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Sample records for spiro-crypta phosphazene derivatives

  1. The thermal degradation pathway studies of a phosphazene derivative on cotton fabric

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphazene derivatives have been recognized as promising flame retardants for numerous polymeric systems. However, limited studies are available for phosphazene derivatives on cotton fabric. In this study, a phosphazene derivative 1,1,3,3-dihydroxybiphenyl-5,5-diaminoethanephosphazene (dBEP) was ...

  2. Application of a phosphazene derivative as a flame retardant for cotton fabric using conventional method and supercritical CO2

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Conventional pad-dry-cure (non-scCO2) and supercritical carbon dioxide (scCO2) application methods were investigated to study the effectiveness of a phosphazene derivative as a flame retardant on cotton fabric. 1,1',4,5-tetrahydrotrispiro[1,3,2-diazaphosphole-2,2'-[1,3,5,2,4,6]triazatriphosphinine-4...

  3. Phosphazenes (2010)

    SciTech Connect

    Frederick F. Stewart

    2010-12-01

    A review of the literature published in 2009 shows an increase in the number of publications addressing phosphazene chemistry over 2008, which suggests a continued strong interest in these intriguing materials. Prominently is the emphasis in the bioactive and biocompatible nature of these materials; although many other applications also exist. Phosphazenes are formed from a phosphorus and nitrogen backbone with pendant group attachments at phosphorus. Typically, they are drawn with alternating single and double bonds between the alternating phosphorus and nitrogen atoms. However, unlike the familiar poly(acetylenes) or poly(thiophenes), the phosphazene backbone is not electrically conductive as there are orbital nodes at phosphorus. Thus, electron delocalization occurs between phosphorus atoms, but not through them. The result of this bonding is a highly flexible backbone that can be controlled through adoit pendant group attachment revealing numerous materials and structures. In this review, novel aspects of the chemistry, structure, and applications of phosphazenes will be discussed.

  4. Phosphazenes 2014

    SciTech Connect

    Stewart, Frederick F.

    2015-04-01

    Phosphazene chemistry continues to expand in its breadth and application. This article discusses new research published in 2013 covering mono- and dimeric structures, cyclotriphosphazenes, linear polymers, and the use of phosphazenic structures as ligands on metal centres. Papers report new reactions and structures as well as materials designed for specific applications, such as biomedical, energy storage, flame retardant, and optical, among others. The critical similarity is the phosphazene P-N structure that gives this area of study wide variation. Mirroring the diversity in chemistry are the tools used to probe structure and behaviour. These techniques include Nuclear Magnetic Resonance (NMR) spectrometry, various optical methods, electrochemistry, membrane transport experiments, etc. Furthermore, computational methods, such as Density Functional Theory (DFT), have been used to provide additional insight. This article is organized by structure, beginning with monomeric, dimeric, and non-cyclic phosphazenes first, followed by the cyclic and linear morphologies, with reported potential applications.

  5. Phosphazene additives

    SciTech Connect

    Harrup, Mason K; Rollins, Harry W

    2013-11-26

    An additive comprising a phosphazene compound that has at least two reactive functional groups and at least one capping functional group bonded to phosphorus atoms of the phosphazene compound. One of the at least two reactive functional groups is configured to react with cellulose and the other of the at least two reactive functional groups is configured to react with a resin, such as an amine resin of a polycarboxylic acid resin. The at least one capping functional group is selected from the group consisting of a short chain ether group, an alkoxy group, or an aryloxy group. Also disclosed are an additive-resin admixture, a method of treating a wood product, and a wood product.

  6. Phosphazene diamines

    NASA Technical Reports Server (NTRS)

    Paciorek, K. L.; Harris, D. H.; Ito, T. I.; Kratzer, R. H.

    1980-01-01

    The synthesis of a specific phosphazene diamine was optimized, other phosphorus-containing diamines were prepared, and their effect upon certain characteristics of epoxy resins, prepared via reaction with MY 720, in particular, char yield at elevated temperatures was evaluated. The synthesis of the phosphazene diamine resulting from the interaction of methylenedianline with 4,4'-bis(diphenylphosphino)biphenyl was simplified into a one step process giving 77 percent yield of the pure product. Using this procedure, a related diamine containing bis(diphenylphosphino)methane was obtained in a 70 percent yield. Preparation of another class of phosphorus containing amines based upon p-aminophenyldiphenyl-phosphine was unsuccessful; the inability to produce p-aminophenylithlum was responsible for this failure. Seven epoxy resins employing Araldite MY 720, diaminodiphenylsulfone, and two of the phosphorus containing diamines were prepared, characterized, and their char yield capacity at elevated temperatures assessed. Based on these investigations, the resins containing phosphorus appear to exhibit significantly better char formation characteristics than materials hardened using conventional amines, without impairing the other properties measured.

  7. Phosphazenes (2011)

    SciTech Connect

    Stewart, Frederick F.

    2012-01-01

    Organophosphorus Chemistry provides a comprehensive and critical review of the recent literature. Coverage includes phosphines and their chalcogenides, phosphonium salts, low coordination number phosphorus compounds, penta- and hexa- coordinated compounds, quiquevalent phosphorus acids, nucleotides and nucleic aicds, ylides and related compounds, phosphazenes and the application of physical methods in the study of organophosphorus compounds. This is the 40th in a series of volumes which first appeared in 1970 under the editorship of Stuart Trippett and which covered the literature of organophosphorus chemistry published in the period from January 1968 to June 1969, citing some 1370 publications. The present volume covers the literature from January 2009 to January 2010, citing more than 2200 publications, continuing our efforts to provide an up to date survey of progress in an area of chemistry that has expanded significantly over the past 40 years.

  8. Phosphazenes [book chapter, 2013

    SciTech Connect

    Stewart, Frederick F.

    2013-04-29

    The unique chemistry of phosphazenes continues to be developed. A phosphazene, which is defined as a P(V) and N structure with these atoms attached to each other by double bonds, exhibits a unique two-step general synthesis in which the P=N skeleton is initially formed, followed by nucleophilic substitution to provide final form. In general, a pure inorganic phosphazene is assembled, typically with halide substitution at P. The lability of the P-X bond allows for substitution with a nearly unlimited variety of nucleophiles. Final substitution can yield stable structures amenable to both characterization and function. This article discusses some of the more recent developments in phosphazene chemistry and seeks to provide the reader a picture of the current state of the art.

  9. Novel fire-resistant polyphosphazenes and phosphazene-containing polymers

    NASA Astrophysics Data System (ADS)

    Taylor, Jonathan Paul

    A functionalized polyphosphazene, poly[bis(carboxylatophenoxy)phosphazene], was blended with a structural polyurethane via reactive mixing of the polymer with diisocyanate and diol prepolymers. The thermal stabilities of the resultant foams were analyzed by thermogravimetric analysis (TGA). Both qualitative and quantitative flame tests indicated an increase in flame resistance at loadings of 20 wt% and above. Methods for the incorporation of phosphate and phosphonate units into the side groups of phosphazenes are described and evaluated. Halogenated organophosphates were used as the phosphorylating agents and were allowed to react with hydroxyl- or lithio-functionalized phosphazenes. Well defined phosphorylated cyclic trimers were synthesized from the hydroxyl-functionalized precursors, and these were examined as flame retardant additives to polystyrene. The thermal stabilities of the high polymers made by this route were analyzed by TGA. Ring-opening metathesis polymerization (ROMP) of phosphazene-functionalized norbornenes was demonstrated with the use of the Grubbs catalyst. This allowed the incorporation of alkoxy-, fluoroalkoxy-, and aryloxy-derived cyclic phosphazenes as side groups linked to the organic polymer backbone. The polymers were obtained in moderate yields with the properties being dependent on the side groups present and on the molecular weight. In addition, cyclooctenes and norbornenes with cyclic phosphazene side units bearing trifluoroethoxy or phenoxy groups were polymerized via ROMP using a ruthenium based initiator. The same monomers were also copolymerized with 90--99 mole percent of cyclooctene, norbornene, dicyclopentadiene, or exo,exo-5,6-bis(methoxycarbonyl)-7-oxabicyclo[2.2.1]hept-2-ene. The presence of as little as 2 mol% of the cyclic phosphazene in the copolymers dramatically reduced the combustibility. Poly(diphenyl-p-styrylphosphine) and copolymers of diphenyl- p-styrylphosphine with either styrene or methyl methacrylate were

  10. Phosphazene membranes for gas separations

    DOEpatents

    Stewart, Frederick F.; Harrup, Mason K.; Orme, Christopher J.; Luther, Thomas A.

    2006-07-11

    A polyphosphazene having a glass transition temperature ("T.sub.g") of approximately -20.degree. C. or less. The polyphosphazene has at least one pendant group attached to a backbone of the polyphosphazene, wherein the pendant group has no halogen atoms. In addition, no aromatic groups are attached to an oxygen atom that is bound to a phosphorus atom of the backbone. The polyphosphazene may have a T.sub.g ranging from approximately -100.degree. C. to approximately -20.degree. C. The polyphosphazene may be selected from the group consisting of poly[bis-3-phenyl-1-propoxy)phosphazene], poly[bis-(2-phenyl-1-ethoxy)phosphazene], poly[bis-(dodecanoxypolyethoxy)-phosphazene], and poly[bis-(2-(2-(2-.omega.-undecylenyloxyethoxy)ethoxy)ethoxy)phosphazene]- . The polyphosphazene may be used in a separation membrane to selectively separate individual gases from a gas mixture, such as to separate polar gases from nonpolar gases in the gas mixture.

  11. Phosphazene polymer containing composites and method for making phosphazene polymer containing composites

    DOEpatents

    Allen, Charles A.; Grey, Alan E.; McCaffrey, Robert R.; Simpson, Brenda M.; Stone, Mark L.

    1994-01-01

    A composite is produced by first coating a reinforcing material with an inorganic phosphazene compound and then polymerizing the phosphazene compound so as to confer superior thermal, physical and chemical resistance qualities to the composite.

  12. Phosphazene polymer containing composites and method for making phosphazene polymer containing composites

    DOEpatents

    Allen, Charles A.; Grey, Alan E.; McCaffrey, Robert R.; Simpson, Brenda M.; Stone, Mark L.

    1994-05-03

    A composite is produced by first coating a reinforcing material with an inorganic phosphazene compound and then polymerizing the phosphazene compound so as to confer superior thermal, physical and chemical resistance qualities to the composite.

  13. Carboranylmethylene-substituted phosphazenes and polymers thereof

    NASA Technical Reports Server (NTRS)

    Allcock, H. R.; Scopelianos, A. G. (Inventor)

    1984-01-01

    Carboranylmethylene-substituted cyclophosphazenes are described which can be thermally polymerized into carboranylmethylene-substituted phosphazene polymers. The polymers are useful as thermally stable coatings. Also, due to the characteristics of these polymers in acting as a ligand for transition metals, metalocarboranylmethylene phosphazene polymers are described which can act as immobilized catalyst systems, and are electrically conductive and superconductive.

  14. Phosphazene polymer containing composites and method for making phosphazene polymer containing composites

    SciTech Connect

    Allen, C.A.; Grey, A.E.; McCaffrey, R.R.; Simpson, B.M.; Stone, M.L.

    1990-12-31

    The object of the invention is to provide a composite material comprised of phosphazene polymer. A feature of phosphazene-containing composites is their superior stiffness, thermal stability, and hardness which is lacking in more typical composite constituents. An advantage of using phosphazene composites is a wider range of applications, including uses in harsh environments. Another object of the present invention provides a method for producing phosphazene-containing composite materials through a pultrusion process. In brief, these and other objects are achieved by a composite produced by first coating a reinforcing material with an inorganic phosphazene compound and then polymerizing the phosphazene compound so as to confer superior thermal, physical and chemical resistance qualities to the composite. 2 figs., 6 tabs.

  15. Hybrid phosphazene anodes for energy storage applications

    SciTech Connect

    Eric J. Dufek; Mark L. Stone; Kevin L. Gering; Frederick F. Stewart; David Jamison; Aaron D. Wilson; Lucia M. Petkovic; Mason K. Harrup; Harry W. Rollins

    2014-12-01

    The use of hybrid cyclic phosphazene polymer/graphite anodes, where the phosphazene serves as distributed loci for Li deposition, has been investigated. Capacity within the hybrid system was found to occur reversibly in distinct regions. At the most positive voltages, above 0.06 V vs Li/Li+, the capacity was associated mostly with Li+ intercalation into graphite. In the most negative region, deposition of Li within the polymer was the predominate mechanism. A transitional region is inferred by the data whereby bulk aggregation or clustering of Li atoms occurs in proximity to the phosphazene sites that then serve as a template for more widespread population of Li within the anode at higher voltages, akin to a nucleation process. In full cells with a mixed oxide cathode, controlling the extent of Li deposition by limiting the charging voltage to 4.45 V enabled repeated cycling with no loss in capacity. Capacities as high as 183 mAh g-1 have been achieved for systems containing as little as 10% graphite while retaining coulombic efficiencies of 98% over 50 cycles. This level of cycling equates to the deposition of 7.4 Li per cyclic phosphazene.

  16. Molecular structure, linear and nonlinear optical properties of some cyclic phosphazenes: A theoretical investigation

    NASA Astrophysics Data System (ADS)

    Hadji, Djebar; Rahmouni, Ali

    2016-02-01

    We report ab initio and density functional theory calculations of structural data, dipole moment, diagonal vibrational and electronic contributions to polarizability, vibrational and electronic contributions to first hyperpolarizability of some cyclic phosphazenes. The electronic structure of substituted cyclic phosphazenes has been investigated using Hartree-Fock and density functional theory. The vibrational and electronic contributions to polarizabilities and first hyperpolarizability of these molecules were calculated with HF method, and different DFT levels used the traditional B3LYP and PBE functional and the long-range corrected functional like Coulomb-attenuating method CAM-B3LYP, LC-BLYP and wB97XD used different basis sets. These cyclic phosphazenes adopts a planar structure. The chosen level of theory was found to describe satisfactory the molecular structure (r. m. s. of the relative deviations). The study reveals that the cyclic phosphazenes derivatives have large vibrational contribution to static first hyperpolarizability values. The results obtained from this work will provide into the electronic properties of this important class of inorganic polymers.

  17. Lithium Binding in Fluorinated Phosphazene Trimers

    SciTech Connect

    Michael T. Benson; Mason K. Harrup; Kevin L. Gering

    2013-02-01

    Density functional theory is used to model a series of cyclic phosphazenes, with and without coordinated Li+. Two pendant groups are used, ethoxy and 2,2,2-trifluoroethoxy, in varying combinations to generate phosphazenes with 0, 1, 2, 3, or 6 trifluoro groups. In all cases, Li+ sits in a pocket on the ring, always bonding to a ring nitrogen, and can be three- or four-coordinate, depending on the local environment. Three-coordinate occurs when no fluorines are close enough to interact, with the lithium bonding to a ring nitrogen and the two adjacent oxygens. When Li+ is four-coordinate, the bonding varies between the ring nitrogen, two adjacent oxygens, and one fluorine, or the ring nitrogen, one adjacent oxygen, and two fluorines. All of the possible symmetry unique structures have been calculated. The binding strength of Li+ steadily decreases, from 74.93 kcal/mol with no trifluoro groups, to 58.01 kcal/mol when 6 trifluoro groups are present. The decrease is attributed to the electron withdrawing effect of the trifluoro groups, and also to distortions in the geometry to accommodate Li-F interactions.

  18. Macromolecular Pt(IV) Prodrugs from Poly(organo)phosphazenes.

    PubMed

    Henke, Helena; Kryeziu, Kushtrim; Banfić, Jelena; Theiner, Sarah; Körner, Wilfried; Brüggemann, Oliver; Berger, Walter; Keppler, Bernhard K; Heffeter, Petra; Teasdale, Ian

    2016-08-01

    The preparation of novel macromolecular prodrugs via the conjugation of two platinum(IV) complexes to suitably functionalized poly(organo)phosphazenes is presented. The inorganic/organic polymers provide carriers with controlled dimensions due to the use of living cationic polymerization and allow the preparation of conjugates with excellent aqueous solubility but long-term hydrolytic degradability. The macromolecular Pt(IV) prodrugs are designed to undergo intracellular reduction and simultaneous release from the macromolecular carrier to present the active Pt(II) drug derivatives. In vitro investigations show a significantly enhanced intracellular uptake of Pt for the macromolecular prodrugs when compared to small molecule Pt complexes, which is also reflected in an increase in cytotoxicity. Interestingly, drug-resistant sublines also show a significantly smaller resistance against the conjugates compared to clinically established platinum drugs, indicating that an alternative uptake route of the Pt(IV) conjugates might also be able to overcome acquired resistance against Pt(II) drugs. In vivo studies of a selected conjugate show improved tumor shrinkage compared to the respective Pt(IV) complex. PMID:27169668

  19. Macromolecular Pt(IV) Prodrugs from Poly(organo)phosphazenes

    PubMed Central

    Banfić, Jelena; Theiner, Sarah; Körner, Wilfried; Brüggemann, Oliver; Berger, Walter; Keppler, Bernhard K.; Heffeter, Petra; Teasdale, Ian

    2016-01-01

    The preparation of novel macromolecular prodrugs via the conjugation of two platinum(IV) complexes to suitably functionalized poly(organo)phosphazenes is presented. The inorganic/organic polymers provide carriers with controlled dimensions due to the use of living cationic polymerization and allow the preparation of conjugates with excellent aqueous solubility but long-term hydrolytic degradability. The macromolecular Pt(IV) prodrugs are designed to undergo intracellular reduction and simultaneous release from the macromolecular carrier to present the active Pt(II) drug derivatives. In vitro investigations show a significantly enhanced intracellular uptake of Pt for the macromolecular prodrugs when compared to small molecule Pt complexes, which is also reflected in an increase in cytotoxicity. Interestingly, drug-resistant sublines also show a significantly smaller resistance against the conjugates compared to clinically established platinum drugs, indicating that an alternative uptake route of the Pt(IV) conjugates might also be able to overcome acquired resistance against Pt(II) drugs. In vivo studies of a selected conjugate show improved tumor shrinkage compared to the respective Pt(IV) complex. PMID:27169668

  20. Phosphazenes for energy production and storage: Applied and exploratory synthesis

    NASA Astrophysics Data System (ADS)

    Hess, Andrew R.

