate. The main driving force for this observed solubility enhancement is the complex formation between zinc and investigated food components as revealed by isothermal...... titration calorimetry and quantum mechanical calculations. This is due to the zinc binding affinity of the relatively softer ligands (investigated food components) will become much stronger than citrate or phytate when they present together in aqueous solution. This mechanism indicates these food components...

  19. Radiation effects in optical components

    International Nuclear Information System (INIS)

    Friebele, E.J.

    1987-01-01

    This report discusses components of high performance optical devices may be exposed to high energy radiation environments during their lifetime. The effect of these adverse environments depends upon a large number of parameters associated with the radiation (nature, energy, dose, dose rate, etc.) or the system (temperature, optical performance requirements, optical wavelength, optical power, path length, etc.), as well as the intrinsic susceptibility of the optical component itself to degradation

  20. Multiview Bayesian Correlated Component Analysis

    DEFF Research Database (Denmark)

    Kamronn, Simon Due; Poulsen, Andreas Trier; Hansen, Lars Kai

    2015-01-01

    are identical. Here we propose a hierarchical probabilistic model that can infer the level of universality in such multiview data, from completely unrelated representations, corresponding to canonical correlation analysis, to identical representations as in correlated component analysis. This new model, which...... we denote Bayesian correlated component analysis, evaluates favorably against three relevant algorithms in simulated data. A well-established benchmark EEG data set is used to further validate the new model and infer the variability of spatial representations across multiple subjects....

  1. Component protection based automatic control

    International Nuclear Information System (INIS)

    Otaduy, P.J.

    1992-01-01

    Control and safety systems as well as operation procedures are designed on the basis of critical process parameters limits. The expectation is that short and long term mechanical damage and process failures will be avoided by operating the plant within the specified constraints envelopes. In this paper, one of the Advanced Liquid Metal Reactor (ALMR) design duty cycles events is discussed to corroborate that the time has come to explicitly make component protection part of the control system. Component stress assessment and aging data should be an integral part of the control system. Then transient trajectory planning and operating limits could be aimed at minimizing component specific and overall plant component damage cost functions. The impact of transients on critical components could then be managed according to plant lifetime design goals. The need for developing methodologies for online transient trajectory planning and assessment of operating limits in order to facilitate the explicit incorporation of damage assessment capabilities to the plant control and protection systems is discussed. 12 refs

  2. Mechanical design of machine components

    CERN Document Server

    Ugural, Ansel C

    2015-01-01

    Mechanical Design of Machine Components, Second Edition strikes a balance between theory and application, and prepares students for more advanced study or professional practice. It outlines the basic concepts in the design and analysis of machine elements using traditional methods, based on the principles of mechanics of materials. The text combines the theory needed to gain insight into mechanics with numerical methods in design. It presents real-world engineering applications, and reveals the link between basic mechanics and the specific design of machine components and machines. Divided into three parts, this revised text presents basic background topics, deals with failure prevention in a variety of machine elements and covers applications in design of machine components as well as entire machines. Optional sections treating special and advanced topics are also included.Key Features of the Second Edition:Incorporates material that has been completely updated with new chapters, problems, practical examples...

  3. Towards Prognostics for Electronics Components

    Science.gov (United States)

    Saha, Bhaskar; Celaya, Jose R.; Wysocki, Philip F.; Goebel, Kai F.

    2013-01-01

    Electronics components have an increasingly critical role in avionics systems and in the development of future aircraft systems. Prognostics of such components is becoming a very important research field as a result of the need to provide aircraft systems with system level health management information. This paper focuses on a prognostics application for electronics components within avionics systems, and in particular its application to an Isolated Gate Bipolar Transistor (IGBT). This application utilizes the remaining useful life prediction, accomplished by employing the particle filter framework, leveraging data from accelerated aging tests on IGBTs. These tests induced thermal-electrical overstresses by applying thermal cycling to the IGBT devices. In-situ state monitoring, including measurements of steady-state voltages and currents, electrical transients, and thermal transients are recorded and used as potential precursors of failure.

  4. Automated cleaning of electronic components

    International Nuclear Information System (INIS)

    Drotning, W.; Meirans, L.; Wapman, W.; Hwang, Y.; Koenig, L.; Petterson, B.

    1994-01-01

    Environmental and operator safety concerns are leading to the elimination of trichloroethylene and chlorofluorocarbon solvents in cleaning processes that remove rosin flux, organic and inorganic contamination, and particulates from electronic components. Present processes depend heavily on these solvents for manual spray cleaning of small components and subassemblies. Use of alternative solvent systems can lead to longer processing times and reduced quality. Automated spray cleaning can improve the quality of the cleaning process, thus enabling the productive use of environmentally conscious materials, while minimizing personnel exposure to hazardous materials. We describe the development of a prototype robotic system for cleaning electronic components in a spray cleaning workcell. An important feature of the prototype system is the capability to generate the robot paths and motions automatically from the CAD models of the part to be cleaned, and to embed cleaning process knowledge into the automatically programmed operations

  5. Two component systems: physiological effect of a third component.

    Directory of Open Access Journals (Sweden)

    Baldiri Salvado

    Full Text Available Signal transduction systems mediate the response and adaptation of organisms to environmental changes. In prokaryotes, this signal transduction is often done through Two Component Systems (TCS. These TCS are phosphotransfer protein cascades, and in their prototypical form they are composed by a kinase that senses the environmental signals (SK and by a response regulator (RR that regulates the cellular response. This basic motif can be modified by the addition of a third protein that interacts either with the SK or the RR in a way that could change the dynamic response of the TCS module. In this work we aim at understanding the effect of such an additional protein (which we call "third component" on the functional properties of a prototypical TCS. To do so we build mathematical models of TCS with alternative designs for their interaction with that third component. These mathematical models are analyzed in order to identify the differences in dynamic behavior inherent to each design, with respect to functionally relevant properties such as sensitivity to changes in either the parameter values or the molecular concentrations, temporal responsiveness, possibility of multiple steady states, or stochastic fluctuations in the system. The differences are then correlated to the physiological requirements that impinge on the functioning of the TCS. This analysis sheds light on both, the dynamic behavior of synthetically designed TCS, and the conditions under which natural selection might favor each of the designs. We find that a third component that modulates SK activity increases the parameter space where a bistable response of the TCS module to signals is possible, if SK is monofunctional, but decreases it when the SK is bifunctional. The presence of a third component that modulates RR activity decreases the parameter space where a bistable response of the TCS module to signals is possible.

  6. Explanation components as interactive tools

    Energy Technology Data Exchange (ETDEWEB)

    Wahlster, W.

    1983-01-01

    The ability to explain itself is probably the most important criterion of the user-friendliness of interactive systems. Explanation aids in the form of simple help functions do not meet this criterion. The reasons for this are outlined. More promising is an explanation component which can give the user intelligible and context-oriented explanations. The essential requirement for this is the development of knowledge-based interactive systems using artificial intelligence methods and techniques. The authors report on experiences with the development of explanation components, in particular a number of examples from the HAM-ANS project. 12 references.

  7. Radioactive resistance of EEPROM components

    International Nuclear Information System (INIS)

    Loncar, B.; Novakovic, D.; Stankovic, S.; Osmokrovic, P.

    1999-01-01

    The aim of this paper is to examine the resistance of EEPROM components under the influence of gamma radiation. This paper is significant for military industry and space technology. Therefore the analysis of the degradation mechanisms of these components as well as the possibilities to increase their radiation resistance have been considered by many authors. Total dose results are presented for 28C64C EEPROM there is evidence that the first failure appeared for 1000 Gy total dose level. The obtained result are analyzed and explained theoretically via the interaction of gamma radiation with oxide layer. (author)

  8. Space storable propulsion components development

    Science.gov (United States)

    Hagler, R., Jr.

    1982-01-01

    The current development status of components to control the flow of propellants (liquid fluorine and hydrazine) in a demonstration space storable propulsion system is discussed. The criteria which determined the designs for the pressure regulator, explosive-actuated valves, propellant shutoff valve, latching solenoid-actuated valve and propellant filter are presented. The test philosophy that was followed during component development is outlined. The results from compatibility demonstrations for reusable connectors, flange seals, and CRES/Ti-6Al4V transition tubes and the evaluations of processes for welding (hand-held TIG, automated TIG, and EB), cleaning for fluorine service, and decontamination after fluorine exposure are described.

  9. Radiation effects on eye components

    Science.gov (United States)

    Durchschlag, H.; Fochler, C.; Abraham, K.; Kulawik, B.

    1999-08-01

    The most important water-soluble components of the vertebrate eye (lens proteins, aqueous humor, vitreous, hyaluronic acid, ascorbic acid) have been investigated in aqueous solution, after preceding X- or UV-irradiation. Spectroscopic, chromatographic, electrophoretic, hydrodynamic and analytic techniques have been applied, to monitor several radiation damages such as destruction of aromatic and sulfur-containing amino acids, aggregation, crosslinking, dissociation, fragmentation, and partial unfolding. Various substances were found which were able to protect eye components effectively against radiation, some of them being also of medical relevance.

  10. Latent semantics as cognitive components

    DEFF Research Database (Denmark)

    Petersen, Michael Kai; Mørup, Morten; Hansen, Lars Kai

    2010-01-01

    Cognitive component analysis, defined as an unsupervised learning of features resembling human comprehension, suggests that the sensory structures we perceive might often be modeled by reducing dimensionality and treating objects in space and time as linear mixtures incorporating sparsity...... emotional responses can be encoded in words, we propose a simplified cognitive approach to model how we perceive media. Representing song lyrics in a vector space of reduced dimensionality using LSA, we combine bottom-up defined term distances with affective adjectives, that top-down constrain the latent......, which we suggest might function as cognitive components for perceiving the underlying structure in lyrics....

  11. Environmental Forces - Some Esthetic Components.

    Science.gov (United States)

    Severino, D. Alexander

    Although our system of mass culture has raised our civilization to an extremely high level of material success and affluence, the fact remains that this system has the inherent flaw of not fully recognizing the esthetic needs of man. To overcome this weakness we need to re-introduce into the system a sizable component of first-hand experience…

  12. Components in the interstellar medium

    International Nuclear Information System (INIS)

    Martin, E.R.

    1981-01-01

    An analysis is made of the lines of sight toward 32 stars with a procedure that gives velocity components for various interstellar ions. The column densities found for species expected to be relatively undepleted are used to estimate the column density of neutral hydrogen in each component. Whenever possible, the molecular hydrogen excitation temperature, abundances (relative to S II), electron density, and hydrogen volume density are calculated for each component. The results for each star are combined to give total HI column density as a function of (LSR) velocity. The derived velocities correspond well with those found in optical studies. The mean electron density is found to be approximately constant with velocity, but the mean hydrogen volume density is found to vary. The data presented here are consistent with the assumption that some of the velocity components are due to circumstellar material. The total HI column density toward a given star is generally in agreement with Lyman alpha measurements, but ionization and abundance effects are important toward some stars. The total HI column density is found to vary exponentially with velocity (for N(HI)> 10 17 cm -2 ), with an indication that the velocity dispersion at low column densities (N(HI) 17 cm -2 ) is approximately constant. An estimate is made of the kinetic energy density due to cloud motion which depends only on the total HI column density as a function of velocity. The value of 9 x 10 42 erg/pc 3 is in good agreement with a theoretical prediction

  13. Embedded 100 Gbps Photonic Components:

    Energy Technology Data Exchange (ETDEWEB)

    Kuznia, Charlie

    2018-04-26

    This innovation to fiber optic component technology increases the performance, reduces the size and reduces the power consumption of optical communications within dense network systems, such as advanced distributed computing systems and data centers. VCSEL technology is enabling short-reach (< 100 m) and >100 Gbps optical interconnections over multi-mode fiber in commercial applications.

  14. Inspection of disposal canisters components

    International Nuclear Information System (INIS)

    Pitkaenen, J.

    2013-12-01

    This report presents the inspection techniques of disposal canister components. Manufacturing methods and a description of the defects related to different manufacturing methods are described briefly. The defect types form a basis for the design of non-destructive testing because the defect types, which occur in the inspected components, affect to choice of inspection methods. The canister components are to nodular cast iron insert, steel lid, lid screw, metal gasket, copper tube with integrated or separate bottom, and copper lid. The inspection of copper material is challenging due to the anisotropic properties of the material and local changes in the grain size of the copper material. The cast iron insert has some acoustical material property variation (attenuation, velocity changes, scattering properties), which make the ultrasonic inspection demanding from calibration point of view. Mainly three different methods are used for inspection. Ultrasonic testing technique is used for inspection of volume, eddy current technique, for copper components only, and visual testing technique are used for inspection of the surface and near surface area

  15. Component effects in mixture experiments

    International Nuclear Information System (INIS)

    Piepel, G.F.

    1980-01-01

    In a mixture experiment, the response to a mixture of q components is a function of the proportions x 1 , x 2 , ..., x/sub q/ of components in the mixture. Experimental regions for mixture experiments are often defined by constraints on the proportions of the components forming the mixture. The usual (orthogonal direction) definition of a factor effect does not apply because of the dependence imposed by the mixture restriction, /sup q/Σ/sub i=1/ x/sub i/ = 1. A direction within the experimental region in which to compute a mixture component effect is presented and compared to previously suggested directions. This new direction has none of the inadequacies or errors of previous suggestions while having a more meaningful interpretation. The distinction between partial and total effects is made. The uses of partial and total effects (computed using the new direction) in modification and interpretation of mixture response prediction equations are considered. The suggestions of the paper are illustrated in an example from a glass development study in a waste vitrification program. 5 figures, 3 tables

  16. Modelling Livestock Component in FSSIM

    NARCIS (Netherlands)

    Thorne, P.J.; Hengsdijk, H.; Janssen, S.J.C.; Louhichi, K.; Keulen, van H.; Thornton, P.K.

    2009-01-01

    This document summarises the development of a ruminant livestock component for the Farm System Simulator (FSSIM). This includes treatments of energy and protein transactions in ruminant livestock that have been used as a basis for the biophysical simulations that will generate the input production

  17. A forgotten component of biodiversity

    Indian Academy of Sciences (India)

    2011-07-08

    Jul 8, 2011 ... Home; Journals; Journal of Biosciences; Volume 36; Issue 4. Clipboard: Helminth richness in Arunachal Pradesh fishes: A forgotten component of biodiversity. Amit Tripathi. Volume 36 Issue 4 September 2011 pp 559-561. Fulltext. Click here to view fulltext PDF. Permanent link:

  18. Detecting decay in wood components

    Science.gov (United States)

    R.J. Ross; X. Wang; B.K. Brashaw

    2005-01-01

    This chapter presents a summary of the Wood and Timber Condition Assessment Manual. It focuses on current inspection techniques for decay detection and provides guidelines on the use of various non-destructive evaluation (NDE) methods in locating and defining areas of deterioration in timber bridge components and other civil structures.

  19. Cold component flow in a two-component mirror machine

    International Nuclear Information System (INIS)

    Rognlien, T.D.

    1975-12-01

    Steady-state solutions are given for the flow characteristics along the magnetic field of the cold plasma component in a two-component mirror machine. The hot plasma component is represented by a fixed density profile. The fluid equations are used to describe the cold plasma, which is assumed to be generated in a localized region at one end of the machine. The ion flow speed, v/sub i/, is required to satisfy the Bohm sheath condition at the end walls, i.e., v/sub i/ greater than or equal to c/sub s/, where c/sub s/ is the ion-acoustic speed. For the case when the cold plasma density, n/sub c/, is much less than the hot plasma density, n/sub h/, the cold plasma is stagnant and does not penetrate through the machine in the zero temperature case. The effect of a finite temperature is to allow for the penetration of a small amount of cold plasma through the machine. For the density range n/sub c/ approximately n/sub h/, the flow solutions are asymmetric about the midplane and have v/sub i/ = c/sub s/ near the midplane. Finally, for n/sub c/ much greater than n/sub h/, the solutions become symmetric about the midplane and approach the Lee--McNamara type solutions with v/sub i/ = c/sub s/ near the mirror throats

  20. Cylinder components properties, applications, materials

    CERN Document Server

    2016-01-01

    Owing to the ever-increasing requirements to be met by gasoline and diesel engines in terms of CO2 reduction, emission behavior, weight, and service life, a comprehensive understanding of combustion engine components is essential today. It is no longer possible for professionals in automotive engineering to manage without the corresponding expertise, whether they work in the field of design, development, testing, or maintenance. This technical book provides in-depth answers to questions about design, production, and machining of cylinder components. In this second edition, every section has been revised and expanded to include the latest developments in the combustion engine. Content Piston rings Piston pins and piston pin circlips Bearings Connecting rods Crankcase and cylinder liners Target audience Engineers in the field of engine development and maintenanceLecturers and students in the areas of mechanical engineering, engine technology, and vehicle constructionAnyone interested in technology Publisher MAH...

  1. Tritium in fusion reactor components

    International Nuclear Information System (INIS)

    Watson, J.S.; Fisher, P.W.; Talbot, J.B.

    1980-01-01

    When tritium is used in a fusion energy experiment or reactor, several implications affect and usually restrict the design and operation of the system and involve questions of containment, inventory, and radiation damage. Containment is expected to be particularly important both for high-temperature components and for those components that are prone to require frequent maintenance. Inventory is currently of major significance in cases where safety and environmental considerations limit the experiments to very low levels of tritium. Fewer inventory restrictions are expected as fusion experiments are placed in more-remote locations and as the fusion community gains experience with the use of tritium. However, the advent of power-producing experiments with high-duty cycle will again lead to serious difficulties based principally on tritium availability; cyclic operations with significant regeneration times are the principal problems

  2. HG ion thruster component testing

    Science.gov (United States)

    Mantenieks, M. A.

    1979-01-01

    Cathodes, isolators, and vaporizers are critical components in determining the performance and lifetime of mercury ion thrusters. The results of life tests of several of these components are reported. A 30-cm thruster CIV test in a bell jar has successfully accumulated over 26,000 hours. The cathode has undergone 65 restarts during the life test without requiring any appreciable increases in starting power. Recently, all restarts have been achieved with only the 44 volt keeper supply with no change required in the starting power. Another ongoing 30-cm Hg thruster cathode test has successfully passed the 10,000 hour mark. A solid-insert, 8-cm thruster cathode has accumulated over 4,000 hours of thruster operation. All starts have been achieved without the use of a high voltage ignitor. The results of this test indicate that the solid impregnated insert is a viable neutralizer cathode for the 8-cm thruster.

  3. Component processes underlying future thinking.

    Science.gov (United States)

    D'Argembeau, Arnaud; Ortoleva, Claudia; Jumentier, Sabrina; Van der Linden, Martial

    2010-09-01

    This study sought to investigate the component processes underlying the ability to imagine future events, using an individual-differences approach. Participants completed several tasks assessing different aspects of future thinking (i.e., fluency, specificity, amount of episodic details, phenomenology) and were also assessed with tasks and questionnaires measuring various component processes that have been hypothesized to support future thinking (i.e., executive processes, visual-spatial processing, relational memory processing, self-consciousness, and time perspective). The main results showed that executive processes were correlated with various measures of future thinking, whereas visual-spatial processing abilities and time perspective were specifically related to the number of sensory descriptions reported when specific future events were imagined. Furthermore, individual differences in self-consciousness predicted the subjective feeling of experiencing the imagined future events. These results suggest that future thinking involves a collection of processes that are related to different facets of future-event representation.