    This dissertation involves progress toward phosphazene-based ion conducting materials with a focus on structure-property relationships to improve these materials. This dissertation also includes some more fundamental exploratory syntheses to probe the limits of phosphazene chemistry and discover structure-property relationships that may be useful in designing compounds to fulfill important technical requirements. Chapter 1 provides a brief introduction to polymers and polyphosphazenes as well as ion-conducting materials and the contribution of polyphosphazene chemistry to that field. Chapter 1 also provides a brief introduction to some analytical techniques. Chapter 2 begins with the use of organophosphates as stand-alone non-volatile and fire-retardant liquid electrolyte media for dye sensitized solar cells (DSSCs) as well as their use as plasticizer in polymer gel electrolytes intended for application in lithium batteries. These organophosphates are the smallest phosphorus containing model molecules investigated in this dissertation. A homologous series of oligoalkyleneoxy substituted phosphates was synthesized and the effect of the substituent chain length on viscosity and conductivity was investigated. Small, test-scale DSSCs were constructed and showed promising results with overall cell efficiencies of up to 3.6% under un-optimized conditions. Conductivity measurements were performed on polymer gel-electrolytes based on poly[bis(2-(2-methoxyethoxy)ethoxy)phosphazene] (MEEP) plasticized with the phosphate with the best combination of properties, using a system loaded with lithium trifluoromethanesulfonate as the charge carrier. In chapter 3 the effect of the cation of the charge carrier species on the anionic conductivity of DSSC type electrolytes is evaluated using hexakis(2-(2-methoxyethoxy)ethoxy)cyclotriphosphazene (MEE-trimer) as a small molecule model for MEEP. The iodides of lithium, sodium, and ammonium as well as the ionic liquid, 1-propyl-3

  1. Phosphazenes: efficient organocatalysts for the catalytic hydrosilylation of carbon dioxide.

    PubMed

    Courtemanche, Marc-André; Légaré, Marc-André; Rochette, Étienne; Fontaine, Frédéric-Georges

    2015-04-21

    Phosphazene superbases are efficient organocatalysts for the metal-free catalytic hydrosilylation of carbon dioxide. They react with CO2 to form the respective phosphine oxides, but in the presence of hydrosilanes, CO2 can be selectively reduced to silyl formates, which can in turn be reduced to methoxysilanes by addition of an extra loading of silanes. Activities reach a TOF of 32 h(-1) with a TON of 759. It is also shown that unexpectedly, N,N-dimethylformamide can reduce CO2 to a mixture of silyl formates, acetals and methoxides in the absence of any catalyst. PMID:25791523

  2. Phosphorus-nitrogen compounds: Part 28. Syntheses, structural characterizations, antimicrobial and cytotoxic activities, and DNA interactions of new phosphazenes bearing vanillinato and pendant ferrocenyl groups

    NASA Astrophysics Data System (ADS)

    Tümer, Yasemin; Asmafiliz, Nuran; Kılıç, Zeynel; Hökelek, Tuncer; Yasemin Koç, L.; Açık, Leyla; Yola, Mehmet Lütfi; Solak, Ali Osman; Öner, Yağmur; Dündar, Devrim; Yavuz, Makbule

    2013-10-01

    The gradually Cl replacement reactions of spirocyclic mono (1 and 2) and bisferrocenyl cyclotriphosphazenes (3-5) with the potassium salt of 4-hydroxy-3-methoxybenzaldehyde (potassium vanillinate) gave mono (1a-5a), geminal (gem-1b-5b), non-geminal (cis-1b, cis-5b and trans-2b-5b), tri (1c-5c) and tetra-substituted phosphazenes (1d-5d). Some phosphazenes have stereogenic P-center(s). The chirality of 4c was verified using chiral HPLC column. Electrochemical behaviors were influenced only by the number of ferrocene groups, but not the length of the amine chains and the substituent(s). The structures of the new phosphazenes were determined by FTIR, MS, 1H, 13C and 31P NMR, HSQC and HMBC spectral data. The solid-state structures of cis-1b and 4d were examined by single crystal X-ray diffraction techniques. The twelve phosphazene derivatives were screened for antimicrobial activity and the compounds 5a, cis-1b and 2c exhibited the highest antibacterial activity against G(+) and G(-) bacteria. In addition, it was found that overall gem-1b inhibited the growth of Mycobacterium tuberculosis. The compounds 1d, 2d and 4d were tested in HeLa cancer cell lines. Among these compounds, 2d had cytotoxic effect on HeLa cell in the first 48 h. Moreover, interactions between compounds 2a, gem-1b, gem-2b, cis-1b, 2c, 3c, 4c, 5c, 1d, 2d and 4d, and pBR322 plasmid DNA were investigated.

  3. Computational Study of Intramolecular Heterocyclic Ring Formation with Cyclic Phosphazenes

    PubMed Central

    Miller, Whelton A.; Moore, Preston B.

    2015-01-01

    Polyphosphazenes, because of their unique properties, have generated many opportunities to explore a variety of applications. These applications include areas such as biomedical research (e.g. drug delivery) and material science (e.g. fire-resistant polymers). Phosphazenes potentially have more variations then benzene analogues because of different substitution patterns. Here we present A computational study of the chemical modifications to a group of cyclic phosphazenes mainly hexachlorophosphazene (PNCl2)3. This study focuses on the relative energies of reactivity of hexachlorophosphazene to understand their geometry and the complexes they likely form. We compare diols, amino alcohols, and diamines with a carbon linker of 1-7 atoms. These heteroatom chains are attached to a single phosphorus atom or adjoining phosphorus atoms to form ring structures of geminal, vicinal (cis), and vicinal (trans) moieties. We find that the reactivities of “heteroatom caps” are predicted to be O,O (diol) > N,O (amino alcohol) > N,N (diamine). These results can be used to predict energetics and thus the stability of new compounds for biomedical and industrial applications. PMID:26702403

  4. The mechanism of a phosphazene-phosphazane rearrangement.

    PubMed

    Hayes, Robert F; Allen, Christopher W

    2016-02-01

    The phosphazene-phosphazane rearrangement of N3P3Cl5O(CH2)2OC(=O)CMe=CH2 (8) has been examined in detail using one and two dimensional NMR ((31)P, (1)H) spectroscopy and mass spectrometry. The mixed phosphazene-phosphazane [NPCl2]2[N((CH2)2OC(=O)CMe=CH2)P(O)Cl] (14), [NPCl2]2[NHP(O)Cl] (13) and a two ring assembly [NPCl2]2[NP(O{(NPCl2)2(N((CH2)2OC(=O)CMe=CH2)P(O)}] (15) have all been detected in the product mixture. The rate of the rearrangement has been measured at five temperatures by (31)P and (1)H NMR. The reaction is first order in 8 (T1/2 at 111° is 4.65 hours). The activation enthalpy is positive and the activation entropy is negative. A mechanism involving competing intra and inter molecular processes which fits the product distribution and kinetic data has been proposed. Several other methyacrylphosphazenes were examined under the same thermolysis conditions. The rearrangement was observed and the rates obtained in cases where the (CH2)2 spacer unit of the methacrylate was replaced by linear and branched propyl units. The rearrangement was not observed when the methacrylate was appended to a spirocyclic unit, the spacer unit was extended to the n-butyl group and when the methacrylate unit was replaced by a methoxy group. These results are all consistent with the proposed mechanism. This investigation resolves conflicting results previous reported for the rearrangement. PMID:26416486

  5. Homogeneous nucleophilic radiofluorination and fluorination with phosphazene hydrofluorides.

    PubMed

    Mathiessen, Bente; Jensen, Andreas T I; Zhuravlev, Fedor

    2011-07-01

    A series of phosphazenium hydrofluorides, P(1)(tBu)·[(18/19)F]HF, P(1)(tOct)·[(18/19)F]HF, P(2)(Et)·[(18/19)F]HF, and P(4)(tBu)·[(18/19)F]HF, was synthesized. The radioactive phosphazenium [(18)F]hydrofluorides were obtained by the one-step formation and trapping of gaseous [(18)F]HF with the respective phosphazene bases. The [(19)F] isotopomers were prepared from the corresponding phosphazene bases and Et(3)N·3HF. Under the design of experiment (DoE)-optimized conditions, P(2)(Et)·HF and P(4)(tBu)·HF fluorinated alkyl chlorides, bromides, and pseudohalides in 76-98% yield, but gave lower yields with iodides and electron-deficient arenes. DoE models showed that fluorination can be performed in glass vessels, and that the reactivity of P(2)(Et)·HF and P(4)(tBu)·HF is dominated by solvent polarity but is insensitive to water to at least 2 equiv. In contrast, P(1)(tBu)·HF and P(1)(tOct)·HF were unstable towards autofluorolysis. DFT calculations were performed to rationalize this finding in terms of diminished steric bulk, higher Parr's electrophilicity, and chemical hardness of P(1)(R)H(+). The corresponding radiofluorination reaction gave no valid DoE model but displayed similar substrate scope. High specific activity and excellent radiochemical yields with various pseudohalides (81-91%) suggest that the proposed radiofluorination methodology can complement the current [(18)F]KF/Kryptofix methods, particularly in the areas for which nonpolar reaction conditions are required. PMID:21626586

  6. Control of Chemical, Thermal, and Gas Transport Properties in Dense Phosphazene Polymer Membranes.

    SciTech Connect

    Christopher J. Orme; Frederick F. Stewart; Mark L. Stone; Mason K. Harrup; Thomas A. Luther; Eric S. Peterson

    2005-10-01

    Polyphosphazenes are hybrid polymers having organic pendant groups attached to an inorganic backbone. Phosphazene polymers can be tailored to specific applications through the attachment of a variety of different pendant groups to the phosphazene backbone. Applications for which these polymers have proven useful include solid polymer electrolytes for batteries and fuel cells, as well as, membranes for gas and liquid separations. In past work, phosphazene polymers have been synthesized using mixtures of pendant groups with differing chemical affinities. Specific ratios of hydrophobic and hydrophilic pendant groups were placed on the phosphazene backbone with a goal of demonstrating control of solubility, and therefore chemical selectivity. In this work, a series of phosphazene homo-polymers were synthesized having varying amounts of hydrophobic and hydrophilic character on each individual pendant group. Polymers were synthesized having a hydrophilic portion next to the polymer backbone and the hydrophobic portion on the terminal end of the pendant group. The effects of these combined hydrophobic/hydrophilic pendant groups on polymer morphology and gas transport properties are presented. The following data will be addressed: thermal characterization, pure gas permeability on seven gases (Ar, H2, O2, N2, CO2, and CH4 ), and ideal selectivity for the gas pairs: O2/N2, H2/CO2, CO2/H2, CO2/CH4 and CO2/N2.

  7. Unsaturated phosphazenes as co-solvents for lithium-ion battery electrolytes

    NASA Astrophysics Data System (ADS)

    Harrup, Mason K.; Rollins, Harry W.; Jamison, David K.; Dufek, Eric J.; Gering, Kevin L.; Luther, Thomas A.

    2015-03-01

    This paper covers the synthesis and use of a related family of cyclic phosphazene solvents containing terminal unsaturations that are being considered as electrolyte additives in lithium-ion cells. A brief synopsis on the synthesis and purification of these compounds is given. Data will be presented that covers physical and chemical properties of the phosphazenes as well as the properties when blended at various levels with representative organic carbonate baseline solvents. Electrochemical cycling data will be presented using commercially available electrode couples as well as studies focusing on cell performance at early lifetime as well as after repeated cycles. Conclusions regarding the effect of the unsaturated phosphazene compounds and their interaction with various alkyl carbonates, and their effect on cell performance will be presented.

  8. Controlled ROP of β-butyrolactone simply mediated by amidine, guanidine, and phosphazene organocatalysts.

    PubMed

    Jaffredo, Cédric G; Carpentier, Jean-François; Guillaume, Sophie M

    2012-11-23

    Basic organocatalysts of the guanidine (1,5,7-triazabicyclo[4.4.0]dec-5-ene, TBD), amidine (1,8-diazabicyclo[5.4.0]-undec-7-ene, DBU), and phosphazene (2-tert-butylimino-2-diethylamino-1,3-dimethylperhydro-1,3,2diazaphosphorine, BEMP) type do effectively polymerize β-butyrolactone (BL). Poly(3-hydroxybutyrate)s (PHBs) with controlled molecular features, that is, controlled molar masses, narrow molar mass distributions, and well-defined functional end groups are thus formed at 60 °C from bulk monomer, with M(n,NMR) up to 21 500 g mol(-1). The formation of α,ω-guanidine/amidine/phosphazene,crotonate functionalized PHBs, as demonstrated by NMR, SEC, and MALDI-ToF mass spectrometry analyses, mechanistically suggests the formation of N-acyl-α,β-unsaturated propagating species that originate from 1:1 guanidine/amidine/phosphazene:BL adducts. PMID:22887774

  9. Unsaturated Phosphazenes as Co-Solvents for Lithium-Ion Battery Electrolytes

    SciTech Connect

    Harrup, Mason K; Rollins, Harry W.; Jamison, David K.; Dufek, Eric J; Gering, Kevin L; Luther, Thomas A

    2014-07-24

    This paper covers the synthesis and use of a related family of cyclic phosphazene solvents containing terminal unsaturations. A brief synopsis on the synthesis and purification of these compounds is given. Data will be presented that covers physical and chemical properties of the phosphazenes as well as the properties when blended at various level with representative organic carbonate baseline solvents. Cycling data will be presented using commercially available electrode couples (LRMR/C) as well as studies focusing on cell performance at early lifetime as well as after repeated cycles. Conclusions regarding the effect of the unsaturated phosphazene compounds and their interaction with various alkyl carbonates, and their effect on cell performance will be presented.

  10. Automated solid-phase radiofluorination using polymer-supported phosphazenes.

    PubMed

    Mathiessen, Bente; Zhuravlev, Fedor

    2013-01-01

    The polymer supported phosphazene bases PS-P₂(tBu) and the novel PS-P₂(PEG) allowed for efficient extraction of [¹⁸F]F⁻ from proton irradiated [¹⁸O]H₂O and subsequent radiofluorination of a broad range of substrates directly on the resin. The highest radiochemical yields were obtained with aliphatic sulfonates (69%) and bromides (42%); the total radiosynthesis time was 35-45 min. The multivariate analysis showed that the radiochemical yields and purities were controlled by the resin load, reaction temperature, and column packing effects. The resins could be reused several times with the same or different substrates. The fully automated on-column radiofluorination methodology was applied to the radiosynthesis of the important PET radiotracers [¹⁸F]FLT and [¹⁸F]FDG. The latter was produced with 40% yield on a 120 GBq scale and passed GMP-regulated quality control required for commercial production of [1¹⁸F]FDG. The combination of compact form factor, simplicity of [¹⁸F]F⁻ recovery and processing, and column reusability can make solid phase radiofluorination an attractive radiochemistry platform for the emerging dose-on-demand instruments for bedside production of PET radiotracers. PMID:23999726

  11. A Study of Novel Hexavalent Phosphazene Salts as Draw Solutes in Forward Osmosis

    SciTech Connect

    Mark L. Stone; Aaron D. Wilson; Mason K. Harrup; Frederick F. Stewart

    2013-03-01

    Two novel multi-valent salts based on phosphazene chemistry have been synthesized and characterized as forward osmosis (FO) draw solutes. Commercially obtained hexachlorocyclotriphosphazene was reacted with the sodium salt of 4-ethylhydroxybenzoate to yield hexa(4-ethylcarboxylatophenoxy)phosphazene. Hydrolysis, followed by and neutralization with NaOH or LiOH, of the resulting acidic moieties yielded water soluble sodium and lithium phosphazene salts, respectively. Degrees of dissociation were determined through osmometry over the range of 0.05-0.5 m, giving degrees of 3.08-4.95 per mole, suggesting a high osmotic potential. The Li salt was found to be more ionized in solution than the sodium salt, and this was reflected in FO experiments where the Li salt gave higher initial fluxes (~ 7 L/m2h) as compared to the sodium salt (~6 L/m2h) at identical 0.07 m draw solution concentrations at 30 °C. Longer term experiments revealed no detectable degradation of the salts; however some hydrolysis of the cellulose acetate membrane was observed, presumably due to the pH of the phosphazene salt draw solution (pH = ~8).

  12. Water Transport Polymers -- Structure/Property Relationships of a Series of Phosphazene Polymers

    SciTech Connect

    Christopher J. Orme; Eric S. Peterson; William F. Bauer; Frederick F. Stewart; Mason K. Harrup; Thomas A. Luther; John R. Klaehn; John E. Wey

    2010-01-01

    A study was undertaken to explore the water passing properties of a series of phosphazene polymers versus attached pendant group structure. Pendant groups containing different numbers ethyleneoxy groups were synthetically attached to the backbone of phosphazene polymers. Phosphazene polymers facilitate these types of studies because during their synthesis the polymer backbone is formed first and then the desired pendant groups are attached through nucleophilic substitution. For these studies, four polymer series were synthesized and tested for their water passing properties. The polymers contained different amounts of ethyleneoxy units. Two polymer families were synthesized and compared in this work. The critical difference in these two series is that one contained pendant groups with aromatic rings, in addition to the oligioethyleneoxy moieties, while the other does not. Polymers with phenyl group-containing pendant groups exhibited poor water permeability if they possessed fewer than six ethyleneoxy units. Polymers with more than six ethyleneoxy units inserted between the phenyl ring (tail) and the polymeric backbone, exhibited reasonable water permeability. Two additional series of mixed pendant group polymers were synthesized and the water passing properties of the phosphazenes varied in proportion to the hydrophilic to hydrophobic balance induced by each individual pendant group. A final study, polymers with shorter pendant groups, is shown to fully demonstrate the effect of pendant group on water permeability. These studies suggest that the polyphosphazenes may be tailored for specific water passing applications.

  13. Phenalene-phosphazene complexes: Effect of exocyclic charge densities on the cyclotriphosphazene ring system

    SciTech Connect

    Haddon, R.C.; Chichester-Hicks, S.V.; Mayo, S.L.

    1988-06-01

    The synthesis and properties of a new series of 1,9-diamino-substituted phenalene complexes of the cyclotriphosphazene ring system is described. One of the compounds is shown to be amphoteric, and this behavior allows an examination of the response of the phosphazene linkage to variations in exocyclic charge density at the spiro center in a plane perpendicular to the cyclotriphosphazene ring system. /sup 31/P NMR spectroscopy indicates that substituent lone pairs with this orientation are not effective in long-range delocalization within the phosphazene linkage (in accord with their theoretical model of spiro delocalization). An x-ray crystal structure of one compound (7) identifies the presence of clathrated molecules of chloroform together with doubly hydrogen-bonded pairs of the phenalene-phosphazene complexes in the lattice. Crystal data for 7 (C/sub 13/H/sub 8/Cl/sub 4/N/sub 5/P/sub 3/ /times/ CHCl/sub 3/): monoclinic space group P2/sub 1//c, a = 12.401 (4) /angstrom/, b = 28.404 (6) /angstrom/, c = 12.962 (3) /angstrom/, /beta/ = 91.76 (2)/degree/, V = 4564 (2) /angstrom//sup 3/, Z = 8, R = 0.050 for 4525 reflections. 24 references, 3 figures, 7 tables.

  14. Phosphazene Based Additives for Improvement of Safety and Battery Lifetimes in Lithium-Ion Batteries

    SciTech Connect

    Mason K Harrup; Kevin L Gering; Harry W Rollins; Sergiy V Sazhin; Michael T Benson; David K Jamison; Christopher J Michelbacher

    2011-10-01

    There need to be significant improvements made in lithium-ion battery technology, principally in the areas of safety and useful lifetimes to truly enable widespread adoption of large format batteries for the electrification of the light transportation fleet. In order to effect the transition to lithium ion technology in a timely fashion, one promising next step is through improvements to the electrolyte in the form of novel additives that simultaneously improve safety and useful lifetimes without impairing performance characteristics over wide temperature and cycle duty ranges. Recent efforts in our laboratory have been focused on the development of such additives with all the requisite properties enumerated above. We present the results of the study of novel phosphazene based electrolytes additives.

  15. Fluorinated Phosphazene Co-solvents for Improved Thermal and Safety Performance in Lithium-Ion Battery Electrolytes

    SciTech Connect

    Harry W. Rollins; Mason K. Harrup; Eric J. Dufek; David K. Jamison; Sergiy V. Sazhin; Kevin L. Gering; Dayna L. Daubaras

    2014-10-01

    The safety of lithium-ion batteries is coming under increased scrutiny as they are being adopted for large format applications especially in the vehicle transportation industry and for grid-scale energy storage. The primary short-comings of lithium-ion batteries are the flammability of the liquid electrolyte and sensitivity to high voltage and elevated temperatures. We have synthesized a series of non-flammable fluorinated phosphazene liquids and blended them with conventional carbonate solvents. While the use of these phosphazenes as standalone electrolytes is highly desirable, they simply do not satisfy all of the many requirements that must be met such as high LiPF6 solubility and low viscosity, thus we have used them as additives and co-solvents in blends with typical carbonates. The physical and electrochemical properties of the electrolyte blends were characterized, and then the blends were used to build 2032-type coin cells which were evaluated at constant current cycling rates from C/10 to C/1. We have evaluated the performance of the electrolytes by determining the conductivity, viscosity, flash point, vapor pressure, thermal stability, electrochemical window, cell cycling data, and the ability to form solid electrolyte interphase (SEI) films. This paper presents our results on a series of chemically similar fluorinated cyclic phosphazene trimers, the FM series, which has exhibited numerous beneficial effects on battery performance, lifetimes, and safety aspects.

  16. Preparation of Coaxial-Electrospun Poly[bis(p-methylphenoxy)]phosphazene Nanofiber Membrane for Enzyme Immobilization

    PubMed Central

    Wang, Shu-Gen; Jiang, Xin; Chen, Peng-Cheng; Yu, An-Guo; Huang, Xiao-Jun

    2012-01-01

    A core/sheath nanofiber membrane with poly[bis(p-methylphenoxy)]phosphazene (PMPPh) as the sheath and easily spinnable polyacrylonitrile (PAN) as the core was prepared via a coaxial electrospinning process. Field-emission scanning electron microscopy and transmission electron microscopy were used to characterize the morphology of the nanofiber membrane. It was found that the concentration of the PAN spinning solution and the ratio of the core/sheath solution flow rates played a decisive role in the coaxial electrospinning process. In addition, the stabilized core/sheath PMPPh nanofiber membrane was investigated as a support for enzyme immobilization because of its excellent biocompatibility, high surface/volume ratio, and large porosity. Lipase from Candida rugosa was immobilized on the nanofiber membrane by adsorption. The properties of the immobilized lipase on the polyphosphazene nanofiber membrane were studied and compared with those of a PAN nanofiber membrane. The results showed that the adsorption capacity (20.4 ± 2.7 mg/g) and activity retention (63.7%) of the immobilized lipase on the polyphosphazene nanofiber membrane were higher than those on the PAN membrane. PMID:23203055

  17. Peripheral nerve repair using a poly(organo)phosphazene tubular prosthesis.

    PubMed

    Langone, F; Lora, S; Veronese, F M; Caliceti, P; Parnigotto, P P; Valenti, F; Palma, G

    1995-03-01

    Nerve regeneration experiments were carried out using tubular nerve guides of poly[(ethylalanato)1.4(imidazolyl)0.6phosphazene] (PEIP). By means of in vivo tests, this polymer was found to be biodegradable and transformed into harmless products. The tubular nerve guides were prepared by deposition of the dissolved polymer on a glass capillary tube, followed by evaporation of the solvent (methylene dichloride). After transectioning, rat sciatic nerve stumps were immediately sutured into the ends of 10-mm-long polymer tubes. On removal of the prosthesis, after implantation for 45 d, a tissue cable was found bridging the nerve stumps in all cases. Histological analysis revealed that the tissue cable was essentially composed of a regenerated nerve fibre bundle. A parallel series of experiments was undertaken to compare the use of silicone tubes that are not biodegradable and are most frequently used for studies of nerve regeneration with tubulization techniques. The advantages of biodegradable PEIP tubular nerve guides used for peripheral nerve repair are discussed. PMID:7662819

  18. Characterization of 2-(2-Methoxyethoxy)ethanol Substituted Phosphazene Polymers Using Pervaporation, Solubility Parameters and Sorption Studies

    SciTech Connect

    Orme, Christopher Joseph; Klaehn, John Ray; Harrup, Mason Kurt; Lash, Robert Paul; Stewart, Frederick Forrest

    2005-05-01

    Two linear phosphazene polymers were synthesized with differing amounts of hydrophilic 2-(2-methoxyethoxy)ethanol (MEE) and hydrophobic 4-methoxyphenol (MEOP) substituted on the backbone. These high polymers were cast into membranes and their permeability to water, methanol, ethanol, and 2-propanol was evaluated as a function of temperature. An additional polymer with a low content of MEE was studied for water permeation and was characterized by trace flux. At higher levels of MEE on the backbone, fluxes of all solvents increased. Solubility also was found to increase with increasing MEE content for all solvents except water. Unexpectedly, water was found to be less soluble in the higher MEE polymer, although higher membrane fluxes were observed. Diffusion coefficients showed the following trend: methanol 2-propanol > ethanol water. Finally, the affinity of solvents and polymers was discussed in terms of Hansen solubility parameters.

  19. Design, synthesis, and characterization of new phosphazene related materials, and study the structure property correlations

    NASA Astrophysics Data System (ADS)

    Tian, Zhicheng

    various gelation rates depending on the polymer structures and the concentrations. The rheological measurements of the supramolecular hydrogels indicate a fast gelation process and flowable character under a large stain. Chapter 4 outlines the preparation of a number of amphiphilic diblock copolymers based on poly[bis(trifluoroethoxy)phosphazene] (TFE) as the hydrophobic block and poly(dimethylaminoethylmethacrylate) (PDMAEMA) as the hydrophilic block. The TFE block was synthesized first by the controlled living cationic polymerization of a phosphoranimine, followed by replacement of all the chlorine atoms using sodium trifluoroethoxide. To allow for the growth of the PDMAEMA block, 3-azidopropyl-2-bromo-2-methylpropanoate, an atom transfer radical polymerization (ATRP) initiator, was grafted onto the endcap of the TFE block via the 'click' reaction followed by the ATRP of 2-(dimethylamino)ethyl methacrylate (DMAEMA). Chapter 5 is a report on the design and assembly of polyphosphazene materials based on the non-covalent "host--guest" interactions either at the terminus of the polymeric main-chains or the pendant side-chains. The supramolecular interaction at the main chain terminus was used to produce amphiphilic palm-tree like pseudo-block copolymers via host-guest interactions between an adamantane end-functionalized polyphosphazene and a 4-armed beta-cyclodextrin (beta-CD) initiated poly[poly(ethylene glycol) methyl ether methacylate] branched-star type polymer. The formation of micelles of the obtained amphiphiles was analyzed by fluorescence technique, dynamic light scattering, transmission electron microscopy, and atomic force microscopy. Chapter 6 is an investigation of the influence of bulky fluoroalkoxy side groups on the properties of polyphosphazenes. A new series of mixed-substituent high polymeric poly(fluoroalkoxyphosphazenes) containing trifluoroethoxy and branched fluoroalkoxy side groups was synthesized and characterized by NMR and GPC methods. These

  20. Galactosylated poly(2-(2-aminoethyoxy)ethoxy)phosphazene/DNA complex nanoparticles: in vitro and in vivo evaluation for gene delivery.

    PubMed

    Yang, Yongxin; Zhang, Zhiwen; Chen, Lingli; Gu, Wangwen; Li, Yaping

    2010-04-12

    To achieve efficient gene delivery to the tumor after intravenous administration, biodegradable poly(2-(2-aminoethyoxy)ethoxy)phosphazene (PAEP) was modified by lactobionic acid, bearing a galactose group as a targeting ligand. Galactosylated poly(2-(2-aminoethyoxy)ethoxy)phosphazene (Gal-PAEP) with 4.9% substitution degree of galactose could condense pDNA into nanoparticles with a size around 130 nm at the polymer/DNA ratio (N/P) of 2-40. For BEL-7402 cells, the in vitro transfection efficiency of gal-PAEP/DNA complex nanoparticles (gal-PACNs) was much higher than that of the PAEP/DNA complex nanoparticles (PACNs). MTT assay indicated that the cytotoxicity of PACNs significantly decreased after conjugating with the galactose moiety. Gal-PACNs displayed the selective gene expression in the tumor and liver with relatively low gene expression in the lung or other organs compared with PACNs. These results suggested that gal-PACNs could be a promising targeting gene carrier to deliver a therapeutic gene in future. PMID:20302354

  1. Section IV.D.3 for DOE 2013 Annual Report: Novel Phosphazene-based Compounds to Enhance Safety and Stability of Cell Chemistries for High Voltage Applications (INL)

    SciTech Connect

    Kevin L. Gering; Mason K. Harrup; Eric J. Dufek; Sergiy V. Sazhin; Harry W. Rollins; David K. Jamison; Fred F. Stewart; John Burba

    2013-09-01

    Electrolytes play a central role in performance and aging in most electrochemical systems. As automotive and grid applications place a higher reliance on electrochemical stored energy, it becomes more urgent to have electrolyte components that enable optimal battery performance while promoting battery safety and longevity. Safety remains a foremost concern for widespread utilization of Li-ion technology in electric-drive vehicles, especially as the focus turns to higher voltage systems (5V). This work capitalizes on the long established INL expertise regarding phosphazene chemistry, aimed at battery-viable compounds for electrolytes and electrodes that are highly tolerant to abusive conditions. This report showcases our 2013 work for the DOE applied battery research (ABR) program, wherein testing results are summarized for INL electrolytes and alternative anode materials.

  2. Phosphazene Polymers Containing Carborane

    NASA Technical Reports Server (NTRS)

    Fewell, L. L.; Parker, J. A.; Basi, R. J.

    1986-01-01

    Addition of carborane increases thermal stability. Carborane-substituted polyphosphazenes prepared by thermal polymerization of phenylcarbonyl-pentachlorocyclotriphosphazene followed by reaction with sodium trifluoroethoxide to replace remaining chlorine atoms with trifluoroethoxy groups. Improved polymers offer high char yields and resistance to hydrolysis.

  3. Osteocompatibility evaluation of poly(glycine ethyl ester-co-alanine ethyl ester)phosphazene with honeycomb-patterned surface topography.

    PubMed

    Duan, Shun; Yang, Xiaoping; Mao, Jifu; Qi, Bing; Cai, Qing; Shen, Hong; Yang, Fei; Deng, Xuliang; Wang, Shenguo

    2013-02-01

    Biodegradable amino acid ester-substituted polyphosphazenes are unique biomaterials for tissue engineering. Considering the surface properties as topography and chemical composition having vital roles in regulating cellular response, in this study, a kind of micropatterned polyphosphazene films were prepared and subjected to osteoblasts culture. Briefly, poly(glycine ethyl ester-co-alanine ethyl ester)phosphazene (PGAP) was synthesized, and its solution in chloroform was cast under high (80%) or low (20%) environmental humidity. Honeycomb-patterned or flat PGAP films were resulted. By analyzing with scanning electron microscope, atomic force microscope, X-ray photoelectron spectroscope, and water contact angle measurement, the honeycomb-patterned PGAP films demonstrated higher surface roughness, phosphorous and nitrogen content, and hydrophilicity than the flat one. Although the initial cell attachment and proliferation on PGAP films were inferior to those on conventional poly(lactic-co-glycolic acid) films, P-containing PGAP was a sort of bone-binding bioactive polymer. With these alternations, honeycomb-patterned PGAP films had accordingly enhanced protein adsorption and apatite deposition in simulated body fluid and showed great advantages in promoting osteogenous differentiation. The results suggested a potential way to make polyphosphazenes as good choices for bone tissue regeneration by increasing their surface roughness and phosphorous content. PMID:22733644

  4. "Stereoscopic" 2D super-microporous phosphazene-based covalent organic framework: Design, synthesis and selective sorption towards uranium at high acidic condition.