  4. Nuclear power plant component protection

    International Nuclear Information System (INIS)

    Michel, E.; Ruf, R.; Dorner, H.

    1976-01-01

    Described is a nuclear power plant installation which includes a concrete biological shield forming a pit in which a reactor pressure vessel is positioned. A steam generator on the outside of the shield is connected with the pressure vessel via coolant pipe lines which extend through the shield, the coolant circulation being provided by a coolant pump which is also on the outside of the shield. To protect these components on the outside of the shield and which are of mainly or substantially cylindrical shape, semicylindrical concrete segments are interfitted around them to form complete outer cylinders which are retained against outward separation radially from the components, by rings of high tensile steel which may be interspaced so closely that they provide, in effect, an outer steel cylinder. The invention is particularly applicable to pressurized-water coolant reactor installations

  5. Open Component Portability Infrastructure (OPENCPI)

    Science.gov (United States)

    2013-03-01

    declaration of the authored worker that must be implemented . If there is existing legacy VHDL entity architecture, then it is wrapped or modified to...that the software implementations were written to. Since all of the original code was VHDL , the HDL Authoring Model for VHDL was enhanced to meet...engineering process. This application was completed for the execution of all the components, the software implementations , and the VHDL skeletons for the

  6. Behavior Protocols for Software Components

    Czech Academy of Sciences Publication Activity Database

    Plášil, František; Višňovský, Stanislav

    2002-01-01

    Roč. 28, č. 11 (2002), s. 1056-1076 ISSN 0098-5589 R&D Projects: GA AV ČR IAA2030902; GA ČR GA201/99/0244 Grant - others:Eureka(XE) Pepita project no.2033 Institutional research plan: AV0Z1030915 Keywords : behavior protocols * component-based programming * software architecture Subject RIV: JC - Computer Hardware ; Software Impact factor: 1.170, year: 2002

  7. Chemical decontamination of reactor components

    International Nuclear Information System (INIS)

    Riess, R.; Berthold, H.O.

    1977-08-01

    A solution for the decontamination of reactor components of the primary system was developed. This solution is a modification of the APAC- (Alkaline Permanganate Ammonium Citrate) system described in the literature. The most important advantage of the present solution over the APAC-method is that it does not induce any selective corrosion attack on materials like stainless steel (austenitic), Inconel 600 and Incoloy 800. (orig.) [de

  8. The risk components of liquidity

    OpenAIRE

    Chollete, Lorán; Næs, Randi; Skjeltorp, Johannes A.

    2008-01-01

    Does liquidity risk differ depending on our choice of liquidity proxy? Unlike literature that considers common liquidity variation, we focus on identifying different components of liquidity, statistically and economically, using more than a decade of US transaction data. We identify three main statistical liquidity factors which are utilized in a linear asset pricing framework. We motivate a correspondence of the statistical factors to traditional dimensions of liquidity as well as the notion...

  9. Reformulating Component Identification as Document Analysis Problem

    NARCIS (Netherlands)

    Gross, H.G.; Lormans, M.; Zhou, J.

    2007-01-01

    One of the first steps of component procurement is the identification of required component features in large repositories of existing components. On the highest level of abstraction, component requirements as well as component descriptions are usually written in natural language. Therefore, we can

  10. Coherent systems with multistate components

    International Nuclear Information System (INIS)

    Caldarola, L.

    1980-01-01

    The basic rules of the Boolean algebra with restrictions on variables are briefly recalled. This special type of Boolean algebra allows one to handle fault trees of systems made of multistate (two or more than two states) components. Coherent systems are defined in the case of multistate components. This definition is consistent with that originally suggested by Barlow in the case of binary (two states) components. The basic properties of coherence are described and discussed. Coherent Boolean functions are also defined. It is shown that these functions are irredundant, that is they have only one base which is at the same time complete and irredundant. However, irredundant functions are not necessarily coherent. Finally a simplified algorithm for the calculation of the base of a coherent function is described. In the case that the function is not coherent, the algorithm can be used to reduce the size of the normal disjunctive form of the function. This in turn eases the application of the Nelson algorithm to calculate the complete base of the function. The simplified algorithm has been built in the computer program MUSTAFA-1. In a sample case the use of this algorithm caused a reduction of the CPU time by a factor of about 20. (orig.)

  11. Radiation damage to electronic components

    International Nuclear Information System (INIS)

    Battisti, S.; Bossart, R.; Schoenbacher, H.; Van de Voorde, M.

    1975-01-01

    Characteristic properties are presented of some 40 different electronic components (resistors, capacitors, diodes, transistors, and integrated circuits) which were irradiated in a nuclear reactor up to 1015 n/cm 2 (E > 1 MeV). Complete circuits (e.g. RF amplifiers and detectors, mixers, differential amplifiers, voltage-to-frequency converters, oscillators, power supplies) were irradiated near the CERN Intersecting Storage Rings up to 106 rad(RPL) (dose measured with radiophotoluminescent dosimeters) under simulated operational conditions. Representative measured parameters, such as resistance, capacitance, forward voltage, reverse current, toggle frequencies, are given in graphs as a function of radiation dose. The results are discussed in detail and lead to the over-all conclusion that the operation of electronic components and circuits is seriously affected by radiation environments with doses in the order of 10 13 n/cm 2 or 10 4 rad(RPL); some components and circuits fail completely at doses of 10 14 n/cm 2 or 10 5 rad(RPL). (Author)

  12. Fusion-component lifetime analysis

    International Nuclear Information System (INIS)

    Mattas, R.F.

    1982-09-01

    A one-dimensional computer code has been developed to examine the lifetime of first-wall and impurity-control components. The code incorporates the operating and design parameters, the material characteristics, and the appropriate failure criteria for the individual components. The major emphasis of the modeling effort has been to calculate the temperature-stress-strain-radiation effects history of a component so that the synergystic effects between sputtering erosion, swelling, creep, fatigue, and crack growth can be examined. The general forms of the property equations are the same for all materials in order to provide the greatest flexibility for materials selection in the code. The individual coefficients within the equations are different for each material. The code is capable of determining the behavior of a plate, composed of either a single or dual material structure, that is either totally constrained or constrained from bending but not from expansion. The code has been utilized to analyze the first walls for FED/INTOR and DEMO and to analyze the limiter for FED/INTOR

  13. Radiation effects on eye components

    International Nuclear Information System (INIS)

    Durchschlag, H.; Fochler, C.; Abraham, K.; Kulawik, B.

    1998-01-01

    The radiation damage (X-ray, UV light) of the most important components of the vertebrate eye (crystallins and other proteins, hyaluronic acid, vitreous, aqueous humour, ascorbic acid) has been investigated by various methods of physical chemistry. UV absorption and fluorescence spectroscopy as well as circular dichroism unveiled changes of the chromophores/fluorophores of the constituent biopolymers and low-molecular components, together with alterations of helix content and the occurrence of aggregation. Size-exclusion chromatography, analytical ultracentrifugation, densimetry, viscometry and light scattering experiments monitored changes of the global structure of proteins and polysaccharides involved. Electrophoreses allowed conclusions on fragmentation, unfolding and crosslinking. Analytical methods provided information regarding the integrity of groups of special concern (SH, SS) and revealed the existence of stable noxious species (H 2 O 2 ). By means of various measures and additives, manifold modifications of the impact of both ionizing and nonionizing radiation may be achieved. Caused by differences in the primary reactions, eye polymers are protected efficaciously by typical OH radical scavengers against X-irradiation, whereas compounds which exhibit absorption behavior in the UV range turn out to act as potent protectives ('chemical filters') against UV light. A few substances, such as ascorbate, are able to provide protection against both sorts of radiation and are even able to exhibit a slight chemical repair of already damaged particles. The results obtained are of importance for understanding pathological alterations of the eye (loss of transparency, cataractogenesis) and for developing new strategies for protection and repair of eye components. (author)

  14. Web components and the semantic web

    OpenAIRE

    Casey, Maire; Pahl, Claus

    2003-01-01

    Component-based software engineering on the Web differs from traditional component and software engineering. We investigate Web component engineering activites that are crucial for the development,com position, and deployment of components on the Web. The current Web Services and Semantic Web initiatives strongly influence our work. Focussing on Web component composition we develop description and reasoning techniques that support a component developer in the composition activities,fo cussing...

  15. Component Control System for a Vehicle

    Science.gov (United States)

    Fraser-Chanpong, Nathan (Inventor); Spain, Ivan (Inventor); Dawson, Andrew D. (Inventor); Bluethmann, William J. (Inventor); Lee, Chunhao J. (Inventor); Vitale, Robert L. (Inventor); Guo, Raymond (Inventor); Waligora, Thomas M. (Inventor); Akinyode, Akinjide Akinniyi (Inventor); Reed, Ryan M. (Inventor)

    2016-01-01

    A vehicle includes a chassis, a modular component, and a central operating system. The modular component is supported by the chassis. The central operating system includes a component control system, a primary master controller, and a secondary master controller. The component control system is configured for controlling the modular component. The primary and secondary master controllers are in operative communication with the component control system. The primary and secondary master controllers are configured to simultaneously transmit commands to the component control system. The component control system is configured to accept commands from the secondary master controller only when a fault occurs in the primary master controller.

  16. Experimental qualification of nuclear components

    Energy Technology Data Exchange (ETDEWEB)

    Alliot, P; Fronte, T; Genty, F [FRAMATOME - Cedex 16, Paris la Defense (France)

    1988-07-01

    In the process of showing the adequacy of the seismic design of French PWR reactor, Fermat has repeatedly used dynamic testing on actual nuclear reactor components both on site and in manufacturing shops. The objective and results of a few representative examples of this on-site experimental verification are presented in this paper: the experimental dynamic analysis of a manipulator crane; the investigation of the seismic behaviour of fuel storage racks equipped with aseismic bearing devices. Difficulties to select satisfactory testing methods are also discussed for the particular case of the electrical cabinets. (author)

  17. Lifetime of superheated steam components

    International Nuclear Information System (INIS)

    Stoklossa, K.H.; Oude-Hengel, H.H.; Kraechter, H.J.

    1974-01-01

    The current evaluation schemes in use for judging the lifetime expectations of superheated steam components are compared with each other. The influence of pressure and temperature fluctuations, the differences in the strength of the wall, and the spread band of constant-strainrates are critically investigated. The distribution of these contributory effects are demonstrated in the hight of numerous measuring results. As an important supplement to these evaluation schemes a newly developed technique is introduced which is designed to calculate failure probabilities. (orig./RW) [de

  18. Cooling concepts for HTS components

    International Nuclear Information System (INIS)

    Binneberg, A.; Buschmann, H.; Neubert, J.

    1993-01-01

    HTS components require that low-cost, reliable cooling systems be used. There are no general solutions to such systems. Any cooling concept has to be tailored to the specific requirements of a system. The following has to he taken into consideration when designing cooling concepts: - cooling temperature - constancy and controllability of the cooling temperature - cooling load and refrigerating capacity - continuous or discontinuous mode - degree of automation - full serviceability or availability before evacuation -malfunctions caused by microphonic, thermal or electromagnetic effects -stationary or mobile application - investment and operating costs (orig.)

  19. Bioactivity of Minor Milk Components

    DEFF Research Database (Denmark)

    Nguyen, Duc Ninh

    . In particular, 3-15% of very low birth weight preterm infants suffer from the most servere form of intestinal inflammation, known as necrotizing enterocolitis (NEC). This disease is incurable with a high mortality rate of 15-30%. Mother’s breast milk consists of different bioactive constituents...... of infant formula. Thereafter, bioactive milk components which were preserved in gently-processed infant formula were selected for further investigation of their immunomodulatory activity in cell and preterm pig models. We hope this project will contribute to the research on the development of new...

  20. Experimental qualification of nuclear components

    International Nuclear Information System (INIS)

    Alliot, P.; Fronte, T.; Genty, F.

    1988-01-01

    In the process of showing the adequacy of the seismic design of French PWR reactor, Fermat has repeatedly used dynamic testing on actual nuclear reactor components both on site and in manufacturing shops. The objective and results of a few representative examples of this on-site experimental verification are presented in this paper: the experimental dynamic analysis of a manipulator crane; the investigation of the seismic behaviour of fuel storage racks equipped with aseismic bearing devices. Difficulties to select satisfactory testing methods are also discussed for the particular case of the electrical cabinets. (author)

  1. Failures on stainless steel components

    International Nuclear Information System (INIS)

    Haenninen, H.

    1994-01-01

    Economic losses due to failure mainly by corrosion in process and nuclear industries are considered. In these industries the characteristics of different forms of corrosion and their economic effects are fairly well known and, especially, in nuclear industry the assessment of corrosion related costs has been comprehensive. In both industries the economic losses resulting from environmentally enhanced cracking of stainless steel components and the accompanying failures and outages have been considerable, owing as much to the frequency as the unpredictability of such occurrences. (orig.)

  2. Anthropological Component of Descartes’ Ontology

    Directory of Open Access Journals (Sweden)

    Anatolii M. Malivskyi

    2014-06-01

    Full Text Available The purpose of the article is to outline and comprehend the Descartes’ theory about anthropological component of ontology as the most important part of his philosophy. The accomplishment of this purpose covers the successive solution of the following tasks: 1 review of the research literature concerning the problem of human’s presence and the individual nature of truth; 2 emphasize the ambivalence of the basic intention of his legacy; 3 justify the thesis about constitutivity of human’s presence and comprehend passions as the form of disclosure of ontology’s anthropological component. Methodology. The use of the euristic potential of phenomenology, postpositivism and postmodernism makes it possible to emphasize the multiple-layer and multiple-meaning classical philosophy works, to comprehend the limitation and scarcity of the naïve-enlightening vision of human nature and to look for a new reception of European classics that provides the overcoming of established nihilism and pessimism concerning the interpretation of human nature. Scientific novelty. It is the first time that anthropological component of Descartes’ ontology became an object of particular attention. It previously lacked attention because of following main reasons: 1 traditional underestimating of the fact of Descartes’ legacy incompleteness as an unrealized anthropological project and 2 lack of proper attention to the individual nature of truth. The premise for its constructive overcoming is the attention to ambivalence of the basic intention and the significance of ethics in the philosopher’s legacy. His texts and research literature allow confirming the constitutive nature of human’s presence and passions as the key form of disclosure of the ontology anthropological component. Conclusions. The established tradition of interpretation the Descartes’ philosophizing nature as the filiation process of impersonal knowledge loses its cogency these days. The

  3. ANTHROPOLOGICAL COMPONENT OF DESCARTES’ ONTOLOGY

    Directory of Open Access Journals (Sweden)

    Anatolii M. Malivskyi

    2014-06-01

    Full Text Available The purpose of the article is to outline and comprehend the Descartes’ theory about anthropological component of ontology as the most important part of his philosophy. The accomplishment of this purpose covers the successive solution of the following tasks: 1 review of the research literature concerning the problem of human’s presence and the individual nature of truth; 2 emphasize the ambivalence of the basic intention of his legacy; 3 justify the thesis about constitutivity of human’s presence and comprehend passions as the form of disclosure of ontology’s anthropological component. Methodology. The use of the euristic potential of phenomenology, postpositivism and postmodernism makes it possible to emphasize the multiple-layer and multiple-meaning classical philosophy works, to comprehend the limitation and scarcity of the naïve-enlightening vision of human nature and to look for a new reception of European classics that provides the overcoming of established nihilism and pessimism concerning the interpretation of human nature. Scientific novelty. It is the first time that anthropological component of Descartes’ ontology became an object of particular attention. It previously lacked attention because of following main reasons: 1 traditional underestimating of the fact of Descartes’ legacy incompleteness as an unrealized anthropological project and 2 lack of proper attention to the individual nature of truth. The premise for its constructive overcoming is the attention to ambivalence of the basic intention and the significance of ethics in the philosopher’s legacy. His texts and research literature allow confirming the constitutive nature of human’s presence and passions as the key form of disclosure of the ontology anthropological component. Conclusions. The established tradition of interpretation the Descartes’ philosophizing nature as the filiation process of impersonal knowledge loses its cogency these days. The

  4. Components of Adenovirus Genome Packaging

    Science.gov (United States)

    Ahi, Yadvinder S.; Mittal, Suresh K.

    2016-01-01

    Adenoviruses (AdVs) are icosahedral viruses with double-stranded DNA (dsDNA) genomes. Genome packaging in AdV is thought to be similar to that seen in dsDNA containing icosahedral bacteriophages and herpesviruses. Specific recognition of the AdV genome is mediated by a packaging domain located close to the left end of the viral genome and is mediated by the viral packaging machinery. Our understanding of the role of various components of the viral packaging machinery in AdV genome packaging has greatly advanced in recent years. Characterization of empty capsids assembled in the absence of one or more components involved in packaging, identification of the unique vertex, and demonstration of the role of IVa2, the putative packaging ATPase, in genome packaging have provided compelling evidence that AdVs follow a sequential assembly pathway. This review provides a detailed discussion on the functions of the various viral and cellular factors involved in AdV genome packaging. We conclude by briefly discussing the roles of the empty capsids, assembly intermediates, scaffolding proteins, portal vertex and DNA encapsidating enzymes in AdV assembly and packaging. PMID:27721809

  5. Bioactive Components in Fish Venoms

    Science.gov (United States)

    Ziegman, Rebekah; Alewood, Paul

    2015-01-01

    Animal venoms are widely recognized excellent resources for the discovery of novel drug leads and physiological tools. Most are comprised of a large number of components, of which the enzymes, small peptides, and proteins are studied for their important bioactivities. However, in spite of there being over 2000 venomous fish species, piscine venoms have been relatively underrepresented in the literature thus far. Most studies have explored whole or partially fractioned venom, revealing broad pharmacology, which includes cardiovascular, neuromuscular, cytotoxic, inflammatory, and nociceptive activities. Several large proteinaceous toxins, such as stonustoxin, verrucotoxin, and Sp-CTx, have been isolated from scorpaenoid fish. These form pores in cell membranes, resulting in cell death and creating a cascade of reactions that result in many, but not all, of the physiological symptoms observed from envenomation. Additionally, Natterins, a novel family of toxins possessing kininogenase activity have been found in toadfish venom. A variety of smaller protein toxins, as well as a small number of peptides, enzymes, and non-proteinaceous molecules have also been isolated from a range of fish venoms, but most remain poorly characterized. Many other bioactive fish venom components remain to be discovered and investigated. These represent an untapped treasure of potentially useful molecules. PMID:25941767

  6. Safety engineering with COTS components

    International Nuclear Information System (INIS)

    O'Halloran, Mark; Hall, Jon G.; Rapanotti, Lucia

    2017-01-01

    Safety-critical systems are becoming more widespread, complex and reliant on software. Increasingly they are engineered through (COTS) (Commercial Off The Shelf) components to alleviate the spiralling costs and development time, often in the context of complex supply chains. A parallel increased concern for safety has resulted in a variety of safety standards, with a growing consensus that a safety life cycle is needed which is fully integrated with the design and development life cycle, to ensure that safety has appropriate influence on the design decisions as system development progresses. In this article we explore the application of an integrated approach to safety engineering in which assurance drives the engineering process. The paper reports on the outcome of a case study on a live industrial project with a view to evaluate: its suitability for application in a real-world safety engineering setting; its benefits and limitations in counteracting some of the difficulties of safety engineering with (COTS) components across supply chains; and, its effectiveness in generating evidence which can contribute directly to the construction of safety cases. - Highlights: • Assurance as effective driver for COTS-based safety-critical system development. • Engages stakeholders, captures requirements and provides rich traceability. • Shares appropriate safety requirements across the supply chain.

  7. Tipping device for large components

    International Nuclear Information System (INIS)

    Guigon, J.P.; Beraudier, D.

    1984-01-01

    For large components machining as components of a pressurized water reactor, it is necessary to have means allowing to present them in a position determined with regard to the machine tool used. The aim of the invention is a tipping device which consists of a base resting on the ground, a support-table mounted on this base, moving in rotation with the aid of at least a pivot joint of which axis is horizontal and parallel to the table and a gear pivot allowing to get a very good precision for the orientation of the piece and a very good stability whatever the orientation may be. The output shaft pinion of the base meshes with a gear wheel segment fixed to the table structure. Safety straps fasten the table structure to the base, as they are secured by horizontal pins. The toe pins run in straight slot holes incorporated in base jaws. The table rotation may be controlled by a spring-loaded braking mechanism which acts on the pivot axis and can be released by a hydraulic jack. The hydraulic pressure is used to prevent motor operation, unless the brakes have been released [fr

  8. Food components with anticaries activity.

    Science.gov (United States)

    Gazzani, Gabriella; Daglia, Maria; Papetti, Adele

    2012-04-01

    Caries is the most common oral infectious disease in the world. Its development is influenced also by diet components that interfere with pathogen mutans group Streptococci (MGS) activity. A very active research to identify functional foods and their components that are generally recognised as safe has been ongoing, with the aim of developing alternative approaches, to the use of synthetic chlorhexidine, and at the reduction or prevention of caries. Until now convincing evidence exists only for green tea as a functional food for oral health, partly owing to its high content of catechins, especially epigallocatechin-gallate. A number of other foods showed potential anticaries activity. Some other foods able to act against MGS growth and/or their virulence factors in in vitro tests are: apple, red grape seeds, red wine (proanthocyanidins), nutmeg (macelignan), ajowan caraway (nafthalen-derivative), coffee (trigonelline, nicotinic and chlorogenic acids, melanoidins), barley coffee (melanoidins), chicory and mushroom (quinic acid). In vivo anticaries activity has been shown by cranberry (procyanidins), glycyrrhiza root (glycyrrhizol-A), myrtus ethanolic extract, garlic aqueous extract, cocoa extracts (procyanidins), and propolis (apigenin, tt-farnesol). Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Interpretable functional principal component analysis.

    Science.gov (United States)

    Lin, Zhenhua; Wang, Liangliang; Cao, Jiguo

    2016-09-01

    Functional principal component analysis (FPCA) is a popular approach to explore major sources of variation in a sample of random curves. These major sources of variation are represented by functional principal components (FPCs). The intervals where the values of FPCs are significant are interpreted as where sample curves have major variations. However, these intervals are often hard for naïve users to identify, because of the vague definition of "significant values". In this article, we develop a novel penalty-based method to derive FPCs that are only nonzero precisely in the intervals where the values of FPCs are significant, whence the derived FPCs possess better interpretability than the FPCs derived from existing methods. To compute the proposed FPCs, we devise an efficient algorithm based on projection deflation techniques. We show that the proposed interpretable FPCs are strongly consistent and asymptotically normal under mild conditions. Simulation studies confirm that with a competitive performance in explaining variations of sample curves, the proposed FPCs are more interpretable than the traditional counterparts. This advantage is demonstrated by analyzing two real datasets, namely, electroencephalography data and Canadian weather data. © 2015, The International Biometric Society.

  10. GMES Space Component: Programme overview

    Science.gov (United States)

    Aschbacher, J.; Milagro-Perez, M. P.

    2012-04-01

    The European Union (EU) and the European Space Agency (ESA) have developed the Global Monitoring for Environment and Security (GMES) programme as Europe's answer to the vital need for joined-up data about our climate, environment and security. Through a unique combination of satellite, atmospheric and Earth-based monitoring systems, the initiative will provide new insight into the state of the land, sea and air, providing policymakers, scientists, businesses and the public with accurate and timely information. GMES capabilities include monitoring and forecasting of climatic change, flood risks, soil and coastal erosion, crop and fish resources, air pollution, greenhouse gases, iceberg distribution and snow cover, among others. To accomplish this, GMES has been divided into three main components: Space, In-situ and Services. The Space Component, led by ESA, comprises five types of new satellites called Sentinels that are being developed by ESA specifically to meet the needs of GMES, the first of which to be launched in 2013. These missions carry a range of technologies, such as radar and multi-spectral imaging instruments for land, ocean and atmospheric monitoring. In addition, access to data from the so-called Contributing Missions guarantees that European space infrastructure is fully used for GMES. An integrated Ground Segment ensures access to Sentinels and Contributing Missions data. The in-situ component, under the coordination of the European Environment Agency (EEA), is composed of atmospheric and Earth based monitoring systems, and based on established networks and programmes at European and international levels. The European Commission is in charge of implementing the services component of GMES and of leading GMES overall. GMES services, fed with data from the Space and In-situ components, will provide essential information in five main domains, atmosphere, ocean and land monitoring as well as emergency response and security. Climate change has been added

  11. Pathogen reduction of blood components.

    Science.gov (United States)

    Solheim, Bjarte G

    2008-08-01

    Thanks to many blood safety interventions introduced in developed countries the risk of transfusion transmitted infections has become exceedingly small in these countries. However, emerging pathogens still represent a serious challenge, as demonstrated by West Nile virus in the US and more recently by Chikungunya virus in the Indian Ocean. In addition bacterial contamination, particularly in platelets, and protozoa transmitted by blood components still represent sizeable risks in developed countries. In developing countries the risk of all transfusion transmitted infections is still high due to insufficient funding and organisation of the health service. Pathogen reduction of pooled plasma products has virtually eliminated the risk of transfusion transmitted infections, without compromising the quality of the products significantly. Pathogen reduction of blood components has been much more challenging. Solvent detergent treatment which has been so successfully applied for plasma products dissolves cell membranes, and can, therefore, only be applied for plasma and not for cellular blood components. Targeting of nucleic acids has been another method for pathogen inactivation of plasma and the only approach possible for cellular blood products. As documented in more than 15 year's track record, solvent detergent treatment of pooled plasma can yield high quality plasma. The increased risk for contamination by unknown viruses due to pooling is out weighed by elimination of TRALI, significant reduction in allergic reactions and standardisation of the product. Recently, a promising method for solvent detergent treatment of single donor plasma units has been published. Methylene blue light treatment of single donor plasma units has a similar long track record as pooled solvent detergent treated plasma; but the method is less well documented and affects coagulation factor activity more. Psoralen light treated plasma has only recently been introduced (CE marked in Europe

  12. Components of Co-creation

    DEFF Research Database (Denmark)

    Tanev, Stoyan

    2009-01-01

    , such an approach misses the advantages of an empirically driven quantitative approach that benefits from larger size samples and is more appropriate for theory building through the development and testing of hypotheses. It is important, therefore, to seek the development of a research methodology that combines...... the benefits of both qualitative and quantitative research approaches for studying the nature of value co-creation. The article provides a first attempt to identify the main research steps of such a methodology. It provides some preliminary results on the key components of value co-creation between firms...... the inner logic of the value co-creation phenomenon as well as the nature of the results reported in this article. The specific nature of the results was found to be suitable for the application of small-N techniques such as the Qualitative Comparative Analysis (QCA) technique which combines the advantages...

  13. The magnet components database system

    International Nuclear Information System (INIS)

    Baggett, M.J.; Leedy, R.; Saltmarsh, C.; Tompkins, J.C.

    1990-01-01

    The philosophy, structure, and usage MagCom, the SSC magnet components database, are described. The database has been implemented in Sybase (a powerful relational database management system) on a UNIX-based workstation at the Superconducting Super Collider Laboratory (SSCL); magnet project collaborators can access the database via network connections. The database was designed to contain the specifications and measured values of important properties for major materials, plus configuration information (specifying which individual items were used in each cable, coil, and magnet) and the test results on completed magnets. These data will facilitate the tracking and control of the production process as well as the correlation of magnet performance with the properties of its constituents. 3 refs., 10 figs

  14. RCM and component evaluation logic

    International Nuclear Information System (INIS)

    Davis, B.; Anderson, J.

    1991-01-01

    This paper reports on the prevention maintenance program at Palo Verde Nuclear Generating Station (PVNGS), initially developed based on recommendations found in vendor technical manuals and accepted industry standards. The method was used until there was sufficient operating history to justify changes. The Reliability Centered Maintenance (RCM) project was started to provide another approach to the implementation of preventive maintenance. RCM evaluations were performed on nine systems. RCM was then suspended since it was found during implementation that additional documentation was necessary. RCM was selected as a preventive maintenance development process because it provides a documented analytical approach to establishing a preventive maintenance program. It is also being developed throughout the industry as a standard approach to preventive maintenance. PVNGS became interested in performing RCM analyses primarily to ensure that system and component reliability is maintained at the highest level possible and that hidden or rare failures are addressed by appropriate and effective maintenance. A secondary reason was to save maintenance expenditures

  15. Lubrication of nuclear reactor components

    International Nuclear Information System (INIS)

    Wild, E.; Mack, K.J.

    1978-01-01

    Safe operation of liquid metal cooled nuclear reactors requires a knowledge of the tribological behaviour of contacting components at high temperatures with slow relative movement at high frictional loads in a chemically aggressive environment. Experiments have been performed on various material combinations in liquid sodium and argon. Because of the small sliding movements, hydrodynamic lubrication is not expected and thus surface finish is an important factor. Tests have been performed on brushed, ground and lapped surfaces. Among the material combinations tested a CrC-coating on a 1.4961 stainless steel substrate performed well. Friction coefficients of 0.35-0.5 in argon and 0.1-1.2 in liquid sodium were recorded. (author)

  16. On Bayesian Principal Component Analysis

    Czech Academy of Sciences Publication Activity Database

    Šmídl, Václav; Quinn, A.

    2007-01-01

    Roč. 51, č. 9 (2007), s. 4101-4123 ISSN 0167-9473 R&D Projects: GA MŠk(CZ) 1M0572 Institutional research plan: CEZ:AV0Z10750506 Keywords : Principal component analysis ( PCA ) * Variational bayes (VB) * von-Mises–Fisher distribution Subject RIV: BC - Control Systems Theory Impact factor: 1.029, year: 2007 http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V8V-4MYD60N-6&_user=10&_coverDate=05%2F15%2F2007&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=b8ea629d48df926fe18f9e5724c9003a

  17. Functional Generalized Structured Component Analysis.

    Science.gov (United States)

    Suk, Hye Won; Hwang, Heungsun

    2016-12-01

    An extension of Generalized Structured Component Analysis (GSCA), called Functional GSCA, is proposed to analyze functional data that are considered to arise from an underlying smooth curve varying over time or other continua. GSCA has been geared for the analysis of multivariate data. Accordingly, it cannot deal with functional data that often involve different measurement occasions across participants and a large number of measurement occasions that exceed the number of participants. Functional GSCA addresses these issues by integrating GSCA with spline basis function expansions that represent infinite-dimensional curves onto a finite-dimensional space. For parameter estimation, functional GSCA minimizes a penalized least squares criterion by using an alternating penalized least squares estimation algorithm. The usefulness of functional GSCA is illustrated with gait data.

  18. Component codification and identification systems

    International Nuclear Information System (INIS)

    Pannenbaecker, K.

    1977-01-01

    The lecture covers the codification in power stations during the erection phase and commercial operation phase. A diagram gives a survey. There are three basic-codifications for application; 1) Kraftwerk-Kennzeichen-System (KKS) for marking each component in orientated systems, for marking electrical orientated positions in cubicals, switch gears etc. and for marking rooms in buildings; 2) Ordnungssystem (OS) for cost calculation and ordering; 3) Unterlagenarten-Schluessel (UAS) for letters, reports etc. and for documentation. The OS is developed on the principle of cost account number and is therefore close to the organization of each supplier and his special form of design and constrution. KKS has only to mark hardware. Therefore all German owners, consultants, authorities and suppliers develop KKS together and conform to it in DIN 407119. (ORU) [de

  19. The magnet components database system

    International Nuclear Information System (INIS)

    Baggett, M.J.; Leedy, R.; Saltmarsh, C.; Tompkins, J.C.

    1990-01-01

    The philosophy, structure, and usage of MagCom, the SSC magnet components database, are described. The database has been implemented in Sybase (a powerful relational database management system) on a UNIX-based workstation at the Superconducting Super Collider Laboratory (SSCL); magnet project collaborators can access the database via network connections. The database was designed to contain the specifications and measured values of important properties for major materials, plus configuration information (specifying which individual items were used in each cable, coil, and magnet) and the test results on completed magnets. The data will facilitate the tracking and control of the production process as well as the correlation of magnet performance with the properties of its constituents. 3 refs., 9 figs

  20. The genetic component of preeclampsia

    DEFF Research Database (Denmark)

    Hansen, Anette Tarp; Bernth Jensen, Jens Magnus; Hvas, Anne-Mette

    2018-01-01

    Preeclampsia is a major cause of maternal and perinatal deaths. The aetiology of preeclampsia is largely unknown but a polygenetic component is assumed. To explore this hypothesis, we performed an in-depth whole-exome sequencing study in women with (cases, N = 50) and without (controls, N = 50......) preeclampsia. The women were identified in an unselected cohort of 2,545 pregnant women based on data from the Danish National Patient Registry and the Medical Birth Registry. Matching DNA was obtained from a biobank containing excess blood from routine antenatal care visits. Novogene performed the whole......-exome sequencing blinded to preeclampsia status. Variants for comparison between cases and controls were filtered in the Ingenuity Variant Analysis software. We applied two different strategies; a disease association panel approach, which included variants in single genes associated with established clinical risk...

  1. Kinanthropometry - Components of body constitution

    Directory of Open Access Journals (Sweden)

    Maria Tereza Silveira Böhme

    2000-12-01

    Full Text Available The objective of this study is to present the conceptual and historical background to Kinanthropometry and to characterize this area of research. The components of body constitution relating to dimensions, proportions, shape and body composition that should be considered in Physical Education and Sports programs are also described. ARESUMO Este trabalho tem por objetivo apresentar os aspectos conceituais referentes à Cineantropometria, assim como os aspectos históricos e caracterização desta área de estudos. São também descritos os componentes de constituição corporal referentes à dimensões, proporções, forma e composição corporal que devem ser considerados em programas de Educação Física e Esporte.

  2. Structural analysis of nuclear components

    International Nuclear Information System (INIS)

    Ikonen, K.; Hyppoenen, P.; Mikkola, T.; Noro, H.; Raiko, H.; Salminen, P.; Talja, H.

    1983-05-01

    THe report describes the activities accomplished in the project 'Structural Analysis Project of Nuclear Power Plant Components' during the years 1974-1982 in the Nuclear Engineering Laboratory at the Technical Research Centre of Finland. The objective of the project has been to develop Finnish expertise in structural mechanics related to nuclear engineering. The report describes the starting point of the research work, the organization of the project and the research activities on various subareas. Further the work done with computer codes is described and also the problems which the developed expertise has been applied to. Finally, the diploma works, publications and work reports, which are mainly in Finnish, are listed to give a view of the content of the project. (author)

  3. Model reduction by weighted Component Cost Analysis

    Science.gov (United States)

    Kim, Jae H.; Skelton, Robert E.

    1990-01-01

    Component Cost Analysis considers any given system driven by a white noise process as an interconnection of different components, and assigns a metric called 'component cost' to each component. These component costs measure the contribution of each component to a predefined quadratic cost function. A reduced-order model of the given system may be obtained by deleting those components that have the smallest component costs. The theory of Component Cost Analysis is extended to include finite-bandwidth colored noises. The results also apply when actuators have dynamics of their own. Closed-form analytical expressions of component costs are also derived for a mechanical system described by its modal data. This is very useful to compute the modal costs of very high order systems. A numerical example for MINIMAST system is presented.

  4. Library thermohydraulic components for training simulators

    International Nuclear Information System (INIS)

    Castelao Caruana, M. J.; Di Benedetto, A.; Pierini, J.P.

    2013-01-01

    The thermohydraulic components Library was modeled in MatLab/Simulink®. This library owns Pipe type components (pump, control valve and / or heaters), storage tanks (Open, Closed and Equilibrium Water Vapor-Air) and Heat Exchangers (Co-Current, Counter-Current and U-tubes). Each component can be attached to other components through the component library Header, in order to create a more complex thermal-hydraulic system which in turn can interact with other thermal-hydraulic systems. (author)

  5. Precision fiducialization of transport components

    International Nuclear Information System (INIS)

    Fischer, G.E.; Bressler, V.E.; Cobb, J.K.; Jensen, D.R.; Ruland, R.E.; Walz, H.V.; Williams, S.H.

    1992-03-01

    The Final Focus Test Beam (FFTB) is a transport line designed to test both concept and advanced technology for application to future linear colliders. It is currently under construction at SLAC in the central beam line. Most of the quadrupoles of the FFTB have ab initio alignment tolerances of less than 30 microns, if the planned for beam based alignment tuning procedure is to converge. For such placement tolerances to have any meaning requires that the coordinates of the effective centers, seen by the beam particles, be tansferred to tooling (that can be reached by mechanical or optical alignment methods) located on the outside of the components to comparable or better values. We have constructed an apparatus that simultaneously locates to micron tolerances, the effective magnetic center of fussing lenses, as well as the electrical center of beam position monitors (BPM) imbedded therein, and once located, for transferring these coordinates to specially mounted tooling frames that supported the external retroreflectors used in a laser tracker based alignment of the beam line. Details of construction as well as experimental results from the method are presented

  6. Teaching Principal Components Using Correlations.

    Science.gov (United States)

    Westfall, Peter H; Arias, Andrea L; Fulton, Lawrence V

    2017-01-01

    Introducing principal components (PCs) to students is difficult. First, the matrix algebra and mathematical maximization lemmas are daunting, especially for students in the social and behavioral sciences. Second, the standard motivation involving variance maximization subject to unit length constraint does not directly connect to the "variance explained" interpretation. Third, the unit length and uncorrelatedness constraints of the standard motivation do not allow re-scaling or oblique rotations, which are common in practice. Instead, we propose to motivate the subject in terms of optimizing (weighted) average proportions of variance explained in the original variables; this approach may be more intuitive, and hence easier to understand because it links directly to the familiar "R-squared" statistic. It also removes the need for unit length and uncorrelatedness constraints, provides a direct interpretation of "variance explained," and provides a direct answer to the question of whether to use covariance-based or correlation-based PCs. Furthermore, the presentation can be made without matrix algebra or optimization proofs. Modern tools from data science, including heat maps and text mining, provide further help in the interpretation and application of PCs; examples are given. Together, these techniques may be used to revise currently used methods for teaching and learning PCs in the behavioral sciences.