    PubMed

    Zhang, Shuang; Zhao, Xiaosheng; Li, Bo; Bai, Chiyao; Li, Yang; Wang, Lei; Wen, Rui; Zhang, Meicheng; Ma, Lijian; Li, Shoujian

    2016-08-15

    So far, only five primary elements (C, H, O, N and B) and two types of spatial configuration (C2-C4, C6 and Td) are reported to build the monomers for synthesis of covalent organic frameworks (COFs), which have partially limited the route selection for accessing COFs with new topological structure and novel properties. Here, we reported the design and synthesis of a new "stereoscopic" 2D super-microporous phosphazene-based covalent organic framework (MPCOF) by using hexachorocyclotriphosphazene (a P-containing monomer in a C3-like spatial configuration) and p-phenylenediamine (a linker). The as-synthesized MPCOF shows high crystallinity, relatively high heat and acid stability and distinctive super-microporous structure with narrow pore-size distributions ranging from 1.0-2.1nm. The results of batch sorption experiments with a multi-ion solution containing 12 co-existing cations show that in the pH range of 1-2.5, MPCOF exhibits excellent separation efficiency for uranium with adsorption capacity more than 71mg/g and selectivity up to record-breaking 92%, and furthermore, an unreported sorption capacity (>50mg/g) and selectivity (>60%) were obtained under strong acidic condition (1M HNO3). Studies on sorption mechanism indicate that the uranium separation by MPCOF in acidic solution is realized mainly through both intra-particle diffusion and size-sieving effect. PMID:27107239

  5. Phosphazene-based ionic liquids: synthesis, temperature-dependent viscosity, and effect as additives in water lubrication of silicon nitride ceramics.

    PubMed

    Omotowa, Bamidele A; Phillips, Benjamin S; Zabinski, Jeffery S; Shreeve, Jean'ne M

    2004-08-23

    Phosphazene rings with (dimethylamino)ethoxy (1, 2), pyridylmethoxy (3), or (dimethylamino)propoxy (4) chains were synthesized and quaternized at the substitutent nitrogen by treatment with methyl iodide at 35 degrees C over 3-6 h to give polyiodo salts, 5-8. Subsequent metathesis with LiN(SO(2)CF(3))(2) or NaBF(4) gave the respective ionic salts, 9-13. The amide salts, 9-12, were viscous liquids with pour points at 55-100 degrees C, and the tetrafluoroborate salt, 13, was a solid, mp 168 degrees C. The compositions of 2 and 5-13 were confirmed by elemental analysis and spectroscopic methods. Compounds 1, 2, and 4 were viscous liquids (d(25) = 1.67 g cm(-3); eta(25) = 0.76-1.56 mPa s(-1) ) with pour points at approximately 15 degrees C. The solid polyquaternary salts, 5-8, melted at 130-194 degrees C. The ionic liquids, 9-12, had an average density of approximately 1.73 g cm(-3) at 25 degrees C, and viscosities (25 degrees C) ranged between 68.3 and 139.2 mPa s(-1). A plot of the viscosities of 9-12 vs temperature revealed an almost linear correlation between 55 and 120 degrees C. Friction and wear properties of water with 0.25 wt % of 9-12 as boundary lubricant additives were evaluated on Si(3)N(4)/Si(3)N(4) ceramic interfaces. The most significant observation is that they caused a decrease in the running-in period. PMID:15310229

  6. Phosphorus-nitrogen compounds. Part 20: Fully substituted spiro-cyclotriphosphazenic lariat (PNP-pivot) ether derivatives

    NASA Astrophysics Data System (ADS)

    Okumuş, Aytuğ; Bilge, Selen; Kılıç, Zeynel; Öztürk, Aslı; Hökelek, Tuncer; Yılmaz, Filiz

    2010-08-01

    The condensation reactions of partly substituted spiro-cyclotriphosphazenic lariat (PNP-pivot) ethers, N 3P 3[( o-NHPhO) 2R]Cl 4 [where R = -CH 2CH 2- ( 1) and -CH 2CH 2OCH 2CH 2- ( 2)] with morpholine and 1,4-dioxa-8-azaspiro[4,5]decane (DASD) produce fully substituted morpholino ( 3 and 4) and 1,4-dioxa-8-azaspiro[4,5]deca ( 5 and 6) phosphazenes. These are the new examples of the spiro-cyclophosphazenic lariat ether derivatives with N 2O x ( x = 2 and 3) donor type containing 11- and 14-membered macrocycles. The solid state structures of 3, 5 and 6 have been determined by X-ray diffraction techniques. Compound 3 has intermolecular N-H…O hydrogen bond, compound 5 has intra- and intermolecular N-H…O hydrogen bonds, while compound 6 has intramolecular N-H…O and O-H…N and intermolecular N-H…O and O-H…O hydrogen bonds. The correlations of the endocyclic ( α) and exocyclic ( α') NPN bond angles with δP spiro values are investigated. The structural investigations of 3- 6 have been verified by elemental analyses, MS, FTIR, 1H, 13C and 31P NMR, DEPT and HETCOR techniques.

  7. Complex derivatives

    NASA Astrophysics Data System (ADS)

    Battiston, Stefano; Caldarelli, Guido; Georg, Co-Pierre; May, Robert; Stiglitz, Joseph

    2013-03-01

    The intrinsic complexity of the financial derivatives market has emerged as both an incentive to engage in it, and a key source of its inherent instability. Regulators now faced with the challenge of taming this beast may find inspiration in the budding science of complex systems.

  8. Synthesis and thermal stability of carborane-containing phosphazenes

    NASA Technical Reports Server (NTRS)

    Fewell, L. L.; Parker, J. A.; Basi, R. J.

    1983-01-01

    Carborane-substituted polyphosphazenes were prepared by the thermal polymerization of phenyl-carboranyl pentachlorocylotriphosphazene. Successive isothermal vacuum pyrolyses were conducted on the polymer and examined for structural changes by infrared spectroscopy. The degradation products were ascertained by gas chromatography-mass spectrometric analysis. It was found that the presence of the carborane group improves the thermal stability of the polymer by retarding the ring-chain equilibrium processes of decomposition. Previously announced in STAR as A83-21034

  9. Synthesis and thermal stability of carborane containing phosphazenes

    NASA Technical Reports Server (NTRS)

    Fewell, L. L.; Basi, R. J.; Parker, J. A.

    1983-01-01

    Carborane substituted polyphosphazenes were prepared by the thermal polymerization of phenyl-carboranyl penta chlorocyclotriphosphazene. Successive isothermal vacuum pyrolyses were conducted on the polymer and examined for structural changes by infrared spectroscopy. The degradation products were ascertained by gas chromatography-mass spectrometric analysis. It was found that the presence of the carborane group improves the thermal stability of the polymer by retarding the ring chain equilibrium processes of decomposition.

  10. Synthetic Bioluminescent Coelenterazine Derivatives.

    PubMed

    Nishihara, Ryo; Citterio, Daniel; Suzuki, Koji

    2016-01-01

    The development of coelenterazine (CTZ) derivatives resulting in superior optical characteristics is an efficient method to extend the range of its possible applications. Here, we describe the synthesis of three C-6 substituted CTZ derivatives retaining the recognition by Renilla luciferase (RLuc) and its derivatives. The novel derivatives are useful as bright blue-shifted CTZ derivatives, which can be used as an alternative to hitherto reported compound DeepBlueC™. PMID:27424892

  11. Direct Density Derivative Estimation.

    PubMed

    Sasaki, Hiroaki; Noh, Yung-Kyun; Niu, Gang; Sugiyama, Masashi

    2016-06-01

    Estimating the derivatives of probability density functions is an essential step in statistical data analysis. A naive approach to estimate the derivatives is to first perform density estimation and then compute its derivatives. However, this approach can be unreliable because a good density estimator does not necessarily mean a good density derivative estimator. To cope with this problem, in this letter, we propose a novel method that directly estimates density derivatives without going through density estimation. The proposed method provides computationally efficient estimation for the derivatives of any order on multidimensional data with a hyperparameter tuning method and achieves the optimal parametric convergence rate. We further discuss an extension of the proposed method by applying regularized multitask learning and a general framework for density derivative estimation based on Bregman divergences. Applications of the proposed method to nonparametric Kullback-Leibler divergence approximation and bandwidth matrix selection in kernel density estimation are also explored. PMID:27140943

  12. Endohedral Metallofullerene Derivatives

    NASA Technical Reports Server (NTRS)

    Dorn, Harry C. (Inventor); Iezzi, Erick B. (Inventor); Duchamp, James (Inventor)

    2008-01-01

    Trimetallic nitride endohedral metallofullerene derivatives and their preparation are described. The trimetallic nitride endohedral metallofullerene derivatives have the general formula A(sub 3-n)X(sub n)@C(sub m)(R) where n ranges from 0 to 3, A and X may be trivalent metals and may be either rare earth metal or group IIIB metals, m is between about 60 and about 200, and R is preferably an organic group. Derivatives where the R group forms cyclized derivatives with the fullerene cage are also described.

  13. DERIVE in Slovenian Schools.

    ERIC Educational Resources Information Center

    Lokar, Matija

    This paper describes several projects concerning the use of the DERIVE programming language for symbolic computation in Slovenia. The main topics discussed include preparing books and materials using DERIVE in Slovenian language, and a survey on the use of programs for symbolic computation by mathematics teachers in Slovenian secondary schools.…

  14. Irregularities in Imperfective Derivation

    ERIC Educational Resources Information Center

    Levin, Maurice I.

    1977-01-01

    This article discusses presentation of Russian conjugation via the one-stem system advocated by Lipson and Townsend, and attempts a more unified and complete presentation of irregularities in imperfect derivation. Two major irregularities are occurrence of an unexpected suffix and unpredictable alternation in the root of the derived imperfective.…

  15. The Dangers of Derivatives.

    ERIC Educational Resources Information Center

    Blumenstyk, Goldie

    1994-01-01

    Heavy investment in derivatives, whose value derives from the price movement of some underlying security, has meant heavy losses for some colleges and universities despite the fact that institutional investors are required to assure that they understand the risks of such investment. (MSE)

  16. The azobenzene derivatives

    NASA Astrophysics Data System (ADS)

    Ionita, Ionica; Radulescu, Cristiana; Poinescu, Aurora Anca; Anghelina, Florina Violeta; Bunghez, Raluca; Ion, Rodica-Mariana

    2015-02-01

    Azobenzene derivatives constitute a group of dyes which have photochromic properties and have been investigated as promising systems for diverse applications in the unconventional optic area, their properties can be moulded with help of light.

  17. Synthesis of phenoxatellurine derivatives

    SciTech Connect

    Maksimenko, A.A.; Rivkin, B.B.; Sadekov, I.D.; Minkin, V.I.

    1985-12-01

    The reaction of dimedon enol acetate with tellurium tetrachloride gives derivatives of octahydrophenoxatellurine. The reaction of cyclohexanone enol acetate and methyl ethyl ketone with tellurium tetrachloride or aryltellurium trichloride gives the respective organotellurium trichloride and diorganotellurium dichloride.

  18. Synthesis, structural characterization and dielectric behavior of new oxime-cyclotriphosphazene derivatives

    NASA Astrophysics Data System (ADS)

    Koran, Kenan; Özen, Furkan; Biryan, Fatih; Görgülü, Ahmet Orhan

    2016-02-01

    The cyclotriphosphazene compound (2) bearing formyl groups as side groups was obtained from the reaction of 2,2-Dichloro-4,4,6,6-bis[spiro(2‧,2″-dioxy-1‧,1″-biphenylyl)]cyclotriphosphazene (1) with 4-hydroxy-3-methoxybenzaldehyde in the presence K2CO3 in tetrahydrofuran. Oxime-cyclotriphosphazene compound (3) was synthesized from the reaction of compound 2 with hydroxylamine hydrochloride in pyridine. The synthesized oxime-phosphazene compound (3) was reacted with alkyl and acyl halides. As a results, the cyclotriphosphazene compounds (1-10) bearing oxime ether and ester as side groups were obtained. The chemical structures of these compounds (1-10) were determined by elemental analysis, FT-IR, 1H, 13C and 31P NMR spectroscopic methods. Dielectric constant, dielectric loss factors and conductivity properties of cyclotriphosphazene compounds were measured over the frequency range from 100 Hz to 2 kHz at 25 °C and compared with each other. It is found that ester substituted cyclotriphosphazenes have higher dielectric constant. Our study suggests that these phosphazenes promising candidate materials in multifunctional optoelectronic devices.

  19. Semisynthetic Derivatives of Epothilones

    NASA Astrophysics Data System (ADS)

    Altmann, Karl-Heinz

    Semisynthetic derivatives of natural products traditionally occupy a prominent space in natural-product-based drug discovery (1, 2). As many biologically active natural products exhibit a high degree of structural complexity (3), the chemical derivatization of material isolated from natural sources often represents the only feasible means (or at least the only economically viable approach) to explore structure-activity-relationships (SAR) and to produce analogs with more favorable pharmacokinetic and pharmacological properties than the natural product lead. Examples of clinically important drugs that are semisynthetic derivatives of natural products exist in virtually all disease areas (1, 2); in the treatment of cancer this includes compounds such as etoposide or teniposide (derived from podophyllotoxin) (4-6), irinotecan and topotecan (derived from camptothecin) (7-9), or docetaxel (derived from 10-deacetylbaccatin III) (10, 11). Even for taxol (11), which is a natural product (12), the sustained supply of sufficient quantities of material for widespread clinical use could only be secured through the development of a semisynthetic production process from another natural product, namely, 10-deacetylbaccatin III (13). In light of these facts, it is not surprising that semisynthesis approaches have also featured prominently in the elucidation of the SAR for epothilones and in the discovery of a number of clinical development candidates.

  20. Ferroelectricity in corundum derivatives

    NASA Astrophysics Data System (ADS)

    Ye, Meng; Vanderbilt, David

    The search for new ferroelectric (FE) materials holds promise for broadening our understanding of FE mechanisms and extending the range of application of FE materials. The known FE materials LiNbO3 can be regarded as derived from the A2O3 corundum structure with cation ordering. Here we consider more general binary (AB O3) and ternary (A2 BB' O6) corundum derivatives as an extended class of potential FE materials, motivated by the fact that some members of this class have recently been synthesized. There are four structure types for these corundum derivatives, and the number of cation combinations is enormous, but in many cases the energy barriers for polarization reversal may be too large to allow FE behavior. Here we present a first-principles study of the polar structure, coherent FE barrier, and domain-wall switching barrier for a representative set of polar corundum derivatives, allowing us to identify several potentially new FE materials. We also discuss the conditions under which ferroelectricity is compatible with magnetic ordering. Finally, we identify several empirical measures that can provide a rule of thumb for estimating the barrier energies. Our results should assist in the experimental search for new FE materials in the corundum derivative family. This work is supported by ONR Grant No. N-00014-12-1-1035.

  1. Myeloid derived suppressor cells

    PubMed Central

    Waldron, Todd J.; Quatromoni, Jon G.; Karakasheva, Tatiana A.; Singhal, Sunil; Rustgi, Anil K.

    2013-01-01

    The goal of achieving measurable response with cancer immunotherapy requires counteracting the immunosuppressive characteristics of tumors. One of the mechanisms that tumors utilize to escape immunosurveillance is the activation of myeloid derived suppressor cells (MDSCs). Upon activation by tumor-derived signals, MDSCs inhibit the ability of the host to mount an anti-tumor immune response via their capacity to suppress both the innate and adaptive immune systems. Despite their relatively recent discovery and characterization, anti-MDSC agents have been identified, which may improve immunotherapy efficacy. PMID:23734336

  2. Oxygenated Derivatives of Hydrocarbons

    Technology Transfer Automated Retrieval System (TEKTRAN)

    For the book entitled “Insect Hydrocarbons: Biology, Biochemistry and Chemical Ecology”, this chapter presents a comprehensive review of the occurrence, structure and function of oxygenated derivatives of hydrocarbons. The book chapter focuses on the occurrence, structural identification and functi...

  3. 78 FR 32191 - Derivatives

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-29

    ... alternatives. \\5\\ 71 FR 5155 (February 2, 2012). C. 1998 IRPS This proposed rule is consistent with a 1998... promulgation of this proposed rule. \\7\\ 76 FR 37030 (June 24, 2011). First, the Board asked if it should... derivatives transactions independently. \\9\\ 77 FR 5416 (Feb. 3, 2012). Question One. The Board asked if...

  4. Biotechnology and derived products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Microorganisms able to infect and kill insect pests, metabolites from plants and microorganisms, and transgenic crops are biotechnologically derived products that are being promoted for use to control insect pests in lieu of chemical insecticides. Products based on these technologies effectively co...

  5. Ferroelectricity in corundum derivatives

    NASA Astrophysics Data System (ADS)

    Ye, Meng; Vanderbilt, David

    2016-04-01

    The search for new ferroelectric (FE) materials holds promise for broadening our understanding of FE mechanisms and extending the range of application of FE materials. Here we investigate a class of A B O3 and A2B B'O6 materials that can be derived from the X2O3 corundum structure by mixing two or three ordered cations on the X site. Most such corundum derivatives have a polar structure, but it is unclear whether the polarization is reversible, which is a requirement for a FE material. In this paper, we propose a method to study the FE reversal path of materials in the corundum derivative family. We first categorize the corundum derivatives into four classes and show that only two of these allow for the possibility of FE reversal. We then calculate the energy profile and energy barrier of the FE reversal path using first-principles density functional methods with a structural constraint. Furthermore, we identify several empirical measures that can provide a rule of thumb for estimating the energy barriers. Finally, the conditions under which the magnetic ordering is compatible with ferroelectricity are determined. These results lead us to predict several potentially new FE materials.

  6. Derived enriched uranium market

    SciTech Connect

    Rutkowski, E.