  7. Molecular Components of Catalytic Selectivity

    Energy Technology Data Exchange (ETDEWEB)

    Somorjai, Gabor A.; Park, Jeong Y.

    2008-07-02

    Selectivity, that is, to produce one molecule out of many other thermodynamically feasible product molecules, is the key concept to develop 'clean manufacturing' processes that do not produce byproducts (green chemistry). Small differences in potential energy barriers for elementary reaction steps control which reaction channel is more likely to yield the desired product molecule (selectivity), instead of the overall activation energy for the reaction that controls turnover rates (activity). Recent studies have demonstrated the atomic- or molecular-level tailoring of parameters such as the surface structures of active sites that give rise to nanoparticle size and shape dependence of turnover rates and reaction selectivities. Here, we highlight seven molecular components that influence reaction selectivities. These include: surface structure, adsorbate-induced restructuring, adsorbate mobility, reaction intermediates, surface composition, charge transport, and oxidation states for model metal single crystal and colloid nanoparticle catalysts. We show examples of their functioning and describe in-situ instruments that permit us to investigate their roles in surface reactions.

  8. MICROFLUIDIC COMPONENT CAPABLE OF SELF-SEALING

    DEFF Research Database (Denmark)

    2009-01-01

    A microfluidic component (100) for building a microfluidic system is provided. The microfluidic component (100) can be mounted on a microf luidic breadboard (202) in a manner that allows it to be connected to other microfluidic components (204, 206) without the requirement of additional devices....... The microfluidic component (100) comprises at least one flexible tube piece (102) for transporting a fluid. The microfluidic component (100) also comprises means for applying and maintaining pressure (104) between the flexible tube piece (102) and a tube piece (208, 210) housed in another microfluidic component...

  9. Stochastic Modeling Of Wind Turbine Drivetrain Components

    DEFF Research Database (Denmark)

    Rafsanjani, Hesam Mirzaei; Sørensen, John Dalsgaard

    2014-01-01

    reliable components are needed for wind turbine. In this paper focus is on reliability of critical components in drivetrain such as bearings and shafts. High failure rates of these components imply a need for more reliable components. To estimate the reliability of these components, stochastic models...... are needed for initial defects and damage accumulation. In this paper, stochastic models are formulated considering some of the failure modes observed in these components. The models are based on theoretical considerations, manufacturing uncertainties, size effects of different scales. It is illustrated how...

  10. Nondestructive Characterization of Aged Components

    Energy Technology Data Exchange (ETDEWEB)

    Panetta, Paul D.; Toloczko, Mychailo B.; Garner, Francis A.; Balachov, Iouri I.

    2003-10-21

    It is known that high energy radiation can have numerous effects on materials. In metals and alloys, the effects include, but may not be limited to, mechanical property changes, physical property changes, compositional changes, phase changes, and dimensional changes. Metals and alloys which undergo high energy self-irradiation are also susceptible to these changes. One of the greatest concerns with irradiation of materials is the phenomenon of void swelling which has been observed in a wide variety of metals and alloys. Irradiation causes the formation of a high concentration point defects and microclusters of vacancies and interstitials. With the assistance of an inert atom such as helium, the vacancy-type defects can coalesce to form a stable bubble. This bubble will continue to grow through the net absorption of more vacancy-type defects and helium atoms, and upon reaching a certain critical size, the bubble will begin to grow at an accelerated rate without the assistance of inert atom absorption. The bubble is then said to be an unstably growing void. Depending on the alloy system and environment, swelling values can reach in excess of 50% !V/Vo where Vo is the initial volume of the material. Along with dimensional changes resulting from the formation of bubbles and voids comes changes in the macroscopically observed speed of sound, moduli, electrical resistivity, yield strength, and other properties. These effects can be detrimental to the designed operation of the aged components. In situations where irradiation has sufficient time to cause degradation to materials used in critical applications such as nuclear reactor core structural materials, it is advisable to regularly survey the material properties. It is common practice to use surveillance specimens, but this is not always possible. When surveillance materials are not available, other means for surveying the material properties must be utilized. Sometimes it is possible to core out a small sample which

  11. Hydride embrittlement in zircaloy components

    Energy Technology Data Exchange (ETDEWEB)

    Lobo, Raquel M.; Andrade, Arnaldo H.P.; Castagnet, Mariano, E-mail: rmlobo@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    Zirconium alloys are used in nuclear reactor cores under high-temperature water environment. During service, hydrogen is generated by corrosion processes, and it is readily absorbed by these materials. When hydrogen concentration exceeds the terminal solid solubility, the excess hydrogen precipitates as zirconium hydride (ZrH{sub 2}) platelets or needles. Zirconium alloys components can fail by hydride cracking if they contain large flaws and are highly stressed. Zirconium alloys are susceptible to a mechanism for crack initiation and propagation termed delayed hydride cracking (DHC). The presence of brittle hydrides, with a K{sub Ic} fracture toughness of only a few MPa{radical}m, results in a severe loss in ductility and toughness when platelet normal is oriented parallel to the applied stress. In plate or tubing, hydrides tend to form perpendicular to the thickness direction due to the texture developed during fabrication. Hydrides in this orientation do not generally cause structural problems because applied stresses in the through-thickness direction are very low. However, the high mobility of hydrogen in a zirconium lattice enables redistribution of hydrides normal to the applied stress direction, which can result in localized embrittlement. When a platelet reaches a critical length it ruptures. If the tensile stress is sufficiently great, crack initiation starts at some of these hydrides. Crack propagation occurs by repeating the same process at the crack tip. Delayed hydride cracking can degrade the structural integrity of zirconium alloys during reactor service. The paper focuses on the fracture mechanics and fractographic aspects of hydride material. (author)

  12. CoC Awards by Program Component

    Data.gov (United States)

    Department of Housing and Urban Development — CoC Awards by Program Component reports provide snapshots of award data broken down by eligible program component types for the year selected. The reports, which can...

  13. 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.

  14. A component-based groupware development methodology

    NARCIS (Netherlands)

    Guareis de farias, Cléver; Ferreira Pires, Luis; van Sinderen, Marten J.

    2000-01-01

    Software development in general and groupware applications in particular can greatly benefit from the reusability and interoperability aspects associated with software components. Component-based software development enables the construction of software artefacts by assembling prefabricated,

  15. Cooling system for auxiliary reactor component

    International Nuclear Information System (INIS)

    Fujihira, Tomoko.

    1991-01-01

    A cooling system for auxiliary reactor components comprises three systems, that is, two systems of reactor component cooling water systems (RCCW systems) and a high pressure component cooling water system (HPCCW system). Connecting pipelines having partition valves are intervened each in a cooling water supply pipeline to an emmergency component of each of the RCCW systems, a cooling water return pipeline from the emmergency component of each of the RCCW systems, a cooling water supply pipeline to each of the emmergency components of one of the RCCW system and the HPCCW system and a cooling water return pipeline from each of the emmergency components of one of the RCCW system and the HPCCW system. With such constitution, cooling water can be supplied also to the emmergency components in the stand-by system upon periodical inspection or ISI, thereby enabling to improve the backup performance of the emmergency cooling system. (I.N.)

  16. Aspects for Run-time Component Integration

    DEFF Research Database (Denmark)

    Truyen, Eddy; Jørgensen, Bo Nørregaard; Joosen, Wouter

    2000-01-01

    Component framework technology has become the cornerstone of building a family of systems and applications. A component framework defines a generic architecture into which specialized components can be plugged. As such, the component framework leverages the glue that connects the different inserted...... to dynamically integrate into the architecture of middleware systems new services that support non-functional aspects such as security, transactions, real-time....

  17. Fabrication of ion source components by electroforming

    International Nuclear Information System (INIS)

    Schechter, D.E.; Sluss, F.

    1983-01-01

    Several components of the Oak Ridge National Laboratory (ORNL)/Magnetic Fusion Test Facility (MFTF-B) ion source have been fabricated utilizing an electroforming process. A procedure has been developed for enclosing coolant passages in copper components by electrodepositing a thick (greater than or equal to 0.75-mm) layer of copper (electroforming) over the top of grooves machined into the copper component base. Details of the procedure to fabricate acceleration grids and other ion source components are presented

  18. Development of standard components for remote handling

    International Nuclear Information System (INIS)

    Taguchi, Kou; Kakudate, Satoshi; Nakahira, Masataka; Ito, Akira

    1998-01-01

    The core of Fusion Experimental Reactor consists of various components such as superconducting magnets and forced-cooled in-vessel components, which are remotely maintained due to intense of gamma radiation. Mechanical connectors such as cooling pipe connections, insulation joints and electrical connectors are commonly used for maintenance of these components and have to be standardized in terms of remote handling. This paper describes these mechanical connectors developed as the standard component compatible with remote handling and tolerable for radiation. (author)

  19. Development of standard components for remote handling

    Energy Technology Data Exchange (ETDEWEB)

    Taguchi, Kou; Kakudate, Satoshi; Nakahira, Masataka; Ito, Akira [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-04-01

    The core of Fusion Experimental Reactor consists of various components such as superconducting magnets and forced-cooled in-vessel components, which are remotely maintained due to intense of gamma radiation. Mechanical connectors such as cooling pipe connections, insulation joints and electrical connectors are commonly used for maintenance of these components and have to be standardized in terms of remote handling. This paper describes these mechanical connectors developed as the standard component compatible with remote handling and tolerable for radiation. (author)

  20. Modelization of cooling system components

    Energy Technology Data Exchange (ETDEWEB)

    Copete, Monica; Ortega, Silvia; Vaquero, Jose Carlos; Cervantes, Eva [Westinghouse Electric (Spain)

    2010-07-01

    In the site evaluation study for licensing a new nuclear power facility, the criteria involved could be grouped in health and safety, environment, socio-economics, engineering and cost-related. These encompass different aspects such as geology, seismology, cooling system requirements, weather conditions, flooding, population, and so on. The selection of the cooling system is function of different parameters as the gross electrical output, energy consumption, available area for cooling system components, environmental conditions, water consumption, and others. Moreover, in recent years, extreme environmental conditions have been experienced and stringent water availability limits have affected water use permits. Therefore, modifications or alternatives of current cooling system designs and operation are required as well as analyses of the different possibilities of cooling systems to optimize energy production taking into account water consumption among other important variables. There are two basic cooling system configurations: - Once-through or Open-cycle; - Recirculating or Closed-cycle. In a once-through cooling system (or open-cycle), water from an external water sources passes through the steam cycle condenser and is then returned to the source at a higher temperature with some level of contaminants. To minimize the thermal impact to the water source, a cooling tower may be added in a once-through system to allow air cooling of the water (with associated losses on site due to evaporation) prior to returning the water to its source. This system has a high thermal efficiency, and its operating and capital costs are very low. So, from an economical point of view, the open-cycle is preferred to closed-cycle system, especially if there are no water limitations or environmental restrictions. In a recirculating system (or closed-cycle), cooling water exits the condenser, goes through a fixed heat sink, and is then returned to the condenser. This configuration

  1. Blind Detection of Independent Dynamic Components

    DEFF Research Database (Denmark)

    Hansen, Lars Kai; Larsen, Jan; Kolenda, Thomas

    2001-01-01

    In certain applications of independent component analysis (ICA) it is of interest to test hypotheses concerning the number of components or simply to test whether a given number of components is significant relative to a "white noise" null hypothesis. We estimate probabilities of such competing h...

  2. Method of nickel-plating large components

    International Nuclear Information System (INIS)

    Wilbuer, K.

    1997-01-01

    The invention concerns a method of nickel-plating components, according to which even large components can be provided with an adequate layer of nickel which is pore- and stress-free and such that water is not lost. According to the invention, the component is heated and, after heating, is pickled, rinsed, scoured, plated in an electrolysis process, and rinsed again. (author)

  3. Component failure data base of TRIGA reactors

    International Nuclear Information System (INIS)

    Djuricic, M.

    2004-10-01

    This compilation provides failure data such as first criticality, component type description (reactor component, population, cumulative calendar time, cumulative operating time, demands, failure mode, failures, failure rate, failure probability) and specific information on each type of component of TRIGA Mark-II reactors in Austria, Bangladesh, Germany, Finland, Indonesia, Italy, Indonesia, Slovenia and Romania. (nevyjel)

  4. Component reliability criticality or importance metrics for systems with degrading components

    NARCIS (Netherlands)

    Peng, H.; Coit, D.W.; Feng, Q.

    2012-01-01

    This paper proposes two new importance measures: one new importance measure for systems with -independent degrading components, and another one for systems with -correlated degrading components. Importance measures in previous research are inadequate for systems with degrading components because

  5. Philosophy of integrity assessment of engineering components

    International Nuclear Information System (INIS)

    Chaudhuri, Satyabrata

    2008-01-01

    Integrity assessment of engineering components in power plants and process industries has attracted global attention from the viewpoint of safety and economy for their optimum utilization. This paper describes some aspects of philosophy of component integrity such as life assessment technology, materials used and the factors limiting the serviceability of the components operating at high temperatures and pressures. Numerous investigations have been carried out all over the world to study changes in microstructure and material property due to prolonged service of the components to decide their further serviceability. This paper includes case studies on integrity assessment of service-exposed components carried out in our laboratory as well

  6. Principal component regression analysis with SPSS.

    Science.gov (United States)

    Liu, R X; Kuang, J; Gong, Q; Hou, X L

    2003-06-01

    The paper introduces all indices of multicollinearity diagnoses, the basic principle of principal component regression and determination of 'best' equation method. The paper uses an example to describe how to do principal component regression analysis with SPSS 10.0: including all calculating processes of the principal component regression and all operations of linear regression, factor analysis, descriptives, compute variable and bivariate correlations procedures in SPSS 10.0. The principal component regression analysis can be used to overcome disturbance of the multicollinearity. The simplified, speeded up and accurate statistical effect is reached through the principal component regression analysis with SPSS.

  7. Method of using infrared radiation for assembling a first component with a second component

    Science.gov (United States)

    Sikka, Vinod K.; Whitson, Barry G.; Blue, Craig A.

    1999-01-01

    A method of assembling a first component for assembly with a second component involves a heating device which includes an enclosure having a cavity for inserting a first component. An array of infrared energy generators is disposed within the enclosure. At least a portion of the first component is inserted into the cavity, exposed to infrared energy and thereby heated to a temperature wherein the portion of the first component is sufficiently softened and/or expanded for assembly with a second component.

  8. Repair process and a repaired component

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, III, Herbert Chidsey; Simpson, Stanley F.

    2018-02-20

    Matrix composite component repair processes are disclosed. The matrix composite repair process includes applying a repair material to a matrix composite component, securing the repair material to the matrix composite component with an external securing mechanism and curing the repair material to bond the repair material to the matrix composite component during the securing by the external securing mechanism. The matrix composite component is selected from the group consisting of a ceramic matrix composite, a polymer matrix composite, and a metal matrix composite. In another embodiment, the repair process includes applying a partially-cured repair material to a matrix composite component, and curing the repair material to bond the repair material to the matrix composite component, an external securing mechanism securing the repair material throughout a curing period, In another embodiment, the external securing mechanism is consumed or decomposed during the repair process.

  9. The artifacts of component-based development

    International Nuclear Information System (INIS)

    Rizwan, M.; Qureshi, J.; Hayat, S.A.

    2007-01-01

    Component based development idea was floated in a conference name Mass Produced Software Components in 1968 (1). Since then engineering and scientific libraries are developed to reuse the previously developed functions. This concept is now widely used in SW development as component based development (CBD). Component-based software engineering (CBSE) is used to develop/ assemble software from existing components (2). Software developed using components is called component where (3). This paper presents different architectures of CBD such as Active X, common object request broker architecture (CORBA), remote method invocation (RMI) and simple object access protocol (SOAP). The overall objective of this paper is to support the practice of CBD by comparing its advantages and disadvantages. This paper also evaluates object oriented process model to adapt it for CBD. (author)

  10. VIRTUAL ELECTRONIC COMPONENTS OF THE ELECTRONIC EQUIPMENT

    Directory of Open Access Journals (Sweden)

    E. Lazarevich

    2013-01-01

    Full Text Available The article is present new idea of the creation, developments and improvements of the electronic equipment of complex systems by means of the virtual electronic components. The idea of the virtual electronic components is a presentation and perception of the creation and developments of the equipment on two forming: real – in the manner of standard marketed block of the intellectual property and image – in the manner of virtual component. The real component in most cases slows the development of the electronic equipment. The imaginary component is the «locomotive» of development of the electronic equipment. The Imaginary component contains the scientific has brushed against developer. The scientific has brushed against developer reveals of itself in the manner of virtual component on the modern level of the design rates of microelectronics.

  11. Analyser Framework to Verify Software Components

    Directory of Open Access Journals (Sweden)

    Rolf Andreas Rasenack

    2009-01-01

    Full Text Available Today, it is important for software companies to build software systems in a short time-interval, to reduce costs and to have a good market position. Therefore well organized and systematic development approaches are required. Reusing software components, which are well tested, can be a good solution to develop software applications in effective manner. The reuse of software components is less expensive and less time consuming than a development from scratch. But it is dangerous to think that software components can be match together without any problems. Software components itself are well tested, of course, but even if they composed together problems occur. Most problems are based on interaction respectively communication. Avoiding such errors a framework has to be developed for analysing software components. That framework determines the compatibility of corresponding software components. The promising approach discussed here, presents a novel technique for analysing software components by applying an Abstract Syntax Language Tree (ASLT. A supportive environment will be designed that checks the compatibility of black-box software components. This article is concerned to the question how can be coupled software components verified by using an analyzer framework and determines the usage of the ASLT. Black-box Software Components and Abstract Syntax Language Tree are the basis for developing the proposed framework and are discussed here to provide the background knowledge. The practical implementation of this framework is discussed and shows the result by using a test environment.

  12. Component framework support for developing device drivers

    OpenAIRE

    Michiels, Sam; Kenens, Peter; Matthijs, Frank; Walravens, Dirk; Berbers, Yolande; Verbaeten, Pierre

    2000-01-01

    In this paper, we advocate the use of component framework technology for developing state-of-the-art system software. Relevant contributions of DiPS (Distrinet Protocol Stack), a component framework, include its anonymous interaction model, connectors for handling non-functional issues such as the concurrency model, and builder support. DiPS has effectively been used in industrial protocol stacks. This paper shows how we are using the DiPS component framework to build and support flexib...

  13. Shaking table testing of mechanical components

    International Nuclear Information System (INIS)

    Jurukovski, D.; Taskov, Lj.; Mamucevski, D.; Petrovski, D.

    1995-01-01

    Presented is the experience of the Institute of Earthquake Engineering and Engineering Seismology, Skopje, Republic of Macedonia in seismic qualification of mechanical components by shaking table testing. Technical data and characteristics for the three shaking tables available at the Institute are given. Also, for characteristic mechanical components tested at the Institute laboratories, basic data such as producer, testing investor, description of the component, testing regulation, testing equipment and final user of the results. (author)

  14. Environmental variation partitioned into separate heritable components

    DEFF Research Database (Denmark)

    Ørsted, Michael; Rohde, Palle Duun; Hoffmann, Ary A

    2018-01-01

    Trait variation is normally separated into genetic and environmental components, yet genetic factors also control the expression of environmental variation, encompassing plasticity across environmental gradients and within-environment responses. We defined four components of environmental variation......: plasticity across environments, variability in plasticity, variation within environments, and differences in within-environment variation across environments. We assessed these components for cold tolerance across five rearing temperatures using the Drosophila melanogaster Genetic Reference Panel (DGRP...

  15. Epistemic uncertainties when estimating component failure rate

    International Nuclear Information System (INIS)

    Jordan Cizelj, R.; Mavko, B.; Kljenak, I.

    2000-01-01

    A method for specific estimation of a component failure rate, based on specific quantitative and qualitative data other than component failures, was developed and is described in the proposed paper. The basis of the method is the Bayesian updating procedure. A prior distribution is selected from a generic database, whereas likelihood is built using fuzzy logic theory. With the proposed method, the component failure rate estimation is based on a much larger quantity of information compared to the presently used classical methods. Consequently, epistemic uncertainties, which are caused by lack of knowledge about a component or phenomenon are reduced. (author)

  16. Fracture of an uncemented tantalum patellar component

    Directory of Open Access Journals (Sweden)

    Nathan L. Grimm, MD

    2016-06-01

    Full Text Available A 62-year-old man presented with the acute, atraumatic onset of pain 3 years after uncemented right total knee arthroplasty. He complained of new mechanical locking with the knee held in extension on examination and unable to flex the knee. On the plain radiographs, the patellar component peg was fractured and the plate was dislocated. The knee was immobilized, and revision to a cemented 3-peg component was performed. Fracture of a single-peg, tantalum-backed uncemented patellar component has not been described. Clinical suspicion for this should be given in the setting of acute locking. We recommend revision with a cemented polyethylene component.

  17. SOFA 2 Component Framework and Its Ecosystem

    Czech Academy of Sciences Publication Activity Database

    Malohlava, M.; Hnětynka, P.; Bureš, Tomáš

    2013-01-01

    Roč. 295, 9 May (2013), s. 101-106 ISSN 1571-0661. [FESCA 2012. International Workshop on Formal Engineering approaches to Software Components and Architectures /9./. Tallinn, 31.03.2012] R&D Projects: GA ČR GD201/09/H057 Grant - others:GA AV ČR(CZ) GAP202/11/0312; UK(CZ) SVV-2012-265312 Keywords : CBSE * component system * component model * component * sofa * ecosystem * development tool Subject RIV: JC - Computer Hardware ; Software

  18. Compatibility and testing of electronic components

    CERN Document Server

    Jowett, C E

    2013-01-01

    Compatibility and Testing of Electronic Components outlines the concepts of component part life according to thresholds of failure; the advantages that result from identifying such thresholds; their identification; and the various tests used in their detection. The book covers topics such as the interconnection of miniature passive components; the integrated circuit compatibility and its components; the semiconductor joining techniques; and the thin film hybrid approach in integrated circuits. Also covered are topics such as thick film resistors, conductors, and insulators; thin inlays for el

  19. Thermogravimetric analysis of combustible waste components

    DEFF Research Database (Denmark)

    Munther, Anette; Wu, Hao; Glarborg, Peter

    In order to gain fundamental knowledge about the co-combustion of coal and waste derived fuels, the pyrolytic behaviors of coal, four typical waste components and their mixtures have been studied by a simultaneous thermal analyzer (STA). The investigated waste components were wood, paper, polypro......In order to gain fundamental knowledge about the co-combustion of coal and waste derived fuels, the pyrolytic behaviors of coal, four typical waste components and their mixtures have been studied by a simultaneous thermal analyzer (STA). The investigated waste components were wood, paper...

  20. Modulation of capillary condensation by trace component

    Directory of Open Access Journals (Sweden)

    Shiqi Zhou

    2011-06-01

    Full Text Available Impact of trace component on capillary condensation (CC is investigated systematically using a classical density functional theory. It is discovered that (i presence of the trace component makes the CC to occur at much lower condensation pressure than when its absence; (ii Lennard-Jones potential parameters like size parameter and energy parameter of the trace component, and its concentration in the bulk adsorption system, show their effects the most remarkably within a particular range beyond which the effects eventually become insignificant. The present discoveries have implications in low pressure storage of gases, separation and enrichment of low concentration component, and easy control of CC transition, etc.

  1. Power electronics handbook components, circuits and applications

    CERN Document Server

    Mazda, F F

    1993-01-01

    Power Electronics Handbook: Components, Circuits, and Applications is a collection of materials about power components, circuit design, and applications. Presented in a practical form, theoretical information is given as formulae. The book is divided into three parts. Part 1 deals with the usual components found in power electronics such as semiconductor devices and power semiconductor control components, their electronic compatibility, and protection. Part 2 tackles parts and principles related to circuits such as switches; link frequency chargers; converters; and AC line control, and Part 3

  2. OCSEGen: Open Components and Systems Environment Generator

    Science.gov (United States)

    Tkachuk, Oksana

    2014-01-01

    To analyze a large system, one often needs to break it into smaller components.To analyze a component or unit under analysis, one needs to model its context of execution, called environment, which represents the components with which the unit interacts. Environment generation is a challenging problem, because the environment needs to be general enough to uncover unit errors, yet precise enough to make the analysis tractable. In this paper, we present a tool for automated environment generation for open components and systems. The tool, called OCSEGen, is implemented on top of the Soot framework. We present the tool's current support and discuss its possible future extensions.

  3. Digital Components in Swedish NPP Power Systems

    International Nuclear Information System (INIS)

    Karlsson, Mattias; Eriksson, Tage

    2015-01-01

    Swedish nuclear power plants have over the last 20 years of operation modernised or exchanged several systems and components of the electrical power system. Within these works, new components based on digital technology have been employed in order to realize functionality that was previously achieved by using electro-mechanical or analogue technology. Components and systems such as relay protection, rectifiers, inverters, variable speed drives and diesel-generator sets are today equipped with digital components. Several of the systems and components fulfil functions with a safety-role in the NPP. Recently, however, a number of incidents have occurred which highlight deficiencies in the design or HMI of the equipment, which warrants questions whether there are generic problems with some applications of digital components that needs to be addressed. The use of digital components has presented cost effective solutions, or even the only available solution on the market enabling a modernisation. The vast majority of systems using digital components have been operating without problems and often contribute to improved safety but the challenge of non-detectable, or non-identifiable, failure modes remain. In this paper, the extent to which digital components are used in Swedish NPP power systems will be presented including a description of typical applications. Based on data from maintenance records and fault reports, as well as interviews with designers and maintenance personnel, the main areas where problems have been encountered and where possible risks have been identified will be described. The paper intends to investigate any 'tell-tales' that could give signals of unwanted behaviour. Furthermore, particular benefits experienced by using digital components will be highlighted. The paper will also discuss the safety relevance of these findings and suggest measures to improve safety in the application of digital components in power systems. (authors)

  4. Runtime Concepts of Hierarchical Software Components

    Czech Academy of Sciences Publication Activity Database

    Bureš, Tomáš; Hnětynka, P.; Plášil, František

    2007-01-01

    Roč. 8, special (2007), s. 454-463 ISSN 1525-9293 R&D Projects: GA AV ČR 1ET400300504 Institutional research plan: CEZ:AV0Z10300504 Keywords : component-based development * hierarchical components * connectors * controlers * runtime environment Subject RIV: JC - Computer Hardware ; Software

  5. Pedagogical Support Components of Students' Social Adaptation

    Science.gov (United States)

    Vlasova, Vera K.; Simonova, Galina I.; Soleymani, Nassim

    2016-01-01

    The urgency of the problem stated in the article is caused by the need of pedagogical support of students' social adaptation on the basis of systematicity, which is achieved if we correctly define the components of the process. The aim of the article is to determine the pedagogical support components of students' social adaptation. The leading…

  6. Least-squares variance component estimation

    NARCIS (Netherlands)

    Teunissen, P.J.G.; Amiri-Simkooei, A.R.

    2007-01-01

    Least-squares variance component estimation (LS-VCE) is a simple, flexible and attractive method for the estimation of unknown variance and covariance components. LS-VCE is simple because it is based on the well-known principle of LS; it is flexible because it works with a user-defined weight

  7. Hybrid solar lighting distribution systems and components

    Science.gov (United States)

    Muhs, Jeffrey D [Lenoir City, TN; Earl, Dennis D [Knoxville, TN; Beshears, David L [Knoxville, TN; Maxey, Lonnie C [Powell, TN; Jordan, John K [Oak Ridge, TN; Lind, Randall F [Lenoir City, TN

    2011-07-05

    A hybrid solar lighting distribution system and components having at least one hybrid solar concentrator, at least one fiber receiver, at least one hybrid luminaire, and a light distribution system operably connected to each hybrid solar concentrator and each hybrid luminaire. A controller operates all components.

  8. A framework for sequential multiblock component methods

    NARCIS (Netherlands)

    Smilde, A.K.; Westerhuis, J.A.; Jong, S.de

    2003-01-01

    Multiblock or multiset methods are starting to be used in chemistry and biology to study complex data sets. In chemometrics, sequential multiblock methods are popular; that is, methods that calculate one component at a time and use deflation for finding the next component. In this paper a framework

  9. Systems with randomly failing repairable components

    DEFF Research Database (Denmark)

    Der Kiureghian, Armen; Ditlevsen, Ove Dalager; Song, Junho

    2005-01-01

    Closed-form expressions are derived for the steady-state availability, mean rate of failure, mean duration of downtime and reliability of a general system with randomly and independently failing repairable components. Component failures are assumed to be homogeneous Poisson events in time and rep...

  10. Active components for integrated plasmonic circuits

    DEFF Research Database (Denmark)

    Krasavin, A.V.; Bolger, P.M.; Zayats, A.V.

    2009-01-01

    We present a comprehensive study of highly efficient and compact passive and active components for integrated plasmonic circuit based on dielectric-loaded surface plasmon polariton waveguides.......We present a comprehensive study of highly efficient and compact passive and active components for integrated plasmonic circuit based on dielectric-loaded surface plasmon polariton waveguides....

  11. Radiation dose effects, hardening of electronic components

    International Nuclear Information System (INIS)

    Dupont-Nivet, E.

    1991-01-01

    This course reviews the mechanism of interaction between ionizing radiation and a silicon oxide type dielectric, in particular the effect of electron-hole pairs creation in the material. Then effects of cumulated dose on electronic components and especially in MOS technology are examined. Finally methods hardening of these components are exposed. 93 refs

  12. Trends in chassis and automobile electronics components

    Energy Technology Data Exchange (ETDEWEB)

    Hackenberg, Ulrich [Volkswagen AG, Wolfsburg (Germany)

    2008-07-01

    The rapidly-growing importance of electronics in automobile construction is in part determined by the debate on sustainability and the clear trend towards electric power trains. Another factor, however, is the decisive impact of electronics on the further development of components, e.g. for chassis. Apart from environmental protection, key motivators for component development include comfort, safety, infotainment and driver assistance. (orig.)

  13. Sandia_HighTemperatureComponentEvaluation_2015

    Energy Technology Data Exchange (ETDEWEB)

    Cashion, Avery T. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-03-01

    The objective of this project is to perform independent evaluation of high temperature components to determine their suitability for use in high temperature geothermal tools. Development of high temperature components has been increasing rapidly due to demand from the high temperature oil and gas exploration and aerospace industries. Many of these new components are at the late prototype or first production stage of development and could benefit from third party evaluation of functionality and lifetime at elevated temperatures. In addition to independent testing of new components, this project recognizes that there is a paucity of commercial-off-the-shelf COTS components rated for geothermal temperatures. As such, high-temperature circuit designers often must dedicate considerable time and resources to determine if a component exists that they may be able to knead performance out of to meet their requirements. This project aids tool developers by characterization of select COTS component performances beyond published temperature specifications. The process for selecting components includes public announcements of project intent (e.g., FedBizOps), direct discussions with candidate manufacturers,and coordination with other DOE funded programs.

  14. Insulating jacket for heat sensitive components

    International Nuclear Information System (INIS)

    Class, G.

    1980-01-01

    The insulating jacket for long core components of sodium-cooled reactors consists of several layers of austenitic steel, between which a woven wire mesh of the same material is fitted. It is wound in the form of a spiral bandage on the core component. (DG) [de

  15. Tweaking the Four-Component Model

    Science.gov (United States)

    Curzer, Howard J.

    2014-01-01

    By maintaining that moral functioning depends upon four components (sensitivity, judgment, motivation, and character), the Neo-Kohlbergian account of moral functioning allows for uneven moral development within individuals. However, I argue that the four-component model does not go far enough. I offer a more accurate account of moral functioning…

  16. Sodium removal, storage, and requalification of components

    International Nuclear Information System (INIS)

    Gallegos, A.; Shimazaki, T.; Oliva, R.M.

    1974-01-01

    The objectives of this program are to devise, develop, test, and evaluate techniques for sodium removal and storage of test specimens and components, and to expand and refine, by test and analysis, the sodium removal and storage techniques and procedures for use in processing typical LMFBR components

  17. Emotional stability components of human performance problems

    International Nuclear Information System (INIS)

    Wexler, R.H.

    1987-01-01

    Over half of all significant events that occur in nuclear plants involve human performance problems. There is increasing worldwide recognition that human performance problems have a significant impact on the safety, cost, and efficiency of nuclear plant operations. Emotional stability components have an important direct and indirect impact on human performance problems. This paper examines emotional stability components that are currently incorporated into human performance evaluation systems (HPES) in nuclear plants. It describes HPES programs being developed around the world, the emotional stability components that are currently referred to in these programs, and suggestions for improving HPES programs through a greater understanding of emotion stability components. A review of emotional stability components that may hinder or promote a plant environment that encourages the voluntary reporting and correction of human error is also presented

  18. Passive components used in power converters

    CERN Document Server

    Rufer, A; Barrade, P

    2006-01-01

    In power converters, passive components play an important role, and have in general specific nature and properties. The goal of this tutorial is to give an overview, first on inductive components for power conversion, and second on dedicated power capacitors. In a third part, new components— supercapacitors—will be presented. Generally, inductors for power applications must be custom designed. In this tutorial, the most important effects encountered when realising inductive components will be presented in the first part, without entering into the detailed design of such components. For that purpose, the referenced documents that have served as a base for this tutorial must be consulted [1], [2], and mainly [3]. The second part of this tutorial (Capacitors used in power electronics) is dedicated to power capacitors. Unlike inductors, capacitors cannot be specifically designed, but must be selected from a manufacturer’s list of components. Here, the documentation corresponds to a subset of Ref. [4] that h...

  19. LWR nuclear power plant component failures

    International Nuclear Information System (INIS)

    Schmidt, W.H.

    1980-10-01

    An analysis of the most significant light water reactor (LWR) nuclear power plant component failures, from information in the computerized Nuclear Safety Information Center (NSIC) data bank, shows that for both pressurized water reactor (PWR) and boiling water reactor (BWR) plants the component category most responsible for reactor shutdowns is valves. Next in importance for PWR shutdowns is steam generators followed by seals of all kinds. For BWR plants, seals, and pipes and pipe fittings are the second and third most important component failure categories which lead to reactor shutdown. The data are for records extending from early 1972 through September 1978. A list of the most significant component categories and a breakdown of the number of component citations for both PWR and BWR reactor types are presented

  20. Thermal performance of an innovative roof component

    Energy Technology Data Exchange (ETDEWEB)

    Dimoudi, A. [Department of Environmental Engineering, Democritus University of Thrace, Vassilisis Sofias 12, 67 100 Xanthi (Greece); Lykoudis, S. [Institute for Environmental Research and Sustainable Development, National Observatory of Athens, I. Metaxa and B. Pavlou, 152 36 Penteli (Greece); Androutsopoulos, A. [Buildings Department, Division of Energy Efficiency, Centre for Renewable Energy Sources (CRES), 19th km Marathonos Aven., 190 09 Pikermi (Greece)

    2006-11-15

    In this paper, the thermal performance of a ventilated roof component is investigated during the winter period. The ventilated roof component consists of a conventional roof structure - reinforced concrete with a layer of thermal insulation - an air gap that allows the movement of the ambient air and an external layer made of a prefabricated concrete slab. The experimental results of the ventilated roof component during the winter period are presented and its thermal performance is analysed. The effect of key construction parameters like the height of the air gap and the use of a radiant barrier in the air gap is also investigated. Analysis of the results showed that the performance of a ventilated roof component is comparable to a conventional structure during winter. The ventilated component is shown to be in compliance with Greek regulatory requirements in terms of U-value. (author)

  1. Hot gas path component cooling system

    Science.gov (United States)

    Lacy, Benjamin Paul; Bunker, Ronald Scott; Itzel, Gary Michael

    2014-02-18

    A cooling system for a hot gas path component is disclosed. The cooling system may include a component layer and a cover layer. The component layer may include a first inner surface and a second outer surface. The second outer surface may define a plurality of channels. The component layer may further define a plurality of passages extending generally between the first inner surface and the second outer surface. Each of the plurality of channels may be fluidly connected to at least one of the plurality of passages. The cover layer may be situated adjacent the second outer surface of the component layer. The plurality of passages may be configured to flow a cooling medium to the plurality of channels and provide impingement cooling to the cover layer. The plurality of channels may be configured to flow cooling medium therethrough, cooling the cover layer.

  2. Properties of cold components of symbiotic stars

    International Nuclear Information System (INIS)

    Luud, L.; Leehdyarv, L.

    1986-01-01

    Using the Blackwell-Shallis method the luminosities, temperatures and radii for cold components of symbiotic stars and for a sample of field red giants have been determined by means of infrared photometric observations. It turned out that the cold components of symbiotic stars do not differ from the normal red giants of the asymptotic branch. The masses of cold components of symbiotic stars have been found to be close to 3 M* (M* is the solar mass).The cold components of symbiotic stars do not fill their Roche lobes. About 10 times more carbon stars than the normal value in the vicinity of the Sun have been found among the cold components of symbiotic stars

  3. COPD phenotype description using principal components analysis

    DEFF Research Database (Denmark)

    Roy, Kay; Smith, Jacky; Kolsum, Umme

    2009-01-01

    BACKGROUND: Airway inflammation in COPD can be measured using biomarkers such as induced sputum and Fe(NO). This study set out to explore the heterogeneity of COPD using biomarkers of airway and systemic inflammation and pulmonary function by principal components analysis (PCA). SUBJECTS...... AND METHODS: In 127 COPD patients (mean FEV1 61%), pulmonary function, Fe(NO), plasma CRP and TNF-alpha, sputum differential cell counts and sputum IL8 (pg/ml) were measured. Principal components analysis as well as multivariate analysis was performed. RESULTS: PCA identified four main components (% variance...... associations between the variables within components 1 and 2. CONCLUSION: COPD is a multi dimensional disease. Unrelated components of disease were identified, including neutrophilic airway inflammation which was associated with systemic inflammation, and sputum eosinophils which were related to increased Fe...