    1996-12-01

    The potential impact on the uranium market of highly enriched uranium from nuclear weapons dismantling in the Russian Federation and the USA is analyzed. Uranium supply, conversion, and enrichment factors are outlined for each country; inventories are also listed. The enrichment component and conversion components are expected to cause little disruption to uranium markets. The uranium component of Russian derived enriched uranium hexafluoride is unresolved; US legislation places constraints on its introduction into the US market.

  7. Space Derived Air Monitor

    NASA Technical Reports Server (NTRS)

    1983-01-01

    COPAMS, Commonwealth of Pennsylvania Air Monitoring System, derives from technology involved in building unmanned spacecraft. The Nimbus spacecraft carried experimental sensors to measure temperature, pressure, ozone, and water vapor, and instruments for studying solar radiation and telemetry. The process which relayed these findings to Earth formed the basis for COPAMS. The COPAMS system consists of data acquisition units which measure and record pollution level, and sense wind speed and direction, etc. The findings are relayed to a central station where the information is computerized. The system is automatic and supplemented by PAQSS, PA Air Quality Surveillance System.

  8. In defense of derivations

    NASA Astrophysics Data System (ADS)

    Mungan, Carl E.

    2016-05-01

    At the 2015 AAPT Summer Meeting, I presented four derivations of the formula for motional emf. Such physics derivations involve the construction of explanatory frameworks involving diagrams and mathematical models. Although textbooks devote considerable space to such explanations, many teachers and students spend their time on worksheets, end-of-chapter problems, and the like. The book is reduced to a bank of solved (i.e., example) and unsolved (i.e., homework) questions, along with equations in colored boxes that presumably are to be used to answer those questions. Such an approach encourages fragmentation of knowledge, the view that there is only one right answer to a problem with the goal of physics being to find that answer (neatly boxed of course), and the inability to reason about even a slightly different (much less a novel) situation. If we are to develop scientific literacy, significant course time must be devoted to explaining the structure of and support for the models and equations we use.

  9. Acquiring Knowledge of Derived Nominals and Derived Adjectives in Context

    ERIC Educational Resources Information Center

    Marinellie, Sally A.; Kneile, Lynn A.

    2012-01-01

    Purpose: This research investigated children's ability to acquire semantic and syntactic knowledge of derived nominals and derived adjectives in the context of short passages. The study also investigated the relation of morphological awareness and the ability to acquire knowledge of derived words in context. Method: A total of 106 children in…

  10. Experts' Understanding of Partial Derivatives Using the Partial Derivative Machine

    ERIC Educational Resources Information Center

    Roundy, David; Weber, Eric; Dray, Tevian; Bajracharya, Rabindra R.; Dorko, Allison; Smith, Emily M.; Manogue, Corinne A.

    2015-01-01

    Partial derivatives are used in a variety of different ways within physics. Thermodynamics, in particular, uses partial derivatives in ways that students often find especially confusing. We are at the beginning of a study of the teaching of partial derivatives, with a goal of better aligning the teaching of multivariable calculus with the needs of…

  11. Algae Derived Biofuel

    SciTech Connect

    Jahan, Kauser

    2015-03-31

    One of the most promising fuel alternatives is algae biodiesel. Algae reproduce quickly, produce oils more efficiently than crop plants, and require relatively few nutrients for growth. These nutrients can potentially be derived from inexpensive waste sources such as flue gas and wastewater, providing a mutual benefit of helping to mitigate carbon dioxide waste. Algae can also be grown on land unsuitable for agricultural purposes, eliminating competition with food sources. This project focused on cultivating select algae species under various environmental conditions to optimize oil yield. Membrane studies were also conducted to transfer carbon di-oxide more efficiently. An LCA study was also conducted to investigate the energy intensive steps in algae cultivation.

  12. 6-Bromocholesterol derivatives

    SciTech Connect

    Flanagan, R.J.

    1984-02-07

    Novel 6-bromo derivatives of cholesterol have the formula 3-(R-O-),6-BR,17-((H3C-)2-HC-H2C-H2C-H2C-HC(-CH3)-)-ESTR-5-ENE Such compounds are prepared from the known 6-iodocholesterol by treatment with cuprous bromide. These compounds, labelled with radioisotopes of Br-82 or Br-77, are localized in the adrenal, mammary and ovary tissue of female mammals and in the adrenal or prostate tissue of males when administered to such individuals. This provides a method for imaging adrenal, ovary or prostate tissue which is superior to use of the prior art 6-iodo-cholesterol.

  13. Experts' understanding of partial derivatives using the partial derivative machine

    NASA Astrophysics Data System (ADS)

    Roundy, David; Weber, Eric; Dray, Tevian; Bajracharya, Rabindra R.; Dorko, Allison; Smith, Emily M.; Manogue, Corinne A.

    2015-12-01

    [This paper is part of the Focused Collection on Upper Division Physics Courses.] Partial derivatives are used in a variety of different ways within physics. Thermodynamics, in particular, uses partial derivatives in ways that students often find especially confusing. We are at the beginning of a study of the teaching of partial derivatives, with a goal of better aligning the teaching of multivariable calculus with the needs of students in STEM disciplines. In this paper, we report on an initial study of expert understanding of partial derivatives across three disciplines: physics, engineering, and mathematics. We report on the central research question of how disciplinary experts understand partial derivatives, and how their concept images of partial derivatives differ, with a focus on experimentally measured quantities. Using the partial derivative machine (PDM), we probed expert understanding of partial derivatives in an experimental context without a known functional form. In particular, we investigated which representations were cued by the experts' interactions with the PDM. Whereas the physicists and engineers were quick to use measurements to find a numeric approximation for a derivative, the mathematicians repeatedly returned to speculation as to the functional form; although they were comfortable drawing qualitative conclusions about the system from measurements, they were reluctant to approximate the derivative through measurement. On a theoretical front, we found ways in which existing frameworks for the concept of derivative could be expanded to include numerical approximation.

  14. DRS: Derivational Reasoning System

    NASA Technical Reports Server (NTRS)

    Bose, Bhaskar

    1995-01-01

    The high reliability requirements for airborne systems requires fault-tolerant architectures to address failures in the presence of physical faults, and the elimination of design flaws during the specification and validation phase of the design cycle. Although much progress has been made in developing methods to address physical faults, design flaws remain a serious problem. Formal methods provides a mathematical basis for removing design flaws from digital systems. DRS (Derivational Reasoning System) is a formal design tool based on advanced research in mathematical modeling and formal synthesis. The system implements a basic design algebra for synthesizing digital circuit descriptions from high level functional specifications. DRS incorporates an executable specification language, a set of correctness preserving transformations, verification interface, and a logic synthesis interface, making it a powerful tool for realizing hardware from abstract specifications. DRS integrates recent advances in transformational reasoning, automated theorem proving and high-level CAD synthesis systems in order to provide enhanced reliability in designs with reduced time and cost.

  15. Piroxicam derivatives THz classification

    NASA Astrophysics Data System (ADS)

    Sterczewski, Lukasz A.; Grzelczak, Michal P.; Nowak, Kacper; Szlachetko, Bogusław; Plinska, Stanislawa; Szczesniak-Siega, Berenika; Malinka, Wieslaw; Plinski, Edward F.

    2016-02-01

    In this paper we report a new approach to linking the terahertz spectral shapes of drug candidates having a similar molecular structure to their chemical and physical parameters. We examined 27 newly-synthesized derivatives of a well-known nonsteroidal anti-inflammatory drug Piroxicam used for treatment of inflammatory arthritis and chemoprevention of colon cancer. The testing was carried out by means of terahertz pulsed spectroscopy (TPS). Using chemometric techniques we evaluated their spectral similarity in the terahertz range and attempted to link the position on the principal component analysis (PCA) score map to the similarity of molecular descriptors. A simplified spectral model preserved 75% and 85.1% of the variance in 2 and 3 dimensions respectively, compared to the input 1137. We have found that in 85% of the investigated samples a similarity of the physical and chemical parameters corresponds to a similarity in the terahertz spectra. The effects of data preprocessing on the generated maps are also discussed. The technique presented can support the choice of the most promising drug candidates for clinical trials in pharmacological research.

  16. Vaccine-derived polioviruses.

    PubMed

    Burns, Cara C; Diop, Ousmane M; Sutter, Roland W; Kew, Olen M

    2014-11-01

    The attenuated oral poliovirus vaccine (OPV) has many properties favoring its use in polio eradication: ease of administration, efficient induction of intestinal immunity, induction of durable humoral immunity, and low cost. Despite these advantages, OPV has the disadvantage of genetic instability, resulting in rare and sporadic cases of vaccine-associated paralytic poliomyelitis (VAPP) and the emergence of genetically divergent vaccine-derived polioviruses (VDPVs). Whereas VAPP is an adverse event following exposure to OPV, VDPVs are polioviruses whose genetic properties indicate prolonged replication or transmission. Three categories of VDPVs are recognized: (1) circulating VDPVs (cVDPVs) from outbreaks in settings of low OPV coverage, (2) immunodeficiency-associated VDPVs (iVDPVs) from individuals with primary immunodeficiencies, and (3) ambiguous VDPVs (aVDPVs), which cannot be definitively assigned to either of the first 2 categories. Because most VDPVs are type 2, the World Health Organization's plans call for coordinated worldwide replacement of trivalent OPV with bivalent OPV containing poliovirus types 1 and 3. PMID:25316847

  17. Synthesis of 2-carbethoxybenzofuran derivatives

    SciTech Connect

    Prewysz-Kwinto, A.

    1987-12-01

    A mixture of 3-formyl and 3-acetoxymethyl derivatives is formed in the oxidation of 2-carbethoxy-3-methyl-7-ethylbenzofuran with selenium dioxide. Reduction with lithium aluminum hydride gives 2,3-dihydroxymethyl derivatives, which are converted to 2,3-diformyl derivatives by successive oxidation. A number of derivatives of 3-methyl-7-ethylbenzofurancarboxylic acid were obtained. The PMR spectra of solutions of the compounds in CDCl/sub 3/ were recorded with a Tesla B-487 spectrometer (80 Hz) with hexamethyldisiloxane (HMDS) as the internal standard. The IR spectra of KBr pellets of the compounds were obtained with a UR-10 spectrometer.

  18. Buckybowls: Corannulene and Its Derivatives.

    PubMed

    Li, Xu; Kang, Feiyu; Inagaki, Michio

    2016-06-01

    Corannulene, a kind of bowl like polycyclic aromatic hydrocarbon (PAH), whose molecule is composed of a central pentagon and five closely adjacent hexagons on the pentagon's five sides, has received great scientific interest among research groups. In this review, the syntheses, characteristic molecule structure and properties of corannulene are clarified, as well as its derivatives with different substituted groups, fused derivatives, metal complex, and derivatives for host guest chemistry. On the basis of reviewing the applications and properties of corannulene together with its derivatives, the potential applications in hydrogen storage and lithium storage were highlighted and prospected. PMID:27136669

  19. Alternative algebras admitting derivations with invertible values and invertible derivations

    NASA Astrophysics Data System (ADS)

    Kaygorodov, I. B.; Popov, Yu S.

    2014-10-01

    We prove an analogue of the Bergen-Herstein-Lanski theorem for alternative algebras: describe all alternative algebras that admit derivations with invertible values. We also prove an analogue of Moens' theorem for alternative algebras (a finite-dimensional alternative algebra over a field of characteristic zero is nilpotent if and only if it admits an invertible Leibniz derivation).

  20. Bone Marrow Derived Eosinophil Cultures

    PubMed Central

    Lu, Thomas X.; Rothenberg, Marc E.

    2016-01-01

    Eosinophils are multifunctional effector cells implicated in the pathogenesis of a variety of diseases including asthma, eosinophil gastrointestinal disorders and helminth infection. Mouse bone marrow derived progenitor cells can be differentiated into eosinophils following IL-5 exposure. These bone marrow derived eosinophils are fully differentiated at the end of a 14 day culture based on morphology and expression of molecular markers.

  1. Quinazoline derivatives: synthesis and bioactivities

    PubMed Central

    2013-01-01

    Owing to the significant biological activities, quinazoline derivatives have drawn more and more attention in the synthesis and bioactivities research. This review summarizes the recent advances in the synthesis and biological activities investigations of quinazoline derivatives. According to the main method the authors adopted in their research design, those synthetic methods were divided into five main classifications, including Aza-reaction, Microwave-assisted reaction, Metal-mediated reaction, Ultrasound-promoted reaction and Phase-transfer catalysis reaction. The biological activities of the synthesized quinazoline derivatives also are discussed. PMID:23731671

  2. Elevation Derivatives for National Applications

    USGS Publications Warehouse

    U.S. Geological Survey

    2005-01-01

    The Elevation Derivatives for National Applications (EDNA) project is a multi-agency effort to develop standard topographically derived layers for use in hydrologic and environmental modeling. The EDNA takes advantage of the seamless and filtered characteristics for the National Elevation Dataset (NED) to create a hydrologically conditioned Digital Elevation Model (DEM) useful for modeling applications. The goals of the project are to create a hydrologically conditioned DEM and systematically extract a set of standard derivatives that can be used to facilitate data integration with other U.S. Geological Survey (USGS) framework data sets such as the National Hydrography Dataset (NHD) and the Watershed Boundaries Dataset (WBD).

  3. Phosphazene Silicate Nanocomposites. A Survey of Materials Properties and Synthetic Methods Using New Catalysts

    SciTech Connect

    Harrup, Mason Kurt; Wertsching, Alan Kevin; Stewart, Frederick Forrest

    2000-03-01

    In the ceramics community, manipulation of synthetic conditions such as the choice of acid, base or ionic species as catalysts, aging of precursor solutions, and choice of sintering temperatures in the formation of silicate networks are known to produce radically different glass and ceramic morphologies.1 Implementation of these approaches has been attempted for some organic polymer based hybrid nanocomposites2 but not for polyphosphazene silicate composites. The desire to create unique and novel network morphologies became the impetus for establishing new catalysis protocols. The surprising inability to reproduce the mechanical properties of a well-established benchmark composite material from the literature,3 was one principal driver that initiated this in-depth investigation into the roles that the nature and amount of catalysts play in the production and physical properties of these composites.

  4. Microscopic derivation of discrete hydrodynamics.

    PubMed

    Español, Pep; Anero, Jesús G; Zúñiga, Ignacio

    2009-12-28

    By using the standard theory of coarse graining based on Zwanzig's projection operator, we derive the dynamic equations for discrete hydrodynamic variables. These hydrodynamic variables are defined in terms of the Delaunay triangulation. The resulting microscopically derived equations can be understood, a posteriori, as a discretization on an arbitrary irregular grid of the Navier-Stokes equations. The microscopic derivation provides a set of discrete equations that exactly conserves mass, momentum, and energy and the dissipative part of the dynamics produces strict entropy increase. In addition, the microscopic derivation provides a practical implementation of thermal fluctuations in a way that the fluctuation-dissipation theorem is satisfied exactly. This paper points toward a close connection between coarse-graining procedures from microscopic dynamics and discretization schemes for partial differential equations. PMID:20059064

  5. What is a fractional derivative?

    NASA Astrophysics Data System (ADS)

    Ortigueira, Manuel D.; Tenreiro Machado, J. A.

    2015-07-01

    This paper discusses the concepts underlying the formulation of operators capable of being interpreted as fractional derivatives or fractional integrals. Two criteria for required by a fractional operator are formulated. The Grünwald-Letnikov, Riemann-Liouville and Caputo fractional derivatives and the Riesz potential are accessed in the light of the proposed criteria. A Leibniz rule is also obtained for the Riesz potential.

  6. Fullerene Derivatives for Medical Applications

    NASA Astrophysics Data System (ADS)

    Hirsch, Andreas

    2005-09-01

    Water-soluble fullerene derivatives have a potential for a variety of medical applications. This is due to the unique structural-, electronic and chemical properties of the fullerene core. The biological properties of suitably functionalized fullerenes range from enzyme inhibition/receptor binding, anticancer and antiviral activity, cell signalling, DNA- and genomic applications, photodynamic activation and most importantly antioxidant properties. This review focusses on the anti-HIV and antioxidant properties of a couple of water soluble fullerene derivatives.