  4. Metacognitive components in smart learning environment

    Science.gov (United States)

    Sumadyo, M.; Santoso, H. B.; Sensuse, D. I.

    2018-03-01

    Metacognitive ability in digital-based learning process helps students in achieving learning goals. So that digital-based learning environment should make the metacognitive component as a facility that must be equipped. Smart Learning Environment is the concept of a learning environment that certainly has more advanced components than just a digital learning environment. This study examines the metacognitive component of the smart learning environment to support the learning process. A review of the metacognitive literature was conducted to examine the components involved in metacognitive learning strategies. Review is also conducted on the results of study smart learning environment, ranging from design to context in building smart learning. Metacognitive learning strategies certainly require the support of adaptable, responsive and personalize learning environments in accordance with the principles of smart learning. The current study proposed the role of metacognitive component in smart learning environment, which is useful as the basis of research in building environment in smart learning.

  5. Adaptation of Black-Box Software Components

    Directory of Open Access Journals (Sweden)

    Rolf Andreas Rasenack

    2008-01-01

    Full Text Available The globalization of the software market leads to crucial problems for software companies. More competition between software companies arises and leads to the force on companies to develop ever newer software products in ever shortened time interval. Therefore the time to market for software systems is shortened and obviously the product life cycle is shortened too. Thus software companies shortened the time interval for research and development. Due to the fact of competition between software companies software products have to develop low-priced and this leads to a smaller return on investment. A big challenge for software companies is the use of an effective research and development process to have these problems under control. A way to control these problems can be the reuse of existing software components and adapt those software components to new functionality or accommodate mismatched interfaces. Complete redevelopment of software products is more expensive and time consuming than to develop software components. The approach introduced here presents novel technique together with a supportive environment that enables developers to cope with the adaptability of black-box software components. A supportive environment will be designed that checks the compatibility of black-box software components with the assistance of their specifications. Generated adapter software components can take over the part of adaptation and advance the functionality. Besides, a pool of software components can be used to compose an application to satisfy customer needs. Certainly this pool of software components consists of black-box software components and adapter software components which can be connected on demand.

  6. Composing simulations using persistent software components

    Energy Technology Data Exchange (ETDEWEB)

    Holland, J.V.; Michelsen, R.E.; Powell, D.R.; Upton, S.C.; Thompson, D.R.

    1999-03-01

    The traditional process for developing large-scale simulations is cumbersome, time consuming, costly, and in some cases, inadequate. The topics of software components and component-based software engineering are being explored by software professionals in academic and industrial settings. A component is a well-delineated, relatively independent, and replaceable part of a software system that performs a specific function. Many researchers have addressed the potential to derive a component-based approach to simulations in general, and a few have focused on military simulations in particular. In a component-based approach, functional or logical blocks of the simulation entities are represented as coherent collections of components satisfying explicitly defined interface requirements. A simulation is a top-level aggregate comprised of a collection of components that interact with each other in the context of a simulated environment. A component may represent a simulation artifact, an agent, or any entity that can generated events affecting itself, other simulated entities, or the state of the system. The component-based approach promotes code reuse, contributes to reducing time spent validating or verifying models, and promises to reduce the cost of development while still delivering tailored simulations specific to analysis questions. The Integrated Virtual Environment for Simulation (IVES) is a composition-centered framework to achieve this potential. IVES is a Java implementation of simulation composition concepts developed at Los Alamos National Laboratory for use in several application domains. In this paper, its use in the military domain is demonstrated via the simulation of dismounted infantry in an urban environment.

  7. The Component-Based Application for GAMESS

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Fang [Iowa State Univ., Ames, IA (United States)

    2007-01-01

    GAMESS, a quantum chetnistry program for electronic structure calculations, has been freely shared by high-performance application scientists for over twenty years. It provides a rich set of functionalities and can be run on a variety of parallel platforms through a distributed data interface. While a chemistry computation is sophisticated and hard to develop, the resource sharing among different chemistry packages will accelerate the development of new computations and encourage the cooperation of scientists from universities and laboratories. Common Component Architecture (CCA) offers an enviromnent that allows scientific packages to dynamically interact with each other through components, which enable dynamic coupling of GAMESS with other chetnistry packages, such as MPQC and NWChem. Conceptually, a cotnputation can be constructed with "plug-and-play" components from scientific packages and require more than componentizing functions/subroutines of interest, especially for large-scale scientific packages with a long development history. In this research, we present our efforts to construct cotnponents for GAMESS that conform to the CCA specification. The goal is to enable the fine-grained interoperability between three quantum chemistry programs, GAMESS, MPQC and NWChem, via components. We focus on one of the three packages, GAMESS; delineate the structure of GAMESS computations, followed by our approaches to its component development. Then we use GAMESS as the driver to interoperate integral components from the other tw"o packages, arid show the solutions for interoperability problems along with preliminary results. To justify the versatility of the design, the Tuning and Analysis Utility (TAU) components have been coupled with GAMESS and its components, so that the performance of GAMESS and its components may be analyzed for a wide range of systetn parameters.

  8. Research regarding reverse engineering for aircraft components

    Directory of Open Access Journals (Sweden)

    Udroiu Razvan

    2017-01-01

    Full Text Available Reverse engineering is a useful technique used in manufacturing and design process of new components. In aerospace industry new components can be developed, based on existing components without technical Computer Aided Design (CAD data, in order to reduce the development cycle of new products. This paper proposes a methodology wherein the CAD model of turbine blade can be build using computer aided reverse engineering technique utilising a 5 axis Coordinate Measuring Machine (CMM. The proposed methodology uses a scanning strategy by features, followed by a design methodology for 3D modelling of complex shapes.

  9. Microwave components for cellular portable radiotelephone

    Science.gov (United States)

    Muraguchi, Masahiro; Aikawa, Masayoshi

    1995-09-01

    Mobile and personal communication systems are expected to represent a huge market for microwave components in the coming years. A number of components in silicon bipolar, silicon Bi-CMOS, GaAs MESFET, HBT and HEMT are now becoming available for system application. There are tradeoffs among the competing technologies with regard to performance, cost, reliability and time-to-market. This paper describes process selection and requirements of cost and r.f. performances to microwave semiconductor components for digital cellular and cordless telephones. Furthermore, new circuit techniques which were developed by NTT are presented.

  10. Modular core component support for nuclear reactor

    International Nuclear Information System (INIS)

    Finch, L.M.; Anthony, A.J.

    1975-01-01

    The core of a nuclear reactor is made up of a plurality of support modules for containing components such as fuel elements, reflectors and control rods. Each module includes a component support portion located above a grid plate in a low-pressure coolant zone and a coolant inlet portion disposed within a module receptacle which depends from the grid plate into a zone of high-pressure coolant. Coolant enters the module through aligned openings within the receptacle and module inlet portion and flows upward into contact with the core components. The modules are hydraulically balanced within the receptacles to prevent expulsion by the upward coolant forces. (U.S.)

  11. Ionizing radiations simulation on bipolar components

    International Nuclear Information System (INIS)

    Montagner, X.

    1999-01-01

    This thesis presents the ionizing radiation effects on bipolar components and more specially their behavior facing the total dose. The first part is devoted to the radiation environments with a special attention to the spatial environments and new emergent environments. The specificities of bipolar components are then presented and their behavior facing the interactions. The physical mechanisms bound to the dose rate are also discussed. The second part presents a physical analysis of degradations induced by the cumulated dosimetry on bipolar components and simulation with the ATLAS code. The third part exposes an electric empirical simulation induced by the cumulated dose in static conditions. (A.L.B.)

  12. Component database development for the CBM experiment

    International Nuclear Information System (INIS)

    Akishina, E.P.; Alexandrov, E.I.; Alexandrov, I.N.; Filozova, I.A.; Ivanov, V.V.; Friese, V.

    2015-01-01

    This paper presents the implementation of the component database for the CBM experiment. The considered database is designed to effectively manage a large number of components for different CBM detectors during their manufacture, installation and operation. This database contains information about the production company, quality indicators, including test results, information on the whereabouts of the component and its status. A functional model, a design of the database schema, a description of tables and catalogs as well as a graphical user interface system are shown. [ru

  13. Components of the primary circuit of LWRs

    International Nuclear Information System (INIS)

    1980-01-01

    This standard is to be applied to components made of metallic materials, operated at design temperatures of up to 673 K (400 C). The primary circuit as the pressure containment of the reactor coolant comprises: Reactor pressure vessel (without internals), steam generator (primary loop), pressurizer, reactor coolant pump housing, interconnecting pipings between the components mentioned above and appropriate various valve and instrument casings, pipings branding from the above components and interconnecting pipings, including the appropriate instrument casings, up to and including the first isolating valve, pressure shielding of control rod drives. (orig.) [de

  14. NHI Component Technical Readiness Evaluation System

    International Nuclear Information System (INIS)

    Sherman, S.; Wilson, Dane F.; Pawel, Steven J.

    2007-01-01

    A decision process for evaluating the technical readiness or maturity of components (i.e., heat exchangers, chemical reactors, valves, etc.) for use by the U.S. DOE Nuclear Hydrogen Initiative is described. This system is used by the DOE NHI to assess individual components in relation to their readiness for pilot-scale and larger-scale deployment and to drive the research and development work needed to attain technical maturity. A description of the evaluation system is provided, and examples are given to illustrate how it is used to assist in component R and D decisions.

  15. Thermally activated, single component epoxy systems

    KAUST Repository

    Unruh, David A.

    2011-08-23

    A single component epoxy system in which the resin and hardener components found in many two-component epoxies are combined onto the same molecule is described. The single molecule precursor to the epoxy resin contains both multiple epoxide moieties and a diamine held latent by thermally degradable carbamate linkages. These bis-carbamate "single molecule epoxies" have an essentially infinite shelf life and access a significant range in curing temperatures related to the structure of the carbamate linkages used. © 2011 American Chemical Society.

  16. Realizing spaces as path-component spaces

    OpenAIRE

    Banakh, Taras; Brazas, Jeremy

    2018-01-01

    The path component space of a topological space $X$ is the quotient space $\\pi_0(X)$ whose points are the path components of $X$. We show that every Tychonoff space $X$ is the path-component space of a Tychonoff space $Y$ of weight $w(Y)=w(X)$ such that the natural quotient map $Y\\to \\pi_0(Y)=X$ is a perfect map. Hence, many topological properties of $X$ transfer to $Y$. We apply this result to construct a compact space $X\\subset \\mathbb{R}^3$ for which the fundamental group $\\pi_1(X,x_0)$ is...

  17. Thermally activated, single component epoxy systems

    KAUST Repository

    Unruh, David A.; Pastine, Stefan J.; Moreton, Jessica C.; Frechet, Jean

    2011-01-01

    A single component epoxy system in which the resin and hardener components found in many two-component epoxies are combined onto the same molecule is described. The single molecule precursor to the epoxy resin contains both multiple epoxide moieties and a diamine held latent by thermally degradable carbamate linkages. These bis-carbamate "single molecule epoxies" have an essentially infinite shelf life and access a significant range in curing temperatures related to the structure of the carbamate linkages used. © 2011 American Chemical Society.

  18. Measurements for stresses in machine components

    CERN Document Server

    Yakovlev, V F

    1964-01-01

    Measurements for Stresses in Machine Components focuses on the state of stress and strain of components and members, which determines the service life and strength of machines and structures. This book is divided into four chapters. Chapter I describes the physical basis of several methods of measuring strains, which includes strain gauges, photoelasticity, X-ray diffraction, brittle coatings, and dividing grids. The basic concepts of the electric strain gauge method for measuring stresses inside machine components are covered in Chapter II. Chapter III elaborates on the results of experim

  19. Impedance measurements of components for the ALS

    International Nuclear Information System (INIS)

    Corlett, J.N.; Rimmer, R.A.

    1993-05-01

    The high current and short bunch length of the ALS beam make the machine susceptible to beam instabilities over a frequency range extending to 13 GHz and beyond. All components of the storage ring have been carefully designed to minimize the impedance presented to the beam, and assemblies have been laid out to avoid resonant enclosures between components. Novel bellows shields allowing considerable mechanical movement while maintaining a low impedance are described. Results are presented of impedance measurements of ALS components and assemblies of components, using a precision coaxial wire technique in frequency domain, extending to frequencies beyond cut-off. All measurements were performed at the Lambertson Beam Electrodynamics Laboratory of the Center for Beam Physics at LBL

  20. Transforming the Reserve Component: Four Essays

    National Research Council Canada - National Science Library

    Binnendijk, Hans; Baranick, Michael J; Bell, Raymond E., Jr; Cordero, Gina; Duncan, Stephen M; Holshek, Christopher; Wentz, Larry

    2005-01-01

    This volume contains four essays on various aspects of the Reserve Component. We publish it at a time when Reserves are serving overseas at historically high rates and when new missions like homeland security demand their attention...

  1. Transforming the Reserve Component: Four Essays

    National Research Council Canada - National Science Library

    Binnendijk, Hans; Baranick, Michael J; Bell, Raymond E., Jr; Cordero, Gina; Duncan, Stephen M; Holshek, Christopher; Wentz, Larry

    2005-01-01

    .... The first essay calls for a fundamental restructuring of the Reserve Component in light of the largest mobilization since the Korean War, which has been fraught with problems in terms of combat...

  2. Recommendations for the use of irradiated components

    International Nuclear Information System (INIS)

    2007-01-01

    The disease 'graft-versus-host' associated with the transfusion (EIVH TA) is an adverse reaction rare but fatal, linked to the proliferation of T cells that are found in cellular components and reacting against the receptor's tissues). Gamma irradiation of cellular components is used as a prevention method because it deactivates the lymphocytes T by reducing its survival and by restraining its proliferation without producing alterations in others cells function. Recommendations for the use of gamma irradiation along with clinical indications for pediatric patients, patients with acquired immunosuppression and immunocompetent patients are given in this study. A brief description of operative aspects of irradiation procedures such as components to be irradiated, irradiation method, irradiation dose and viability of irradiated components is given [es

  3. Travelling cranes for heavy reactor component handling

    International Nuclear Information System (INIS)

    Champeil, M.

    1977-01-01

    Structure and operating machinery of two travelling cranes (600 t and 450 t) used in the Framatome factory for handling heavy reactor components are described. When coupled, these cranes can lift loads up to 1000 t [fr

  4. Manufacture of components for Canadian reactor programs

    International Nuclear Information System (INIS)

    Perry, L.P.

    Design features, especially those relating to calandrias, are pointed out for many CANDU-type reactors and the Taiwan research reactor. The special requirements shouldered by the Canadian suppliers of heavy reactor components are analyzed. (E.C.B.)

  5. Analysis Method for Integrating Components of Product

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jun Ho [Inzest Co. Ltd, Seoul (Korea, Republic of); Lee, Kun Sang [Kookmin Univ., Seoul (Korea, Republic of)

    2017-04-15

    This paper presents some of the methods used to incorporate the parts constituting a product. A new relation function concept and its structure are introduced to analyze the relationships of component parts. This relation function has three types of information, which can be used to establish a relation function structure. The relation function structure of the analysis criteria was established to analyze and present the data. The priority components determined by the analysis criteria can be integrated. The analysis criteria were divided based on their number and orientation, as well as their direct or indirect characteristic feature. This paper presents a design algorithm for component integration. This algorithm was applied to actual products, and the components inside the product were integrated. Therefore, the proposed algorithm was used to conduct research to improve the brake discs for bicycles. As a result, an improved product similar to the related function structure was actually created.

  6. Dual Component Removable Partial Denture shows improved ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-02-18

    Feb 18, 2009 ... 2Faculty of Dentistry, the University of Hong Kong, Hong Kong. 3Department of ... an example of poor oral condition caused mainly by periodontitis, and ... working model of the Dual Component Removable Partial Denture.

  7. IPRDS: component histories and nuclear plant aging

    International Nuclear Information System (INIS)

    Borkowski, R.J.; Kahl, W.K.

    1984-01-01

    A comprehensive assessment of nuclear power plant component operating histories, maintenance histories, and design and fabrication details is essential to understanding aging phenomena. As part of the In-Plant Reliability Data System (IPRDS), an attempt is being made to collect and analyze such information from a sampling of US nuclear power plants. Utilizing the IPRDS, one can reconstruct the failure history of the components and gain new insight into the causes and modes of failures resulting from normal or premature aging. This information assembled from the IPRDS can be combined with operating histories and postservice component inspection results for cradle-to-grave assessments of component aging under operating conditions. A comprehensive aging assessment can then be used to provide guidelines for improving the detection, monitoring, and mitigation of aging-related failures

  8. Residual strength evaluation of concrete structural components ...

    Indian Academy of Sciences (India)

    fundamental material parameters that can be determined for use in design or evaluation. ... of plain and reinforced concrete beams using fracture mechanics principles. Design equations ... components accounting for tension softening effect.

  9. Transport, logistics and packaging of ITER components

    International Nuclear Information System (INIS)

    Guerin, Olivier; Couturier, Bruno; Maas, Akko

    2005-01-01

    Cadarache, the European site for ITER, is located at around 50km as the crow flies from the sea. The feasibility of the transport of large and heavy ITER components has thus been thoroughly studied. These studies have covered the following items: - possible itineraries between the most convenient harbour (Fos) and Cadarache; - packaging (in particular for the largest and heaviest components); - means of transport (two types of trailers allowing to avoid lifting and load transfers); - logistics (analysis of transfer kinematics, including temporary storage); - administrative procedures and planning for the road adaptation, taking benefit of the recent successful implementation in the south-west of France of an itinerary for the Airbus A380 components. These studies, performed between 2001 and 2003, led to a viable solution, with a reasonable cost, fully supported by the French authorities. The planning necessary to implement the road modifications is also fully compatible with the expected dates of ITER components delivery

  10. Remembering components of food in Drosophila

    Directory of Open Access Journals (Sweden)

    Gaurav eDas

    2016-02-01

    Full Text Available Remembering features of past feeding experience can refine foraging and food choice. Insects can learn to associate sensory cues with components of food, such as sugars, amino acids, water, salt, alcohol, toxins and pathogens. In the fruit fly Drosophila some food components activate unique subsets of dopaminergic neurons that innervate distinct functional zones on the mushroom bodies. This architecture suggests that the overall dopaminergic neuron population could provide a potential cellular substrate through which the fly might learn to value a variety of food components. In addition, such an arrangement predicts that individual component memories reside in unique locations. Dopaminergic neurons are also critical for food memory consolidation and deprivation-state dependent motivational control of the expression of food-relevant memories. Here we review our current knowledge of how nutrient-specific memories are formed, consolidated and specifically retrieved in insects, with a particular emphasis on Drosophila.

  11. Analysis of failed nuclear plant components

    Science.gov (United States)

    Diercks, D. R.