  7. Bioactive steroid derivatives and butyrolactone derivatives from a gorgonian-derived Aspergillus sp. fungus.

    PubMed

    Chen, Min; Wang, Kai-Ling; Liu, Min; She, Zhi-Gang; Wang, Chang-Yun

    2015-09-01

    Six steroid derivatives, 1-6, and five butyrolactone derivatives, 7-11, were isolated from the fermentation broth of a gorgonian-derived Aspergillus sp. fungus. Their structures were elucidated on the basis of NMR and MS spectral data. Compound 1 is a new, highly conjugated steroid. The NMR and MS data of 7 and 8 are reported for the first time, as their structures were listed in SciFinder Scholar with no associated reference. Compounds 1, 4, 5, and 8-11 inhibited the larval settlement of barnacle Balanus amphitrite with EC50 values ranging from 0.63 to 18.4 μg ml(-1) . Butyrolactone derivatives 7 and 8 showed pronounced antibacterial activities against Staphylococcus aureus with the same MIC values as the positive control ciprofloxacin (MIC 1.56 μM for all three compounds). PMID:26363883

  8. Nucleoside derivatives from the marine-derived fungus Aspergillus versicolor.

    PubMed

    Chen, Min; Fu, Xiu-Mei; Kong, Chui-Jian; Wang, Chang-Yun

    2014-01-01

    Four nucleoside derivatives (1-4) were isolated from the fungus Aspergillus versicolor derived from the gorgonian Dichotella gemmacea collected in the South China Sea. Their structures were elucidated by comprehensive spectroscopic method of NMR and MS analysis. All isolated metabolites were evaluated for their cytotoxicity, antibacterial activity and lethality towards brine shrimp Artemia salina. Compounds 1/2 exhibited selective antibacterial activity against Staphylococcus epidermidis with an MIC value of 12.5 μM. It should be noted that 1 and 2, whose structures were listed in SciFinder Scholar, had no associated reference. This is the first report about their isolation, structure elucidation and biological activities. PMID:24670197

  9. 12 CFR 390.352 - Financial derivatives.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 5 2012-01-01 2012-01-01 false Financial derivatives. 390.352 Section 390.352... Financial derivatives. (a) What is a financial derivative? A financial derivative is a financial contract... common types of financial derivatives are futures, forward commitments, options, and swaps. A...

  10. 12 CFR 390.352 - Financial derivatives.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 5 2013-01-01 2013-01-01 false Financial derivatives. 390.352 Section 390.352... Financial derivatives. (a) What is a financial derivative? A financial derivative is a financial contract... common types of financial derivatives are futures, forward commitments, options, and swaps. A...

  11. Sol-gel derived sorbents

    DOEpatents

    Sigman, Michael E.; Dindal, Amy B.

    2003-11-11

    Described is a method for producing copolymerized sol-gel derived sorbent particles for the production of copolymerized sol-gel derived sorbent material. The method for producing copolymerized sol-gel derived sorbent particles comprises adding a basic solution to an aqueous metal alkoxide mixture for a pH.ltoreq.8 to hydrolyze the metal alkoxides. Then, allowing the mixture to react at room temperature for a precalculated period of time for the mixture to undergo an increased in viscosity to obtain a desired pore size and surface area. The copolymerized mixture is then added to an immiscible, nonpolar solvent that has been heated to a sufficient temperature wherein the copolymerized mixture forms a solid upon the addition. The solid is recovered from the mixture, and is ready for use in an active sampling trap or activated for use in a passive sampling trap.

  12. Variational approach and deformed derivatives

    NASA Astrophysics Data System (ADS)

    Weberszpil, J.; Helayël-Neto, J. A.

    2016-05-01

    Recently, we have demonstrated that there exists a possible relationship between q-deformed algebras in two different contexts of Statistical Mechanics, namely, the Tsallis' framework and the Kaniadakis' scenario, with a local form of fractional-derivative operators for fractal media, the so-called Hausdorff derivatives, mapped into a continuous medium with a fractal measure. Here, in this paper, we present an extension of the traditional calculus of variations for systems containing deformed-derivatives embedded into the Lagrangian and the Lagrangian densities for classical and field systems. The results extend the classical Euler-Lagrange equations and the Hamiltonian formalism. The resulting dynamical equations seem to be compatible with those found in the literature, specially with mass-dependent and with nonlinear equations for systems in classical and quantum mechanics. Examples are presented to illustrate applications of the formulation. Also, the conserved ​Noether current is worked out.

  13. Relieving of Misconceptions of Derivative Concept with Derive

    ERIC Educational Resources Information Center

    Kaplan, Abdullah; Ozturk, Mesut; Ocal, Mehmet Fatih

    2015-01-01

    The purpose of this study is to determine students' learning levels in derivative subjects and their misconceptions. In addition, this study aims to compared to the effects of the computer based instruction and traditional instruction in resolving these misconceptions. For this purpose, 12th grade 70 students were chosen from high schools in Agri…

  14. Relieving of Misconceptions of Derivative Concept with Derive

    ERIC Educational Resources Information Center

    Kaplan, Abdullah; Ozturk, Mesut; Ocal, Mehmet Fatih

    2015-01-01

    The purpose of this study is to determine students' learning levels in derivative subjects and their misconceptions. In addition, this study aims to compared to the effects of the computer based instruction and traditional instruction in resolving these misconceptions. For this purpose, 70 12th grade students were chosen from high schools in Agri…

  15. Synthesis of 2-phosphaadamantane derivatives

    SciTech Connect

    Zemlyanoi, V.N.; Aleksandrov, A.M.; Kukhar', V.P.

    1986-05-20

    The authors describe the synthesis and properties of 2-phosphadamantane derivatives. For the synthesis of 2-phosphaadamantane derivatives they decided to use the methodology of the synthesis of 2-thiaadamantane. The IR spectra were determined on CHCl/sub 3/ solutions with a Specord 711R spectrometer, the PMR spectra were determined on Tesla BS-467 (60 MHz) and Bruker WP-200 (200 MHz) spectrometers, external standard hexamethyldisiloxane, the /sup 31/P NMR spectra were determined on Tesla BS-487 C (30 MHz) and Bruker WP-200 (81 MHz) spectrometers, external standard 85% phosphoric acid, and the mass spectra were determined on an MS-1302 spectrometer.

  16. Magnetic cellulose-derivative structures

    DOEpatents

    Walsh, Myles A.; Morris, Robert S.

    1986-09-16

    Structures to serve as selective magnetic sorbents are formed by dissolving a cellulose derivative such as cellulose triacetate in a solvent containing magnetic particles. The resulting solution is sprayed as a fine mist into a chamber containing a liquid coagulant such as n-hexane in which the cellulose derivative is insoluble but in which the coagulant is soluble or miscible. On contact with the coagulant, the mist forms free-flowing porous magnetic microspheric structures. These structures act as containers for the ion-selective or organic-selective sorption agent of choice. Some sorbtion agents can be incorporated during the manufacture of the structure.

  17. Empirically derived injury prevention rules.

    PubMed Central

    Peterson, L; Schick, B

    1993-01-01

    This study describes a set of empirically derived safety rules that if followed, would have prevented the occurrence of minor injuries. Epidemiologists have criticized behavioral interventions as increasing "safe" behavior but failing to demonstrate a decrease in injury. The present study documents retrospectively the link between safe behavior and injury. It demonstrates that these empirically derived rules are very similar to rules for the prevention of serious injury. The study also shows that these rules are not widely accepted and implemented by parents. Suggestions for future research in this area are advanced. PMID:8307829

  18. Characterization of Soluble Anthradithiophene Derivatives

    NASA Astrophysics Data System (ADS)

    Conrad, Brad; Chan, Calvin; Loth, Marsha; Anthony, John; Gundlach, David

    2010-03-01

    We will discuss the growth and electrical measurements of a newly developed, partially fluorinated anthradithiophene (F-ADT) derivative with tert-butyldiphenylsilyl (TBDMS) side groups. Single crystals of the material can be readily grown and device hole mobility is shown to exceed 0.05 cm^2/Vs with on/off ratios of 10^7. F- TBDMS ADT is also observed to be readily soluble with films spun cast onto surface treated SiO2 displaying a mobility >0.002 cm^2/Vs. These electrical measurements will be correlated with growth, morphology, and the performance of related F-ADT derivatives.

  19. Some Active Derivatives of Penicillin

    PubMed Central

    Brown, Loman D.; Zygmunt, Walter A.; Stavely, Homer E.

    1969-01-01

    The antibacterial activities of a number of amide derivatives of penicillin against both penicillin-sensitive and penicillin-resistant cultures were determined. Several of them were found to possess significant inhibitory activity against certain gram-positive bacteria. The amides, although resistant to the destructive action of β-lactamase, did not protect G in competitive experiments. One derivative, the O-benzylhydroxamide of penicillin G, was active against six or eight penicillin-resistant strains of Staphylococcus aureus (minimal inhibitory concentration, 0.2 μg/ml or less), but was found to have only a minimal in vivo activity against mouse Streptococcus infections. PMID:5780394

  20. Magnetic cellulose-derivative structures

    DOEpatents

    Walsh, M.A.; Morris, R.S.

    1986-09-16

    Structures to serve as selective magnetic sorbents are formed by dissolving a cellulose derivative such as cellulose triacetate in a solvent containing magnetic particles. The resulting solution is sprayed as a fine mist into a chamber containing a liquid coagulant such as n-hexane in which the cellulose derivative is insoluble but in which the coagulant is soluble or miscible. On contact with the coagulant, the mist forms free-flowing porous magnetic microspheric structures. These structures act as containers for the ion-selective or organic-selective sorption agent of choice. Some sorption agents can be incorporated during the manufacture of the structure. 3 figs.

  1. Informational derivation of quantum theory

    NASA Astrophysics Data System (ADS)

    Chiribella, Giulio; D'Ariano, Giacomo Mauro; Perinotti, Paolo

    2011-07-01

    We derive quantum theory from purely informational principles. Five elementary axioms—causality, perfect distinguishability, ideal compression, local distinguishability, and pure conditioning—define a broad class of theories of information processing that can be regarded as standard. One postulate—purification—singles out quantum theory within this class.

  2. Derivative couplings in massive bigravity

    NASA Astrophysics Data System (ADS)

    Gao, Xian; Heisenberg, Lavinia

    2016-03-01

    In this work we study the cosmological perturbations in massive bigravity in the presence of non-minimal derivative couplings. For this purpose we consider a specific subclass of Horndeski scalar-tensor interactions that live on the unique composite effective metric. For the viability of the model both metrics have to be dynamical. Nevertheless, the number of allowed kinetic terms is crucial. We adapt to the restriction of having one single kinetic term. After deriving the full set of equations of motion for flat Friedmann-Lemaitre-Robertson-Walker background, we study linear perturbations on top of it. We show explicitly that only four tensor, two vector and two scalar degrees of freedom propagate, one of which being the Horndeski scalar, while the Boulware-Deser ghost can be integrated out.

  3. Derivation of aerodynamic kernel functions

    NASA Technical Reports Server (NTRS)

    Dowell, E. H.; Ventres, C. S.

    1973-01-01

    The method of Fourier transforms is used to determine the kernel function which relates the pressure on a lifting surface to the prescribed downwash within the framework of Dowell's (1971) shear flow model. This model is intended to improve upon the potential flow aerodynamic model by allowing for the aerodynamic boundary layer effects neglected in the potential flow model. For simplicity, incompressible, steady flow is considered. The proposed method is illustrated by deriving known results from potential flow theory.

  4. Position Estimation Using Image Derivative

    NASA Technical Reports Server (NTRS)

    Mortari, Daniele; deDilectis, Francesco; Zanetti, Renato

    2015-01-01

    This paper describes an image processing algorithm to process Moon and/or Earth images. The theory presented is based on the fact that Moon hard edge points are characterized by the highest values of the image derivative. Outliers are eliminated by two sequential filters. Moon center and radius are then estimated by nonlinear least-squares using circular sigmoid functions. The proposed image processing has been applied and validated using real and synthetic Moon images.

  5. 12 CFR 563.172 - Financial derivatives.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 6 2012-01-01 2012-01-01 false Financial derivatives. 563.172 Section 563.172...-OPERATIONS Financial Management Policies § 563.172 Financial derivatives. (a) What is a financial derivative? A financial derivative is a financial contract whose value depends on the value of one or...

  6. 12 CFR 563.172 - Financial derivatives.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 6 2014-01-01 2012-01-01 true Financial derivatives. 563.172 Section 563.172...-OPERATIONS Financial Management Policies § 563.172 Financial derivatives. (a) What is a financial derivative? A financial derivative is a financial contract whose value depends on the value of one or...

  7. 12 CFR 563.172 - Financial derivatives.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 5 2011-01-01 2011-01-01 false Financial derivatives. 563.172 Section 563.172...-OPERATIONS Financial Management Policies § 563.172 Financial derivatives. (a) What is a financial derivative? A financial derivative is a financial contract whose value depends on the value of one or...

  8. 12 CFR 563.172 - Financial derivatives.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 6 2013-01-01 2012-01-01 true Financial derivatives. 563.172 Section 563.172...-OPERATIONS Financial Management Policies § 563.172 Financial derivatives. (a) What is a financial derivative? A financial derivative is a financial contract whose value depends on the value of one or...

  9. 12 CFR 163.172 - Financial derivatives.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 1 2012-01-01 2012-01-01 false Financial derivatives. 163.172 Section 163.172...-OPERATIONS Financial Management Policies § 163.172 Financial derivatives. (a) What is a financial derivative? A financial derivative is a financial contract whose value depends on the value of one or...

  10. Stable Hemiaminals: 2-Aminopyrimidine Derivatives.

    PubMed

    Kwiecień, Anna; Ciunik, Zbigniew

    2015-01-01

    Stable hemiaminals can be obtained in the one-pot reaction between 2-aminopyrimidine and nitrobenzaldehyde derivatives. Ten new hemiaminals have been obtained, six of them in crystal state. The molecular stability of these intermediates results from the presence of both electron-withdrawing nitro groups as substituents on the phenyl ring and pyrimidine ring, so no further stabilisation by intramolecular interaction is required. Hemiaminal molecules possess a tetrahedral carbon atom constituting a stereogenic centre. As the result of crystallisation in centrosymmetric space groups both enantiomers are present in the crystal structure. PMID:26258772

  11. Asymptotic vacua with higher derivatives

    NASA Astrophysics Data System (ADS)

    Cotsakis, Spiros; Kadry, Seifedine; Kolionis, Georgios; Tsokaros, Antonios

    2016-04-01

    We study limits of vacuum, isotropic universes in the full, effective, four-dimensional theory with higher derivatives. We show that all flat vacua as well as general curved ones are globally attracted by the standard, square root scaling solution at early times. Open vacua asymptote to horizon-free, Milne states in both directions while closed universes exhibit more complex logarithmic singularities, starting from initial data sets of a possibly smaller dimension. We also discuss the relation of our results to the asymptotic stability of the passage through the singularity in ekpyrotic and cyclic cosmologies.

  12. Iron and iron derived radicals

    SciTech Connect

    Borg, D.C.; Schaich, K.M.

    1987-04-01

    We have discussed some reactions of iron and iron-derived oxygen radicals that may be important in the production or treatment of tissue injury. Our conclusions challenge, to some extent, the usual lines of thought in this field of research. Insofar as they are born out by subsequent developments, the lessons they teach are two: Think fastexclamation Think smallexclamation In other words, think of the many fast reactions that can rapidly alter the production and fate of highly reactive intermediates, and when considering the impact of competitive reactions on such species, think how they affect the microenvironment (on the molecular scale) ''seen'' by each reactive molecule. 21 refs., 3 figs., 1 tab.

  13. Binder enhanced refuse derived fuel

    DOEpatents

    Daugherty, Kenneth E.; Venables, Barney J.; Ohlsson, Oscar O.

    1996-01-01

    A refuse derived fuel (RDF) pellet having about 11% or more particulate calcium hydroxide which is utilized in a combustionable mixture. The pellets are used in a particulate fuel bring a mixture of 10% or more, on a heat equivalent basis, of the RDF pellet which contains calcium hydroxide as a binder, with 50% or more, on a heat equivalent basis, of a sulphur containing coal. Combustion of the mixture is effective to produce an effluent gas from the combustion zone having a reduced SO.sub.2 and polycyclic aromatic hydrocarbon content of effluent gas from similar combustion materials not containing the calcium hydroxide.

  14. Fourth order spatial derivative gravity

    SciTech Connect

    Bemfica, F. S.; Gomes, M.

    2011-10-15

    In this work, we study a modified theory of gravity that contains up to fourth order spatial derivatives as a model for the Horava-Lifshitz gravity. The propagator is evaluated and, as a result, one extra pole is obtained, corresponding to a spin-2 nonrelativistic massless particle, an extra term which jeopardizes renormalizability, besides the unexpected general relativity unmodified propagator. Then unitarity is proved at the tree level, where the general relativity pole has been shown to have no dynamics, remaining only the 2 degrees of freedom of the new pole. Next, the nonrelativistic effective potential is determined from a scattering process of two identical massive gravitationally interacting bosons. In this limit, Newton's potential is obtained, together with a Darwin-like term that comes from the extra nonpole term in the propagator. Regarding renormalizability, this extra term may be harmful by power counting, but it can be eliminated by adjusting the free parameters of the model. This adjustment is in accord with the detailed balance condition suggested in the literature and shows that the way in which extra spatial derivative terms are added is of fundamental importance.

  15. Fourth order spatial derivative gravity

    NASA Astrophysics Data System (ADS)

    Bemfica, F. S.; Gomes, M.

    2011-10-01

    In this work, we study a modified theory of gravity that contains up to fourth order spatial derivatives as a model for the Hořava-Lifshitz gravity. The propagator is evaluated and, as a result, one extra pole is obtained, corresponding to a spin-2 nonrelativistic massless particle, an extra term which jeopardizes renormalizability, besides the unexpected general relativity unmodified propagator. Then unitarity is proved at the tree level, where the general relativity pole has been shown to have no dynamics, remaining only the 2 degrees of freedom of the new pole. Next, the nonrelativistic effective potential is determined from a scattering process of two identical massive gravitationally interacting bosons. In this limit, Newton’s potential is obtained, together with a Darwin-like term that comes from the extra nonpole term in the propagator. Regarding renormalizability, this extra term may be harmful by power counting, but it can be eliminated by adjusting the free parameters of the model. This adjustment is in accord with the detailed balance condition suggested in the literature and shows that the way in which extra spatial derivative terms are added is of fundamental importance.

  16. Deriving Laws from Ordering Relations

    NASA Technical Reports Server (NTRS)

    Knuth, Kevin H.

    2004-01-01

    The effect of Richard T. Cox's contribution to probability theory was to generalize Boolean implication among logical statements to degrees of implication, which are manipulated using rules derived from consistency with Boolean algebra. These rules are known as the sum rule, the product rule and Bayes Theorem, and the measure resulting from this generalization is probability. In this paper, I will describe how Cox s technique can be further generalized to include other algebras and hence other problems in science and mathematics. The result is a methodology that can be used to generalize an algebra to a calculus by relying on consistency with order theory to derive the laws of the calculus. My goals are to clear up the mysteries as to why the same basic structure found in probability theory appears in other contexts, to better understand the foundations of probability theory, and to extend these ideas to other areas by developing new mathematics and new physics. The relevance of this methodology will be demonstrated using examples from probability theory, number theory, geometry, information theory, and quantum mechanics.

  17. Derivatives of Black Knight Technology

    NASA Astrophysics Data System (ADS)

    Hill, N.; Wright, D.

    This paper traces the line of descent from Black Knight to Black Arrow, and at the same time looks at various proposed projects, both civil and military, which were to be Black Knight derivatives, but which for one reason or another never saw the light of day. Research in this area is rather akin to anthropological work, tracing fossils from Homo erectus (Black Knight) to Homo sapiens (Black Arrow), knowing that a lot of the fossils found will not be on the direct line of descent, but represent branches that became extinct. This article attempts to cover designs, which, although they never made it to hardware, are none the less interesting technically, or shine light on the evolution of design philosophy.

  18. Food-derived immunomodulatory peptides.

    PubMed

    Santiago-López, Lourdes; Hernández-Mendoza, Adrián; Vallejo-Cordoba, Belinda; Mata-Haro, Verónica; González-Córdova, Aarón F

    2016-08-01

    Food proteins contain specific amino acid sequences within their structures that may positively impact bodily functions and have multiple immunomodulatory effects. The functional properties of these specific sequences, also referred to as bioactive peptides, are revealed only after the degradation of native proteins during digestion processes. Currently, milk proteins have been the most explored source of bioactive peptides, which presents an interesting opportunity for the dairy industry. However, plant- and animal-derived proteins have also been shown to be important sources of bioactive peptides. This review summarizes the in vitro and in vivo evidence of the role of various food proteins as sources of immunomodulatory peptides and discusses the possible pathways involving these properties. © 2016 Society of Chemical Industry. PMID:26940008

  19. Derivative Sign Patterns in Two Dimensions

    ERIC Educational Resources Information Center

    Schilling, Kenneth

    2013-01-01

    Given a function defined on a subset of the plane whose partial derivatives never change sign, the signs of the partial derivatives form a two-dimensional pattern. We explore what patterns are possible for various planar domains.

  20. 22 CFR 9.6 - Derivative classification.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... CFR 2001.22. (c) Department of State Classification Guide. The Department of State Classification... Foreign Relations DEPARTMENT OF STATE GENERAL SECURITY INFORMATION REGULATIONS § 9.6 Derivative...'s classified Web site....

  1. 22 CFR 9.6 - Derivative classification.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... CFR 2001.22. (c) Department of State Classification Guide. The Department of State Classification... Foreign Relations DEPARTMENT OF STATE GENERAL SECURITY INFORMATION REGULATIONS § 9.6 Derivative...'s classified Web site....

  2. 5 CFR 1312.7 - Derivative classification.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., DOWNGRADING, DECLASSIFICATION AND SAFEGUARDING OF NATIONAL SECURITY INFORMATION Classification and Declassification of National Security Information § 1312.7 Derivative classification. A derivative classification means that the information is in substance the same information that is currently classified, usually...

  3. 5 CFR 1312.7 - Derivative classification.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., DOWNGRADING, DECLASSIFICATION AND SAFEGUARDING OF NATIONAL SECURITY INFORMATION Classification and Declassification of National Security Information § 1312.7 Derivative classification. A derivative classification means that the information is in substance the same information that is currently classified, usually...

  4. 5 CFR 1312.7 - Derivative classification.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., DOWNGRADING, DECLASSIFICATION AND SAFEGUARDING OF NATIONAL SECURITY INFORMATION Classification and Declassification of National Security Information § 1312.7 Derivative classification. A derivative classification means that the information is in substance the same information that is currently classified, usually...

  5. 5 CFR 1312.7 - Derivative classification.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., DOWNGRADING, DECLASSIFICATION AND SAFEGUARDING OF NATIONAL SECURITY INFORMATION Classification and Declassification of National Security Information § 1312.7 Derivative classification. A derivative classification means that the information is in substance the same information that is currently classified, usually...

  6. 5 CFR 1312.7 - Derivative classification.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., DOWNGRADING, DECLASSIFICATION AND SAFEGUARDING OF NATIONAL SECURITY INFORMATION Classification and Declassification of National Security Information § 1312.7 Derivative classification. A derivative classification means that the information is in substance the same information that is currently classified, usually...

  7. Deriving Laws from Ordering Relations

    NASA Technical Reports Server (NTRS)

    Knuth, Kevin H.

    2003-01-01

    It took much effort in the early days of non-Euclidean geometry to break away from the mindset that all spaces are flat and that two distinct parallel lines do not cross. Up to that point, all that was known was Euclidean geometry, and it was difficult to imagine anything else. We have suffered a similar handicap brought on by the enormous relevance of Boolean algebra to the problems of our age-logic and set theory. Previously, I demonstrated that the algebra of questions is not Boolean, but rather is described by the free distributive algebra. To get to this stage took much effort, as many obstacles-most self-placed-had to be overcome. As Boolean algebras were all I had ever known, it was almost impossible for me to imagine working with an algebra where elements do not have complements. With this realization, it became very clear that the sum and product rules of probability theory at the most basic level had absolutely nothing to do with the Boolean algebra of logical statements. Instead, a measure of degree of inclusion can be invented for many different partially ordered sets, and the sum and product rules fall out of the associativity and distributivity of the algebra. To reinforce this very important idea, this paper will go over how these constructions are made, while focusing on the underlying assumptions. I will derive the sum and product rules for a distributive lattice in general and demonstrate how this leads to probability theory on the Boolean lattice and is related to the calculus of quantum mechanical amplitudes on the partially ordered set of experimental setups. I will also discuss the rules that can be derived from modular lattices and their relevance to the cross-ratio of projective geometry.

  8. Polymer-Derived Ceramic Fibers

    NASA Astrophysics Data System (ADS)

    Ichikawa, Hiroshi

    2016-07-01

    SiC-based ceramic fibers are derived from polycarbosilane or polymetallocarbosilane precursors and are classified into three groups according to their chemical composition, oxygen content, and C/Si atomic ratio. The first-generation fibers are Si-C-O (Nicalon) fibers and Si-Ti-C-O (Tyranno Lox M) fibers. Both fibers contain more than 10-wt% oxygen owing to oxidation during curing and lead to degradation in strength at temperatures exceeding 1,300°C. The maximum use temperature is 1,100°C. The second-generation fibers are SiC (Hi-Nicalon) fibers and Si-Zr-C-O (Tyranno ZMI) fibers. The oxygen content of these fibers is reduced to less than 1 wt% by electron beam irradiation curing in He. The thermal stability of these fibers is improved (they are stable up to 1,500°C), but their creep resistance is limited to a maximum of 1,150°C because their C/Si atomic ratio results in excess carbon. The third-generation fibers are stoichiometric SiC fibers, i.e., Hi-Nicalon Type S (hereafter Type S), Tyranno SA, and Sylramic™ fibers. They exhibit improved thermal stability and creep resistance up to 1,400°C. Stoichiometric SiC fibers meet many of the requirements for the use of ceramic matrix composites for high-temperature structural application. SiBN3C fibers derived from polyborosilazane also show promise for structural applications, remain in the amorphous state up to 1,800°C, and have good high-temperature creep resistance.

  9. Complex order fractional derivatives in viscoelasticity

    NASA Astrophysics Data System (ADS)

    Atanacković, Teodor M.; Konjik, Sanja; Pilipović, Stevan; Zorica, Dušan

    2016-06-01

    We introduce complex order fractional derivatives in models that describe viscoelastic materials. This cannot be carried out unrestrictedly, and therefore we derive, for the first time, real valued compatibility constraints, as well as physical constraints that lead to acceptable models. As a result, we introduce a new form of complex order fractional derivative. Also, we consider a fractional differential equation with complex derivatives, and study its solvability. Results obtained for stress relaxation and creep are illustrated by several numerical examples.

  10. 40 CFR 721.1820 - Bisphenol derivative.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Bisphenol derivative. 721.1820 Section... Substances § 721.1820 Bisphenol derivative. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as bisphenol derivative (PMN No. P-92-509)...

  11. 40 CFR 721.1820 - Bisphenol derivative.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Bisphenol derivative. 721.1820 Section... Substances § 721.1820 Bisphenol derivative. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as bisphenol derivative (PMN No. P-92-509)...

  12. 40 CFR 721.1820 - Bisphenol derivative.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Bisphenol derivative. 721.1820 Section... Substances § 721.1820 Bisphenol derivative. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as bisphenol derivative (PMN No. P-92-509)...

  13. Improved Second Derivative Test for Relative Extrema

    ERIC Educational Resources Information Center

    Wu, Yan

    2007-01-01

    In this note, a modified Second Derivative Test is introduced for the relative extrema of a single variable function. This improved test overcomes the difficulty of the second derivative vanishing at the critical point, while in contrast the traditional test fails for this case. A proof for this improved Second Derivative Test is presented,…

  14. 32 CFR 2001.22 - Derivative classification.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Derivative classification. 2001.22 Section 2001... Identification and Markings § 2001.22 Derivative classification. (a) General. Information classified derivatively on the basis of source documents or classification guides shall bear all markings prescribed...

  15. 40 CFR 721.1820 - Bisphenol derivative.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Bisphenol derivative. 721.1820 Section... Substances § 721.1820 Bisphenol derivative. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as bisphenol derivative (PMN No. P-92-509)...

  16. Bioactive Terpenes from Marine-Derived Fungi

    PubMed Central

    Elissawy, Ahmed M.; El-Shazly, Mohamed; Ebada, Sherif S.; Singab, AbdelNasser B.; Proksch, Peter

    2015-01-01

    Marine-derived fungi continue to be a prolific source of secondary metabolites showing diverse bioactivities. Terpenoids from marine-derived fungi exhibit wide structural diversity including numerous compounds with pronounced biological activities. In this review, we survey the last five years’ reports on terpenoidal metabolites from marine-derived fungi with particular attention on those showing marked biological activities. PMID:25854644

  17. Partial Derivatives of the Lambert Problem

    NASA Technical Reports Server (NTRS)

    Arora, Nitin; Russell, Ryan P.; Strange, Nathan

    2014-01-01

    A procedure for deriving analytic partial derivatives of the Lambert problem is presented. Using the universal, cosine based Lambert formulation; first order partial derivatives of the velocities with respect to the positions and times are developed. Taking advantage of inherent symmetries and intermediate variables, the derivatives are expressed in a computationally efficient form. The added cost of computing these partials is found to be approximately 10% to approximately 60% of the Lambert compute cost. The availability of analytic partial derivatives increases optimization speed, efficiency and allows for trajectory optimization formulations that implicitly enforce continuity constraints via embedded Lambert problems.

  18. Acute overdosage with benzodiazepine derivatives.

    PubMed

    Greenblatt, D J; Allen, M D; Noel, B J; Shader, R I

    1977-04-01

    A total of 773 admissions to Massachusetts General Hospital between 1962 and 1975 were due to acute overdosage with one or more psychotropic drugs. Benzodiazepine overdosage, particularly with diazepam, increased relative to other psychotropic drugs over the years. Only 12 admissions were due to benzodiazepine overdosage alone, and none of these patients were seriously ill or had significant complications. Multiple drugs were ingested in the other 87 cases, and the frequency and severity of complications among these individuals depended upon the type and quantity of other nonbenzodiazepines taken. For example, 21 of 31 patients who ingested benzodiazepines together with barbiturates experienced severe central nervous system (CNS) depression, and 14 of 31 required assisted ventilation. However, the frequency of such complications was nearly identical in a group of patients who ingested barbiturates alone. This report and a review of the literature suggest that serious intoxication following overdosage with a benzodiazepine derivative alone is unusual. Ingestion of benzodiazepines together with other drugs appears to be considerably more common than benzodiazepine overdosage alone as a cause of intoxication. The severity of intoxication in such cases of multiple drug ingestion probably depends largely on the type and quantity of nonbenzodiazepines. PMID:14802

  19. Space-Derived Sewer Monitor

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The QuadraScan Longterm Flow Monitoring System is a second generation sewer monitor developed by American Digital Systems, Inc.'s founder Peter Petroff. Petroff, a former spacecraft instrumentation designer at Marshall Space Flight Center, used expertise based on principles acquired in Apollo and other NASA programs. QuadraScan borrows even more heavily from space technology, for example in its data acquisition and memory system derived from NASA satellites. "One-time" measurements are often plagued with substantial errors due to the flow of groundwater absorbed into the system. These system sizing errors stem from a basic informational deficiency: accurate, reliable data on how much water flows through a sewer system over a long period of time is very difficult to obtain. City officials are turning to "permanent," or long-term sewer monitoring systems. QuadraScan offers many advantages to city officials such as the early warning capability to effectively plan for city growth in order to avoid the crippling economic impact of bans on new sewer connections in effect in many cities today.

  20. STS Derived Exploration Launch Operations

    NASA Technical Reports Server (NTRS)

    Best, Joel; Sorge, L.; Siders, J.; Sias, Dave

    2004-01-01

    A key aspect of the new space exploration programs will be the approach to optimize launch operations. A STS Derived Launch Vehicle (SDLV) Program can provide a cost effective, low risk, and logical step to launch all of the elements of the exploration program. Many benefits can be gained by utilizing the synergy of a common launch site as an exploration spaceport as well as evolving the resources of the current Space Shuttle Program (SSP) to meet the challenges of the Vision for Space Exploration. In particular, the launch operation resources of the SSP can be transitioned to the exploration program and combined with the operations efficiencies of unmanned EELVs to obtain the best of both worlds, resulting in lean launch operations for crew and cargo missions of the exploration program. The SDLV Program would then not only capture the extensive human space flight launch operations knowledge, but also provide for the safe fly-out of the SSP through continuity of system critical skills, manufacturing infrastructure, and ability to maintain and attract critical skill personnel. Thus, a SDLV Program can smoothly transition resources from the SSP and meet the transportation needs to continue the voyage of discovery of the space exploration program.

  1. Unconventional fuel: Tire derived fuel

    SciTech Connect

    Hope, M.W.

    1995-09-01

    Material recovery of scrap tires for their fuel value has moved from a pioneering concept in the early 1980`s to a proven and continuous use in the United States` pulp and paper, utility, industrial, and cement industry. Pulp and paper`s use of tire derived fuel (TDF) is currently consuming tires at the rate of 35 million passenger tire equivalents (PTEs) per year. Twenty mills are known to be burning TDF on a continuous basis. The utility industry is currently consuming tires at the rate of 48 million PTEs per year. Thirteen utilities are known to be burning TDF on a continuous basis. The cement industry is currently consuming tires at the rate of 28 million PTEs per year. Twenty two cement plants are known to be burning TDF on a continuous basis. Other industrial boilers are currently consuming tires at the rate of 6.5 million PTEs per year. Four industrial boilers are known to be burning TDF on a continuous basis. In total, 59 facilities are currently burning over 117 million PTEs per year. Although 93% of these facilities were not engineered to burn TDF, it has become clear that TDF has found acceptance as a supplemental fuel when blending with conventional fuels in existing combustion devices designed for normal operating conditions. The issues of TDF as a supplemental fuel and its proper specifications are critical to the successful development of this fuel alternative. This paper will focus primarily on TDF`s use in a boiler type unit.