    1993-12-01

    Argonne National Laboratory has conducted analyses of failed components from nuclear power- gener-ating stations since 1974. The considerations involved in working with and analyzing radioactive compo-nents are reviewed here, and the decontamination of these components is discussed. Analyses of four failed components from nuclear plants are then described to illustrate the kinds of failures seen in serv-ice. The failures discussed are (1) intergranular stress- corrosion cracking of core spray injection piping in a boiling water reactor, (2) failure of canopy seal welds in adapter tube assemblies in the control rod drive head of a pressurized water reactor, (3) thermal fatigue of a recirculation pump shaft in a boiling water reactor, and (4) failure of pump seal wear rings by nickel leaching in a boiling water reactor.

  12. Components of Inventory Change (CINCH) Reports

    Data.gov (United States)

    Department of Housing and Urban Development — The Components of Inventory Change (CINCH) report measures changes in the characteristics of the housing stock of the United States. Using data collected from the...

  13. Technology development for special nuclear components

    International Nuclear Information System (INIS)

    Sanatkumar, A.

    1994-01-01

    One of the attractive features of Candu Pressurised Heavy Water Reactor design which influenced the decision to make it the foundation of our nuclear power programme, is that its main components (calandria, end shields, coolant channel components) are relatively simple - in comparison with reactor pressure vessel and associated components of Boiling Water Reactors or Pressurised Water Reactors - and considered to be within the scope of manufacture of developing countries. Over the last two decades, India has been very successful in technology development in many important and critical areas. We are now about to launch the construction of the first 500 MWe PHWR project at Tarapur. In this context, this paper focuses attention on some of the aspects relating to self-reliance in design, engineering and manufacture of these special components as currently perceived. (author). 3 refs

  14. Integrating Data Transformation in Principal Components Analysis

    KAUST Repository

    Maadooliat, Mehdi; Huang, Jianhua Z.; Hu, Jianhua

    2015-01-01

    Principal component analysis (PCA) is a popular dimension reduction method to reduce the complexity and obtain the informative aspects of high-dimensional datasets. When the data distribution is skewed, data transformation is commonly used prior

  15. Modified cleaning method for biomineralized components

    Science.gov (United States)

    Tsutsui, Hideto; Jordan, Richard W.

    2018-02-01

    The extraction and concentration of biomineralized components from sediment or living materials is time consuming and laborious and often involves steps that remove either the calcareous or siliceous part, in addition to organic matter. However, a relatively quick and easy method using a commercial cleaning fluid for kitchen drains, sometimes combined with a kerosene soaking step, can produce remarkable results. In this study, the method is applied to sediments and living materials bearing calcareous (e.g., coccoliths, foraminiferal tests, holothurian ossicles, ichthyoliths, and fish otoliths) and siliceous (e.g., diatom valves, silicoflagellate skeletons, and sponge spicules) components. The method preserves both components in the same sample, without etching or partial dissolution, but is not applicable to unmineralized components such as dinoflagellate thecae, tintinnid loricae, pollen, or plant fragments.

  16. The multi-component WKI hierarchy

    International Nuclear Information System (INIS)

    Yao Yuqin; Zhang Yufeng

    2005-01-01

    Firstly a new loop algebra G∼ M with 3M dimensions is constructed, which is devoted to establishing a new isospectral problem. Then the multi-component WKI hierarchy of soliton equations is obtained

  17. Solid State Lighting Reliability Components to Systems

    CERN Document Server

    Fan, XJ

    2013-01-01

    Solid State Lighting Reliability: Components to Systems begins with an explanation of the major benefits of solid state lighting (SSL) when compared to conventional lighting systems including but not limited to long useful lifetimes of 50,000 (or more) hours and high efficacy. When designing effective devices that take advantage of SSL capabilities the reliability of internal components (optics, drive electronics, controls, thermal design) take on critical importance. As such a detailed discussion of reliability from performance at the device level to sub components is included as well as the integrated systems of SSL modules, lamps and luminaires including various failure modes, reliability testing and reliability performance. This book also: Covers the essential reliability theories and practices for current and future development of Solid State Lighting components and systems Provides a systematic overview for not only the state-of-the-art, but also future roadmap and perspectives of Solid State Lighting r...

  18. Software Component Certification: 10 Useful Distinctions

    National Research Council Canada - National Science Library

    Wallnau, Kurt C

    2004-01-01

    .... One persistent and largely unaddressed challenge is how the consumers of software components-that is, the developers of mission-critical systems-can obtain a meaningful level of trust in the runtime...

  19. Laser based refurbishment of steel mill components

    CSIR Research Space (South Africa)

    Kazadi, P

    2006-03-01

    Full Text Available Laser refurbishment capabilities were demonstrated and promising results were obtained for repair of distance sleeves, foot rolls, descaler cassette, idler rolls. Based on the cost projections and the results of the in-situ testing, components which...

  20. NEPR Principle Component Analysis - NOAA TIFF Image

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This GeoTiff is a representation of seafloor topography in Northeast Puerto Rico derived from a bathymetry model with a principle component analysis (PCA). The area...

  1. Common cause failures of reactor pressure components

    International Nuclear Information System (INIS)

    Mankamo, T.

    1978-01-01

    The common cause failure is defined as a multiple failure event due to a common cause. The existence of common failure causes may ruin the potential advantages of applying redundancy for reliability improvement. Examples relevant to large mechanical components are presented. Preventive measures against common cause failures, such as physical separation, equipment diversity, quality assurance, and feedback from experience are discussed. Despite the large number of potential interdependencies, the analysis of common cause failures can be done within the framework of conventional reliability analysis, utilizing, for example, the method of deriving minimal cut sets from a system fault tree. Tools for the description and evaluation of dependencies between components are discussed: these include the model of conditional failure causes that are common to many components, and evaluation of the reliability of redundant components subjected to a common load. (author)

  2. Collective fluctuations in networks of noisy components

    International Nuclear Information System (INIS)

    Masuda, Naoki; Kawamura, Yoji; Kori, Hiroshi

    2010-01-01

    Collective dynamics result from interactions among noisy dynamical components. Examples include heartbeats, circadian rhythms and various pattern formations. Because of noise in each component, collective dynamics inevitably involve fluctuations, which may crucially affect the functioning of the system. However, the relation between the fluctuations in isolated individual components and those in collective dynamics is not clear. Here, we study a linear dynamical system of networked components subjected to independent Gaussian noise and analytically show that the connectivity of networks determines the intensity of fluctuations in the collective dynamics. Remarkably, in general directed networks including scale-free networks, the fluctuations decrease more slowly with system size than the standard law stated by the central limit theorem. They even remain finite for a large system size when global directionality of the network exists. Moreover, such non-trivial behavior appears even in undirected networks when nonlinear dynamical systems are considered. We demonstrate it with a coupled oscillator system.

  3. Perspective : component tracking on the Nova system

    International Nuclear Information System (INIS)

    MacDonald, S.

    1999-01-01

    The issue of introducing Component Tracking as a service to natural gas producers, shippers and straddle plant operators was discussed. Approximately 39 companies in the industry were contacted by consultants at Nova Gas Transmission in an effort to assess if introducing this service would add value to individual producers. The numerous implications that may have to be dealt with if Component Tracking is introduced were also described. Component Tracking would provide an equitable approach to the allocation of molecules in the gas stream, and could provide producers with the ability to avoid capital outlay in field plants by alternatively contracting for recovery of the liquids at the straddle plants. Component Tracking is to be voluntary and each shipper would be able to decide whether to utilize the service at each of their receipt points onto the Nova system

  4. Cognitive components of rural tourism destination images

    DEFF Research Database (Denmark)

    Kokkali, Panagiota; Koutsouris, Alex; Chrysochou, Polymeros

    This paper aims at exploring issues related to rural tourism destination image focusing on TDI cognitive components. By means of empirical research addressing tourists visiting the Lake Plastiras area, Central Greece, the cognitive components of the area's TDI were identified along with their eff......This paper aims at exploring issues related to rural tourism destination image focusing on TDI cognitive components. By means of empirical research addressing tourists visiting the Lake Plastiras area, Central Greece, the cognitive components of the area's TDI were identified along......; (3) visitors can be classified in four clusters according the cognitive factors; (4) tourists' clusters differ in terms of age, education and income as well as number of visits and perception of the area's attractiveness. Such findings point towards the need of both a new strategy for the area...

  5. Fatigue evaluation in reactor vessel components

    International Nuclear Information System (INIS)

    Mattar Neto, Miguel; Miranda, Carlos A. de J.

    1994-01-01

    This paper presents a sequence of increasing complexity forms of evaluating fatigue damage of nuclear pressure vessel components caused by cycling loadings. Examples are included in order to illustrate such procedures. (author)

  6. Genetics Home Reference: complement component 2 deficiency

    Science.gov (United States)

    ... Topic: Immune System and Disorders Health Topic: Lupus Genetic and Rare Diseases Information Center (1 link) Complement component 2 deficiency Additional NIH Resources (1 link) National Institute of Allergy and Infectious Diseases: Primary Immune Deficiency Diseases Educational Resources (6 ...

  7. Analysis Method for Integrating Components of Product

    International Nuclear Information System (INIS)

    Choi, Jun Ho; Lee, Kun Sang

    2017-01-01

    This paper presents some of the methods used to incorporate the parts constituting a product. A new relation function concept and its structure are introduced to analyze the relationships of component parts. This relation function has three types of information, which can be used to establish a relation function structure. The relation function structure of the analysis criteria was established to analyze and present the data. The priority components determined by the analysis criteria can be integrated. The analysis criteria were divided based on their number and orientation, as well as their direct or indirect characteristic feature. This paper presents a design algorithm for component integration. This algorithm was applied to actual products, and the components inside the product were integrated. Therefore, the proposed algorithm was used to conduct research to improve the brake discs for bicycles. As a result, an improved product similar to the related function structure was actually created.

  8. Lifetime assessment of service-exposed components

    International Nuclear Information System (INIS)

    Kalwa, G.; Weber, H.

    1988-01-01

    A longtime prognosis on the operation of creep-exposed components requires a lifetime analysis. The basis for such an analysis can be improved by an analysis of microstructure and material properties. Actually the grade of material exhaustion has to be regarded as proper assessment quantity. However, stress and time safety also are valuable assessment quantities which should be taken into consideration, especially when the grade of exhaustion is uncertain because of inaccurate input parameters. A correct assessment of the damage state cannot be made without taking into consideration the failure mechanism which has to be assumed for a specific component. With respect to creep the most critical component of a steamline system is the pipe bend because of the risk of large damage events. For this case component metallography by replicas is suggested as preventive test method. The continuation of service of a creep damage pipe bend cannot be recommended. (orig./MM) [de

  9. Sodium removal from Hallam Reactor components

    International Nuclear Information System (INIS)

    Huntsman, L.K.; Meservey, R.H.

    1979-08-01

    This report discussed the removal of sodium from major components of the Hallam Nuclear Power Facility. This facility contained the experimental ractor used to test the feasibility of sodium coolant. The Idaho Operations Office of the Department of Energy assigned EG and G Idaho, Inc., the task of carrying out this decontamination and decommissioning program at the Idaho National Engineering Laboratory (INEL). Since their shipment to the INEL from Lincoln, Nebraska in 1968, the Hallam Reactor components had been stored in inert nitrogen to prevent the sodium in the components from reacting with moisture in the air. The procedure used to react the sodium in the components and to decontaminate them is discussed. Problems and unusual occurrences in the decontamination and decommissioning process are also reported

  10. Analysis of failed nuclear plant components

    International Nuclear Information System (INIS)

    Diercks, D.R.

    1993-01-01

    Argonne National Laboratory has conducted analyses of failed components from nuclear power-generating stations since 1974. The considerations involved in working with an analyzing radioactive components are reviewed here, and the decontamination of these components is discussed. Analyses of four failed components from nuclear plants are then described to illustrate the kinds of failures seen in service. The failures discussed are (1) intergranular stress-corrosion cracking of core spray injection piping in a boiling water reactor, (2) failure of canopy seal welds in adapter tube assemblies in the control rod drive head of a pressurized water reactor, (3) thermal fatigue of a recirculation pump shaft in a boiling water reactor, and (4) failure of pump seal wear rings by nickel leaching in a boiling water reactor

  11. Analysis of failed nuclear plant components

    International Nuclear Information System (INIS)

    Diercks, D.R.

    1992-07-01

    Argonne National Laboratory has conducted analyses of failed components from nuclear power generating stations since 1974. The considerations involved in working with and analyzing radioactive components are reviewed here, and the decontamination of these components is discussed. Analyses of four failed components from nuclear plants are then described to illustrate the kinds of failures seen in service. The failures discussed are (a) intergranular stress corrosion cracking of core spray injection piping in a boiling water reactor, (b) failure of canopy seal welds in adapter tube assemblies in the control rod drive head of a pressure water reactor, (c) thermal fatigue of a recirculation pump shaft in a boiling water reactor, and (d) failure of pump seal wear rings by nickel leaching in a boiling water reactor

  12. Modeling the degradation of nuclear components

    International Nuclear Information System (INIS)

    Stock, D.; Samanta, P.; Vesely, W.

    1993-01-01

    This paper describes component level reliability models that use information on degradation to predict component reliability, and which have been used to evaluate different maintenance and testing policies. The models are based on continuous time Markov processes, and are a generalization of reliability models currently used in Probabilistic Risk Assessment. An explanation of the models, the model parameters, and an example of how these models can be used to evaluate maintenance policies are discussed

  13. Leadership Stability in Army Reserve Component Units

    Science.gov (United States)

    2013-01-01

    OMB control number. 1. REPORT DATE 2013 2. REPORT TYPE 3. DATES COVERED 00-00-2013 to 00-00-2013 4. TITLE AND SUBTITLE Leadership Stability in...standards for research quality and objectivity. Leadership Stability in Army Reserve Component Units Thomas F. Lippiatt, J. Michael Polich NATIONAL SECURITY...RESEARCH DIVISION Leadership Stability in Army Reserve Component Units Thomas F. Lippiatt, J. Michael Polich Prepared for the Office of the

  14. Simulation of electromagnetic aggression on components

    International Nuclear Information System (INIS)

    Adoun, G.; Coumar, O.

    1997-01-01

    Numerical simulation techniques can be used for studying the behaviour of electronic components exposed to electromagnetic aggression. This article discusses CW analysis on a CMOS-technology logic NAND gate under electromagnetic aggression of different amplitudes (2.5 V 5 V), frequencies (100 MHz and 1 GHz) and phase. Numerical simulations were conducted using three codes: Spice code was used for solving electronic circuits, and the Atlas and Dessis codes were used for examining internal component behaviour. (authors)

  15. A radiographic analysis of implant component misfit.

    LENUS (Irish Health Repository)

    Sharkey, Seamus

    2011-07-01

    Radiographs are commonly used to assess the fit of implant components, but there is no clear agreement on the amount of misfit that can be detected by this method. This study investigated the effect of gap size and the relative angle at which a radiograph was taken on the detection of component misfit. Different types of implant connections (internal or external) and radiographic modalities (film or digital) were assessed.

  16. Accurate modeling of UV written waveguide components

    DEFF Research Database (Denmark)

    Svalgaard, Mikael

    BPM simulation results of UV written waveguide components that are indistinguishable from measurements can be achieved on the basis of trajectory scan data and an equivalent step index profile that is very easy to measure.......BPM simulation results of UV written waveguide components that are indistinguishable from measurements can be achieved on the basis of trajectory scan data and an equivalent step index profile that is very easy to measure....

  17. Accurate modelling of UV written waveguide components

    DEFF Research Database (Denmark)

    Svalgaard, Mikael

    BPM simulation results of UV written waveguide components that are indistinguishable from measurements can be achieved on the basis of trajectory scan data and an equivalent step index profile that is very easy to measure.......BPM simulation results of UV written waveguide components that are indistinguishable from measurements can be achieved on the basis of trajectory scan data and an equivalent step index profile that is very easy to measure....

  18. Inspection and repair of nuclear components

    International Nuclear Information System (INIS)

    Lahner, K.; Poetz, F.

    1993-01-01

    Despite careful design, manufacturing and operation, some of the important safety-relevant components show deterioration with time. Because of activation and contamination of these components, their inspection and repair has to be performed with manipulators. Some sophisticated manipulators are described, built by ABB Reaktor and used for inspection, maintenance and repair of PWR steam generators, fuel alignment pins, core baffle former bolts and reactor pressure vessel head penetrations. (Z.S.) 7 figs

  19. Structured Performance Analysis for Component Based Systems

    OpenAIRE

    Salmi , N.; Moreaux , Patrice; Ioualalen , M.

    2012-01-01

    International audience; The Component Based System (CBS) paradigm is now largely used to design software systems. In addition, performance and behavioural analysis remains a required step for the design and the construction of efficient systems. This is especially the case of CBS, which involve interconnected components running concurrent processes. % This paper proposes a compositional method for modeling and structured performance analysis of CBS. Modeling is based on Stochastic Well-formed...

  20. Component aging evaluation with expert systems

    International Nuclear Information System (INIS)

    Wiesemann, J.S.; Maguire, H.T. Jr.

    1988-01-01

    The age degradation of components involves a complex relationship between a variety of variables. These relationships are typically modeled using probabilistic and deterministic analyses. These methods depend upon a formal understanding of the underlying degradation mechanisms and a database of experience which allows statistical analyses to extract numerical trends. At present, not all age degradation mechanisms are adequately modeled and available data for age degradation is in most cases insufficient. In addition, these methods tend to focus upon answers to isolated questions (e.g., What is the component failure rate?) rather than the more pertinent questions concerning operations and maintenance (e.g., should the component be replaced at the next outage). Fortunately, knowledge in the form of personal experience does exist which allows plant personnel to make decisions concerning operations and maintenance. This knowledge can be modeled using expert systems. This paper discusses CAGES (Component Aging Expert System). It combines expert rules (heuristics), probabilistic models, and deterministic models to make evaluations of component aging; predict the implications for component life extension, operational readiness, maintenance effectiveness, and safety, and make recommendations for maintenance and operation

  1. Crack growth determination on laboratory components

    International Nuclear Information System (INIS)

    Hurst, R.C.

    1993-01-01

    In order to aid design and support remanent life assessment of plant components operating at elevated temperatures, the reliability of the analytical methods, which translate materials data procured from the laboratory to the behaviour of actual components, requires validation. Such a validation can of course be interpreted from operating plant, however the potential risks involved encourage the development of out of plant techniques for the validation of representative components. For meaningful validation, these techniques need careful control and high accuracy which can best be achieved in a laboratory environment. As the laboratory component test should be designed to simulate actual plant conditions as closely as possible, the direct extension of the results to the plant component case requires scaling up. Consequently the successful development of such a test may even lead to the advantageous situation where it could form an alternative to the conventional route where, for example, it may not be possible to obtain the plant component's metallurgical structure in a conventional specimen or, alternatively, when too many assumptions are required in the analysis when translating to different geometries and stress systems. Under these conditions, in spite of the more sophisticated test requirements, it may prove more reasonable to opt for the more representative laboratory component data for use in design or lifetime prediction. The present work describes the application of the component validation test philosophy to the problem of crack growth under two rather different loading conditions. In both cases, crack growth is measured using the direct current potential drop (PD) technique on tubular metallic components containing artificial defects, however the plant conditions to be simulated lead to either creep or thermal fatigue. The creep studies on Alloy 800H support heat exchanger design for nuclear plant, solar towers and chemical plant, whereas the work on the

  2. Component Repair Times Obtained from MSPI Data

    International Nuclear Information System (INIS)

    Eide, Steven A.; Cadwallader, Lee

    2015-01-01

    Information concerning times to repair or restore equipment to service given a failure is valuable to probabilistic risk assessments (PRAs). Examples of such uses in modern PRAs include estimation of the probability of failing to restore a failed component within a specified time period (typically tied to recovering a mitigating system before core damage occurs at nuclear power plants) and the determination of mission times for support system initiating event (SSIE) fault tree models. Information on equipment repair or restoration times applicable to PRA modeling is limited and dated for U.S. commercial nuclear power plants. However, the Mitigating Systems Performance Index (MSPI) program covering all U.S. commercial nuclear power plants provides up-to-date information on restoration times for a limited set of component types. This paper describes the MSPI program data available and analyzes the data to obtain median and mean component restoration times as well as non-restoration cumulative probability curves. The MSPI program provides guidance for monitoring both planned and unplanned outages of trains of selected mitigating systems deemed important to safety. For systems included within the MSPI program, plants monitor both train UA and component unreliability (UR) against baseline values. If the combined system UA and UR increases sufficiently above established baseline results (converted to an estimated change in core damage frequency or CDF), a ''white'' (or worse) indicator is generated for that system. That in turn results in increased oversight by the US Nuclear Regulatory Commission (NRC) and can impact a plant's insurance rating. Therefore, there is pressure to return MSPI program components to service as soon as possible after a failure occurs. Three sets of unplanned outages might be used to determine the component repair durations desired in this article: all unplanned outages for the train type that includes the component of

  3. Performance Engineering Technology for Scientific Component Software

    Energy Technology Data Exchange (ETDEWEB)

    Malony, Allen D.

    2007-05-08

    Large-scale, complex scientific applications are beginning to benefit from the use of component software design methodology and technology for software development. Integral to the success of component-based applications is the ability to achieve high-performing code solutions through the use of performance engineering tools for both intra-component and inter-component analysis and optimization. Our work on this project aimed to develop performance engineering technology for scientific component software in association with the DOE CCTTSS SciDAC project (active during the contract period) and the broader Common Component Architecture (CCA) community. Our specific implementation objectives were to extend the TAU performance system and Program Database Toolkit (PDT) to support performance instrumentation, measurement, and analysis of CCA components and frameworks, and to develop performance measurement and monitoring infrastructure that could be integrated in CCA applications. These objectives have been met in the completion of all project milestones and in the transfer of the technology into the continuing CCA activities as part of the DOE TASCS SciDAC2 effort. In addition to these achievements, over the past three years, we have been an active member of the CCA Forum, attending all meetings and serving in several working groups, such as the CCA Toolkit working group, the CQoS working group, and the Tutorial working group. We have contributed significantly to CCA tutorials since SC'04, hosted two CCA meetings, participated in the annual ACTS workshops, and were co-authors on the recent CCA journal paper [24]. There are four main areas where our project has delivered results: component performance instrumentation and measurement, component performance modeling and optimization, performance database and data mining, and online performance monitoring. This final report outlines the achievements in these areas for the entire project period. The submitted progress

  4. Component Repair Times Obtained from MSPI Data

    Energy Technology Data Exchange (ETDEWEB)

    Eide, Steven A. [Curtiss-Wright/Scietech, Ketchum, ID (United States); Cadwallader, Lee [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-05-01

    Information concerning times to repair or restore equipment to service given a failure is valuable to probabilistic risk assessments (PRAs). Examples of such uses in modern PRAs include estimation of the probability of failing to restore a failed component within a specified time period (typically tied to recovering a mitigating system before core damage occurs at nuclear power plants) and the determination of mission times for support system initiating event (SSIE) fault tree models. Information on equipment repair or restoration times applicable to PRA modeling is limited and dated for U.S. commercial nuclear power plants. However, the Mitigating Systems Performance Index (MSPI) program covering all U.S. commercial nuclear power plants provides up-to-date information on restoration times for a limited set of component types. This paper describes the MSPI program data available and analyzes the data to obtain median and mean component restoration times as well as non-restoration cumulative probability curves. The MSPI program provides guidance for monitoring both planned and unplanned outages of trains of selected mitigating systems deemed important to safety. For systems included within the MSPI program, plants monitor both train UA and component unreliability (UR) against baseline values. If the combined system UA and UR increases sufficiently above established baseline results (converted to an estimated change in core damage frequency or CDF), a “white” (or worse) indicator is generated for that system. That in turn results in increased oversight by the US Nuclear Regulatory Commission (NRC) and can impact a plant’s insurance rating. Therefore, there is pressure to return MSPI program components to service as soon as possible after a failure occurs. Three sets of unplanned outages might be used to determine the component repair durations desired in this article: all unplanned outages for the train type that includes the component of interest, only

  5. Femoral component rotation in patellofemoral joint replacement.

    Science.gov (United States)

    van Jonbergen, Hans-Peter W; Westerbeek, Robin E

    2018-06-01

    Clinical outcomes in patellofemoral joint replacement may be related to femoral component rotation. Assessment of rotational alignment is however difficult as patients with isolated patellofemoral osteoarthritis often have trochlear dysplasia. The use of the medial malleolus as a landmark to guide rotation has been suggested. The purpose of our study was to evaluate this technique with regard to femoral component rotation, and to correlate rotation with clinical outcomes at one-year follow-up. Forty-one knees in 39 patients had patellofemoral joint replacement using the Zimmer Gender-Solutions patellofemoral prosthesis. Intraoperatively, we determined femoral component rotational alignment using an extramedullary rod aimed at the inferior tip of the medial malleolus. Postoperatively, we measured the angle between the femoral component and the anatomical transepicondylar axis using CT. The amount of rotation was correlated with clinical outcomes at one-year follow-up. Forty knees in 38 patients were available for one-year follow-up. Mean femoral component rotation relative to the anatomical transepicondylar axis was 1.4° external rotation (range, -3.8 to 5.7°). We found no statistically significant correlation between femoral component rotation and change from baseline KOOS subscales at one-year follow-up. Our findings show that when using the medial malleolus as a landmark to guide rotation, the femoral component of the patellofemoral prosthesis was oriented in external rotation relative to the anatomical transepicondylar axis in 80% of knees. Our study did not show a relation between the amount of external rotation and clinical outcomes. Level III. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. 17.9.3 Radical cations of diazo compounds

    Science.gov (United States)

    Davies, A. G.

    This document is part of Subvolume E2 `Phosphorus-Centered Radicals, Radicals Centered on Other Heteroatoms, Organic Radical Ions' of Volume 26 `Magnetic Properties of Free Radicals' of Landolt-Börnstein Group II `Molecules and Radicals'.

  7. pH controlled diazo coupling of aldolase

    International Nuclear Information System (INIS)

    Montagnoli, G.; Balestreri, E.; Nannicini, L.; Bellucci, A.; Bracaloni, M.

    1978-01-01

    pH conditions have been found which achieve selective reaction of diazotized p-amino benzoate with cysteine residues of rabbit muscle aldolase. The difference in reactivity of the two sulphydryl groups involved, (Cys-237 and Cys-287) permits one to form either four or eight diazothioethers on the tetrameric enzyme and obtain a homogeneous protein. In both cases the enzyme became slightly more active in the fructose-1, 6-bisphosphate cleavage, the K sub(M) value being retained. The results have been discussed with regard to chemically modifying an enzyme to change its physical, chemical and immunological properties, whilst leaving the catalytical activity unmodified. (author)

  8. Fluorogenic Strain-Promoted Alkyne-Diazo Cycloadditions

    NARCIS (Netherlands)

    Friscourt, Frédéric; Fahrni, Christoph J.; Boons, Geert Jan

    2015-01-01

    Fluorogenic reactions, in which non- or weakly fluorescent reagents produce highly fluorescent products, are attractive for detecting a broad range of compounds in the fields of bioconjugation and material sciences. Herein, we report that a dibenzocyclooctyne derivative modified with a

  9. Investigation of nonionic diazo dye-doped polymer dispersed liquid ...

    Indian Academy of Sciences (India)

    ferent concentrations in LC at voltage off was measured. To measure .... plays smaller and more uniform distribution of LC droplets at lower .... Further a drop from these solutions is .... ever, in this system for bigger the droplet size, the larger the.

  10. Component-Based Cartoon Face Generation

    Directory of Open Access Journals (Sweden)

    Saman Sepehri Nejad

    2016-11-01

    Full Text Available In this paper, we present a cartoon face generation method that stands on a component-based facial feature extraction approach. Given a frontal face image as an input, our proposed system has the following stages. First, face features are extracted using an extended Active Shape Model. Outlines of the components are locally modified using edge detection, template matching and Hermit interpolation. This modification enhances the diversity of output and accuracy of the component matching required for cartoon generation. Second, to bring cartoon-specific features such as shadows, highlights and, especially, stylish drawing, an array of various face photographs and corresponding hand-drawn cartoon faces are collected. These cartoon templates are automatically decomposed into cartoon components using our proposed method for parameterizing cartoon samples, which is fast and simple. Then, using shape matching methods, the appropriate cartoon component is selected and deformed to fit the input face. Finally, a cartoon face is rendered in a vector format using the rendering rules of the selected template. Experimental results demonstrate effectiveness of our approach in generating life-like cartoon faces.

  11. Robust Spacecraft Component Detection in Point Clouds

    Directory of Open Access Journals (Sweden)

    Quanmao Wei

    2018-03-01

    Full Text Available Automatic component detection of spacecraft can assist in on-orbit operation and space situational awareness. Spacecraft are generally composed of solar panels and cuboidal or cylindrical modules. These components can be simply represented by geometric primitives like plane, cuboid and cylinder. Based on this prior, we propose a robust automatic detection scheme to automatically detect such basic components of spacecraft in three-dimensional (3D point clouds. In the proposed scheme, cylinders are first detected in the iteration of the energy-based geometric model fitting and cylinder parameter estimation. Then, planes are detected by Hough transform and further described as bounded patches with their minimum bounding rectangles. Finally, the cuboids are detected with pair-wise geometry relations from the detected patches. After successive detection of cylinders, planar patches and cuboids, a mid-level geometry representation of the spacecraft can be delivered. We tested the proposed component detection scheme on spacecraft 3D point clouds synthesized by computer-aided design (CAD models and those recovered by image-based reconstruction, respectively. Experimental results illustrate that the proposed scheme can detect the basic geometric components effectively and has fine robustness against noise and point distribution density.

  12. EU R and D on divertor components

    International Nuclear Information System (INIS)

    Merola, M.; Daenner, W.; Pick, M.

    2005-01-01

    Since the last SOFT conference held in Helsinki in 2002, substantial progress has been made in the EU R and D on the divertor components. A number of activities have been completed and new ones have been launched. The present paper gives an update of the works carried out by the EU Participating Team in support of the development of the divertor, which is one of the most challenging components of the next-step ITER machine. The following topics are covered: (1) the further development and consolidation of suitable technologies for the production of high heat-flux components, which culminated with the successful manufacturing and testing of a full-scale vertical target prototype; (2) the completion of the post-irradiation testing of divertor mock-ups and samples; (3) the preparation for the hydraulic and assembly tests of a complete set of full-scale divertor components; (4) the on-going R and D on the definition of workable acceptance criteria for the procurement of ITER high heat-flux components; (5) the activities in support of the divertor design

  13. Translation of Onomatopoetic Component in Onomastics

    Directory of Open Access Journals (Sweden)

    Анна Владимировна Соколова

    2015-12-01

    Full Text Available This article covers the topic of the description of translation strategies of onomatopoetic component of proper names. The term of onomatopoetic proper names is introduced for the first time. The article is the fist work that gives a view of onomatopoetic component in proper names on the material of English proper names, product names, electronic resources, theatre plays and cartoon titles. Onomatopoeia in onomastics is seen form the viewpoint of sociolinguistics. Being an aspect of literary onomastics, onomatopoetic proper names are considered to be a functional and semantic word mark (meaning-creating and text-forming that serves as an individualizing and characteristic device. However examples of onomatopoeia in onomastics are seen not only in imaginative literature but also in advertisements and commercials. Onomatopoetic component is a unique device that allows to verbalize lingvocultural aspects of proper names. These names are pleasant to hear and easy to remember. They help to make up brand names. Translation strategies include two techniques: translator often resorts to borrowings, in other words transliterateration or transcription of the original onomatopoeia, or makes situational equivalents like occasionalisms or oral speech equivalents to render the expressive, stylistic and evaluative components of meaning of such proper names. This article will give an example of both these techniques and deduce the most affective strategies that can be applied to translation of onomatopoetic component of proper names.

  14. Flight service evaluation of composite helicopter components

    Science.gov (United States)

    Mardoian, George H.; Ezzo, Maureen B.

    1994-01-01

    This paper presents the results of a NASA funded contract and Sikorsky research and development programs to evaluate structural composite components in flight service on Sikorsky Model S-76 helicopters. Selected components were removed and tested at prescribed intervals over a nine year time frame. Four horizontal stabilizers and thirteen tail rotor spars were returned from commercial service in West Palm Beach, Florida and in the Gulf Coast region of Louisiana to determine the long term effects of operations in hot and humid climates on component performance. Concurrent with the flight component evaluation, panels of materials used in their fabrication were exposed to the environment in ground racks. Selected panels were tested annually to determine the effects of exposure on physical and mechanical properties. The results of 55,741 component flight hours and 911 months of field exposure are reported and compared with initial Federal Aviation Administration (FAA) certification data. The findings of this program have provided increased confidence in the long term durability of advanced composite materials used in helicopter structural applications.

  15. Selection of components based on their importance

    International Nuclear Information System (INIS)

    Stvan, F.

    2004-12-01

    A proposal is presented for sorting components of the Dukovany nuclear power plant with respect to their importance. The classification scheme includes property priority, property criticality and property structure. Each area has its criteria with weight coefficients to calculate the importance of each component by the Risk Priority Number method. The aim of the process is to generate a list of components in order of operating and safety importance, which will help spend funds to ensure operation and safety in an optimal manner. This proposal is linked to a proposal for a simple database which should serve to enter information and perform assessments. The present stage focused on a safety assessment of components categorized in safety classes BT1, BT2 and BT3 pursuant to Decree No. 76. Assessment was performed based ona PSE study for Level 1. The database includes inputs for entering financial data, which are represented by a potential damage resulting from the given failure and by the loss of MWh in financial terms. In a next input, the failure incidence intensity and time of correction can be entered. Information regarding the property structure, represented by the degree of backup and reparability of the component, is the last input available

  16. Robust Spacecraft Component Detection in Point Clouds.

    Science.gov (United States)

    Wei, Quanmao; Jiang, Zhiguo; Zhang, Haopeng

    2018-03-21

    Automatic component detection of spacecraft can assist in on-orbit operation and space situational awareness. Spacecraft are generally composed of solar panels and cuboidal or cylindrical modules. These components can be simply represented by geometric primitives like plane, cuboid and cylinder. Based on this prior, we propose a robust automatic detection scheme to automatically detect such basic components of spacecraft in three-dimensional (3D) point clouds. In the proposed scheme, cylinders are first detected in the iteration of the energy-based geometric model fitting and cylinder parameter estimation. Then, planes are detected by Hough transform and further described as bounded patches with their minimum bounding rectangles. Finally, the cuboids are detected with pair-wise geometry relations from the detected patches. After successive detection of cylinders, planar patches and cuboids, a mid-level geometry representation of the spacecraft can be delivered. We tested the proposed component detection scheme on spacecraft 3D point clouds synthesized by computer-aided design (CAD) models and those recovered by image-based reconstruction, respectively. Experimental results illustrate that the proposed scheme can detect the basic geometric components effectively and has fine robustness against noise and point distribution density.

  17. Untangling Galaxy Components - The Angular Momentum Parameter

    Science.gov (United States)

    Tabor, Martha; Merrifield, Michael; Aragon-Salamanca, Alfonso

    2017-06-01

    We have developed a new technique to decompose Integral Field spectral data cubes into separate bulge and disk components, allowing us to study the kinematic and stellar population properties of the individual components and how they vary with position. We present here the application of this method to a sample of fast rotator early type galaxies from the MaNGA integral field survey, and demonstrate how it can be used to explore key properties of the individual components. By extracting ages, metallicities and the angular momentum parameter lambda of the bulges and disks, we show how this method can give us new insights into the underlying structure of the galaxies and discuss what this can tell us about their evolution history.

  18. Modified planar functions and their components

    DEFF Research Database (Denmark)

    Anbar Meidl, Nurdagül; Meidl, Wilfried Meidl

    2017-01-01

    functions in odd characteristic as a vectorial bent function. We finally point out that though these components behave somewhat different than the multivariate bent4 functions, they are bent or semibent functions shifted by a certain quadratic term, a property which they share with their multivariate......Zhou ([20]) introduced modified planar functions in order to describe (2n; 2n; 2n; 1) relative difference sets R as a graph of a function on the finite field F2n, and pointed out that projections of R are difference sets that can be described by negabent or bent4 functions, which are Boolean...... functions given in multivariate form. One of the objectives of this paper is to contribute to the understanding of these component functions of modified planar functions. Moreover, we obtain a description of modified planar functions by their components which is similar to that of the classical planar...

  19. Principal components analysis in clinical studies.

    Science.gov (United States)

    Zhang, Zhongheng; Castelló, Adela

    2017-09-01

    In multivariate analysis, independent variables are usually correlated to each other which can introduce multicollinearity in the regression models. One approach to solve this problem is to apply principal components analysis (PCA) over these variables. This method uses orthogonal transformation to represent sets of potentially correlated variables with principal components (PC) that are linearly uncorrelated. PCs are ordered so that the first PC has the largest possible variance and only some components are selected to represent the correlated variables. As a result, the dimension of the variable space is reduced. This tutorial illustrates how to perform PCA in R environment, the example is a simulated dataset in which two PCs are responsible for the majority of the variance in the data. Furthermore, the visualization of PCA is highlighted.

  20. The Unknown Component Problem Theory and Applications

    CERN Document Server

    Villa, Tiziano; Brayton, Robert K; Mishchenko, Alan; Petrenko, Alexandre; Sangiovanni-Vincentelli, Alberto

    2012-01-01

    The Problem of the Unknown Component: Theory and Applications addresses the issue of designing a component that, combined with a known part of a system, conforms to an overall specification. The authors tackle this problem by solving abstract equations over a language. The most general solutions are studied when both synchronous and parallel composition operators are used. The abstract equations are specialized to languages associated with important classes of automata used for modeling systems. The book is a blend of theory and practice, which includes a description of a software package with applications to sequential synthesis of finite state machines. Specific topologies interconnecting the components, exact and heuristic techniques, and optimization scenarios are studied. Finally the scope is enlarged to domains like testing, supervisory control, game theory and synthesis for special omega languages. The authors present original results of the authors along with an overview of existing ones.