  2. Clinical status of benzoporphyrin derivative

    NASA Astrophysics Data System (ADS)

    Levy, Julia G.; Chan, Agnes H.; Strong, H. Andrew

    1996-01-01

    Benzoporphyrin derivative monoacid ring A (BPD) is currently in Phase II clinical trials for the treatment of cutaneous malignancies (basal cell carcinoma and cutaneous metastases) and psoriasis. Results to date suggest that this photosensitizer has potential in both of these areas. Recently, a clinical trial with BPD was initiated for the treatment of age related macular degeneration, a neovascular condition in the eye which leads to blindness. BPD is a lipophilic photosensitizer which is rapidly taken up by activated cells and the vascular endothelium of neovasculature. The PDT effects seen with BPD appear to be a combination of vascular occlusion and direct killing of target cells. Since many diseases involve either activated cells and/or neovasculature, PDT with photosensitizer with characteristics like those of BPD, has applications far wider than oncology. A new area of interest involving photosensitizers is that of immune modulation. A number of photosensitizers have been shown to effect immune modulation in animal models of immune dysfunction including autoimmunity (rheumatoid arthritis, lupus), cutaneous hypersensitivity and allografts. BPD and PHOTOFRINR have both been shown to be effective in ameliorating arthritic symptoms in a number of animal models. The mechanisms by which immune modulation is affected in these studies still remains to be resolved.

  3. Eburnamine derivatives and the brain.

    PubMed

    Vas, Adám; Gulyás, Balázs

    2005-11-01

    The Apocynaceae plant family contains a great number of so called eburnamine-vincamine alkaloids. Quite a few of these alkaloids exert varied pharmacological activities on the cell multiplication, cardiovascular system, and brain functions. Many derivatives were also synthesized to find pharmacologically active compounds better characterized and safer to be administered than the natural plant alkaloids themselves. We concentrate on the eburnamine structures with cerebral activities in this review. Vincamine, vinburnine, vindeburnol, apovincaminate, and vinpocetine (cis-ethyl-apovincaminate) all share modulatory effects on brain circulation and neuronal homeostasis, bear antihypoxic and neuroprotective potencies to various degrees. The most eminent compound of this class of alkaloids is vinpocetine. Since its introduction to the market as a neuroprotective agent many non clinical and clinical studies proved vinpocetine's effects on calmodulin dependent phosphodiesterase E1, on sodium, calcium channels, peripheral benzodiazepine receptor, and glutamate receptors as well as its clinical usefulness in the treatment of post-ischaemic stroke disease states and various disorders of cerebrovascular origin. Lately, positron emission tomography studies proved that vinpocetine has a rapid uptake in the primate and human brain with a heterogeneous distribution pattern (preference areas: thalamus, basal ganglia, and visual cortex) both after intravenous and oral administration. Vinpocetine exerts beneficial effects in cerebral glucose metabolism and regional cerebral blood flow in chronic post-stroke patients. PMID:16158388

  4. Satellite-Derived Management Zones

    NASA Technical Reports Server (NTRS)

    Lepoutre, Damien; Layrol, Laurent

    2005-01-01

    The term "satellite-derived management zones" (SAMZ) denotes agricultural management zones that are subdivisions of large fields and that are derived from images of the fields acquired by instruments aboard Earth-orbiting satellites during approximately the past 15 years. "SAMZ" also denotes the methodology and the software that implements the methodology for creating such zones. The SAMZ approach is one of several products of continuing efforts to realize a concept of precision agriculture, which involves optimal variations in seeding, in application of chemicals, and in irrigation, plus decisions to farm or not to farm certain portions of fields, all in an effort to maximize profitability in view of spatial and temporal variations in the growth and health of crops, and in the chemical and physical conditions of soils. As used here, "management zone" signifies, more precisely, a subdivision of a field within which the crop-production behavior is regarded as homogeneous. From the perspective of precision agriculture, management zones are the smallest subdivisions between which the seeding, application of chemicals, and other management parameters are to be varied. In the SAMZ approach, the main sources of data are the archives of satellite imagery that have been collected over the years for diverse purposes. One of the main advantages afforded by the SAMZ approach is that the data in these archives can be reused for purposes of precision agriculture at low cost. De facto, these archives contain information on all sources of variability within a field, including weather, crop types, crop management, soil types, and water drainage patterns. The SAMZ methodology involves the establishment of a Web-based interface based on an algorithm that generates management zones automatically and quickly from archival satellite image data in response to requests from farmers. A farmer can make a request by either uploading data describing a field boundary to the Web site or else

  5. Longipinane derivatives from Stevia connata.

    PubMed

    Sánchez-Arreola, E; Cerda-García-Rojas, C M; Román, L U; Hernández, J D; Joseph-Nathan, P

    2000-01-01

    The hexane extracts of the roots of Stevia connata afforded three new longipinene derivatives, longipinane-7beta,8alpha, 9alpha-triol-1-one 7-angelate-8-methylbutyrate (1), longipin-2-ene-7beta,8alpha,9alpha-triol-1-one 8,9-diangelate (6), and longipin-2-ene-7beta,8alpha,9alpha-triol-1-one 8-angelate-9-methylbutyrate (8), together with the known longipinane-7beta,8alpha,9alpha-triol-1-one 8,9-diangelate (2), longipinane-7beta,8alpha,9alpha-triol-1-one 7,9-diangelate (3), longipinane-7beta,8alpha,9alpha-triol-1-one 7,8-diangelate (4), longipin-2-ene-7beta,8alpha,9alpha-triol-1-one 7,8-diangelate (5), longipin-2-ene-7beta,8alpha,9alpha-triol-1-one 7-angelate-8-methylbutyrate (12), and stigmasterol. The structures of the new compounds were determined by chemical transformations and spectral methods including 2D NMR measurements. Spontaneous intramolecular transesterifications starting from the 8-angelate-9-methylbutyrate 8 provided an equilibrated mixture of the 7-angelate-9-methylbutyrate 10, the 7-angelate-8-methylbutyrate 12 and the starting material when stored in MeOH-H(2)O solution, while the 8,9-diangelate 6 only provided a binary mixture of the 7, 9-diangelate 7 and the starting material under the same conditions. The structures of 6-8, 10, and 12 and those of the nonisolable reaction intermediates 9, 11, and 14 were further evaluated by AM1 semiempirical calculations. PMID:10650070

  6. Drug laws and the 'derivative' problem.

    PubMed

    King, Leslie A; Ujváry, István; Brandt, Simon D

    2014-01-01

    The concept of a 'derivative' is used widely in chemistry, where its precise meaning depends on the circumstances. However, numerous examples of derivative also occur in domestic drugs legislation, some of which stem from the 1961 United Nations Single Convention on Narcotic Drugs. There is a commonly held view that only 'first-order' derivatives should be considered: substances that can be created from a parent structure in a single chemical reaction. In other words, 'derivatives of derivatives' are excluded. However, some substances related to ecgonine (e.g. 2-carbomethoxytropinone) are clearly convertible to cocaine, even though this may require more than one reaction step. It follows that 2-carbomethoxytropinone is a controlled drug, a situation that most chemists would regard as perverse. A more extreme example of the complexity of 'derivative' is shown by the conversion of thebaine to buprenorphine. Even though this requires six or more stages, the US Drug Enforcement Administration successfully argued in a 1986 case that for the purposes of the Controlled Substances Act, the number of steps required was irrelevant; buprenorphine was a derivative of thebaine. Because the term derivative is rarely defined in statutes, the legal status of some substances, such as 2-bromo-LSD, is uncertain. Although a number of definitions of derivative can be found in the chemical literature, no single definition is adequate to describe all situations where it occurs in legislation. Unless qualified, it is suggested that the term derivative should be avoided in any future legislation. PMID:23949903

  7. Drug Nanoparticle Formulation Using Ascorbic Acid Derivatives

    PubMed Central

    Moribe, Kunikazu; Limwikrant, Waree; Higashi, Kenjirou; Yamamoto, Keiji

    2011-01-01

    Drug nanoparticle formulation using ascorbic acid derivatives and its therapeutic uses have recently been introduced. Hydrophilic ascorbic acid derivatives such as ascorbyl glycoside have been used not only as antioxidants but also as food and pharmaceutical excipients. In addition to drug solubilization, drug nanoparticle formation was observed using ascorbyl glycoside. Hydrophobic ascorbic acid derivatives such as ascorbyl mono- and di-n-alkyl fatty acid derivatives are used either as drugs or carrier components. Ascorbyl n-alkyl fatty acid derivatives have been formulated as antioxidants or anticancer drugs for nanoparticle formulations such as micelles, microemulsions, and liposomes. ASC-P vesicles called aspasomes are submicron-sized particles that can encapsulate hydrophilic drugs. Several transdermal and injectable formulations of ascorbyl n-alkyl fatty acid derivatives were used, including ascorbyl palmitate. PMID:21603195

  8. Anisotropic higher derivative gravity and inflationary universe

    SciTech Connect

    Kao, W. F.

    2006-08-15

    Stability analysis of the Kantowski-Sachs type universe in pure higher derivative gravity theory is studied in detail. The nonredundant generalized Friedmann equation of the system is derived by introducing a reduced one-dimensional generalized Kantowski-Sachs type action. Existence and stability of inflationary solution in the presence of higher derivative terms are also studied in detail. Implications to the choice of physical theories are discussed in detail in this paper.

  9. Transportation Planning with Immune System Derived Approach

    NASA Astrophysics Data System (ADS)

    Sugiyama, Kenji; Yaji, Yasuhito; Ootsuki, John Takuya; Fujimoto, Yasutaka; Sekiguchi, Takashi

    This paper presents an immune system derived approach for planning transportation of materials between manufacturing processes in the factory. Transportation operations are modeled by Petri Net, and divided into submodels. Transportation orders are derived from the firing sequences of those submodels through convergence calculation by the immune system derived excitation and suppression operations. Basic evaluation of this approach is conducted by simulation-based investigation.

  10. Variational Lie derivative and cohomology classes

    NASA Astrophysics Data System (ADS)

    Palese, Marcella; Winterroth, Ekkehart

    2011-07-01

    We relate cohomology defined by a system of local Lagrangian with the cohomology class of the system of local variational Lie derivative, which is in turn a local variational problem; we show that the latter cohomology class is zero, since the variational Lie derivative `trivializes' cohomology classes defined by variational forms. As a consequence, conservation laws associated with symmetries of the second variational derivative of a local variational problem are globally defined.

  11. Generalized gravitational entropy from total derivative action

    NASA Astrophysics Data System (ADS)

    Dong, Xi; Miao, Rong-Xin

    2015-12-01

    We investigate the generalized gravitational entropy from total derivative terms in the gravitational action. Following the method of Lewkowycz and Maldacena, we find that the generalized gravitational entropy from total derivatives vanishes. We compare our results with the work of Astaneh, Patrushev, and Solodukhin. We find that if total derivatives produced nonzero entropy, the holographic and the field-theoretic universal terms of entanglement entropy would not match. Furthermore, the second law of thermodynamics could be violated if the entropy of total derivatives did not vanish.

  12. Mantle derived economic sulfide mineralization?

    NASA Astrophysics Data System (ADS)

    Krivolutskaya, Nadezda; Gongalskiy, Bronislav; Svirskaya, Natalia

    2014-05-01

    Sulfide ores of the unique Pt-Cu-Ni Noril'sk deposits are characterized by heavy sulfur isotopic composition (d34S = 6-18 ‰ ; Grinenko, 1985). These data are traditionally explained by the crustal contamination of the mantle melts by Devonian sedimentary rocks with anhydrites at certain depths or in a chamber of crystallization (Naldrett, 1992; Li et al., 2009). However, data on the distribution of major and trace elements and isotopic composition (their eNd, 87Sr/86Sr, d34S) in the contact zones of the intrusions with the host rocks are at variance with any significant in-situ contamination. Moreover , the mechanism of the "digestion" of this high-temperature material (Tm = 1430ºC) by the lower temperature magma (1250ºC) has never been analyzed and questioned. Our pioneering data on the sulfur radiogenic isotopes in the anhydrite are in conflict with the hypothesis that this mineral could serve as a sulfur source for the Noril'sk ores. The fact that the average composition of the intrusions is independent on the stratigraphic setting of these intrusions, which can be hosted by limestone, sandstone, and/or basalt, provides further support for the idea that no assimilation took place at the depths of the chambers in which the melts crystallized.The reason for the heavy sulfur isotopic composition of ores in the Noril'sk district is still uncertain. Last data obtained on the sulfur isotopic composition of basalts and ores from some intrusions in the Taimyr Peninsula likely provide a clue to this problem. The highest d34S values in rocks of all of the trap formations were detected in the Gudchikhinsky picrites (d34S = +8,7; Ripley et al., 2003) formed from a primitive mantle magma. They are geochemically similar to the rocks from the Dyumtaleysky Massif (d34S = 12.2; Krivolutskaya and Gongalsky, 2013) which crystallized from a primitive mantle-derived magma (with no Ta-Nb and Pb anomalies and high Gd/Yb ratio) too. This intrusion comprises economic important

  13. 17 CFR 200.507 - Declassification dates on derivative documents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... documents. (a) A document that derives its classification from information classified under Executive Order... derivative document that derives its classification from the approved use of the classification guide...

  14. 17 CFR 200.507 - Declassification dates on derivative documents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... documents. (a) A document that derives its classification from information classified under Executive Order... derivative document that derives its classification from the approved use of the classification guide...

  15. 17 CFR 200.507 - Declassification dates on derivative documents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... documents. (a) A document that derives its classification from information classified under Executive Order... derivative document that derives its classification from the approved use of the classification guide...

  16. Inflation with non-minimally derivative coupling

    NASA Astrophysics Data System (ADS)

    Yang, Nan; Gao, Qing; Gong, Yungui

    2015-10-01

    We derive the second order correction to the scalar and tensor spectral tilts for the inflationary models with non-minimally derivative coupling. In the high friction limit, the quartic power law potential is consistent with the observational constraint at 95% CL because the amplitude of the primordial gravitational waves is smaller, and the inflaton excursion is sub-Planckian.

  17. Tilt/Integral/Derivative Compensators For Controllers

    NASA Technical Reports Server (NTRS)

    Lurie, Boris J.

    1995-01-01

    Tilt/integral/derivative (TID) compensators for tunable feedback control systems offer advantages over proportional/integral/derivative compensators. Designed and adjusted more easily, and made to reject disturbances more strongly and less sensitive to variations in parameters of controlled system.

  18. 45 CFR 601.5 - Derivative classification.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 3 2010-10-01 2010-10-01 false Derivative classification. 601.5 Section 601.5 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION..., or who only apply classification markings derived from source material or as directed by...

  19. 12 CFR 403.4 - Derivative classification.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 4 2010-01-01 2010-01-01 false Derivative classification. 403.4 Section 403.4 Banks and Banking EXPORT-IMPORT BANK OF THE UNITED STATES CLASSIFICATION, DECLASSIFICATION, AND SAFEGUARDING OF NATIONAL SECURITY INFORMATION § 403.4 Derivative classification. (a) Use of...

  20. 28 CFR 17.26 - Derivative classification.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., the ISOO implementing directives in 32 CFR 2001.22, and internal Department directions provided by the... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Derivative classification. 17.26 Section... ACCESS TO CLASSIFIED INFORMATION Classified Information § 17.26 Derivative classification. (a)...

  1. 17 CFR 200.506 - Derivative classification.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Derivative classification. 200...; CONDUCT AND ETHICS; AND INFORMATION AND REQUESTS Classification and Declassification of National Security Information and Material § 200.506 Derivative classification. Any document that includes...

  2. 5 CFR 2500.5 - Derivative classification.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 3 2012-01-01 2012-01-01 false Derivative classification. 2500.5 Section 2500.5 Administrative Personnel OFFICE OF ADMINISTRATION, EXECUTIVE OFFICE OF THE PRESIDENT INFORMATION SECURITY REGULATION § 2500.5 Derivative classification. The Office of Administration serves only as...

  3. 5 CFR 2500.5 - Derivative classification.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 3 2011-01-01 2011-01-01 false Derivative classification. 2500.5 Section 2500.5 Administrative Personnel OFFICE OF ADMINISTRATION, EXECUTIVE OFFICE OF THE PRESIDENT INFORMATION SECURITY REGULATION § 2500.5 Derivative classification. The Office of Administration serves only as...

  4. 5 CFR 2500.5 - Derivative classification.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 3 2013-01-01 2013-01-01 false Derivative classification. 2500.5 Section 2500.5 Administrative Personnel OFFICE OF ADMINISTRATION, EXECUTIVE OFFICE OF THE PRESIDENT INFORMATION SECURITY REGULATION § 2500.5 Derivative classification. The Office of Administration serves only as...

  5. 5 CFR 2500.5 - Derivative classification.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 3 2014-01-01 2014-01-01 false Derivative classification. 2500.5 Section 2500.5 Administrative Personnel OFFICE OF ADMINISTRATION, EXECUTIVE OFFICE OF THE PRESIDENT INFORMATION SECURITY REGULATION § 2500.5 Derivative classification. The Office of Administration serves only as...

  6. Analysis of Blackbody Radiation with Derivative Spectroscopy.

    ERIC Educational Resources Information Center

    Dusek, J.; And Others

    1980-01-01

    Describes an undergraduate experiment which uses derivative spectroscopy to investigate the validity of the Planck function appearing in the blackbody radiation law. These measurements allow a critical examination of this function and also serve as an introduction to derivative spectroscopy techniques. (Author/HM)

  7. Understanding the Derivative through the Calculus Triangle

    ERIC Educational Resources Information Center

    Weber, Eric; Tallman, Michael; Byerley, Cameron; Thompson, Patrick W.

    2012-01-01

    Typical treatments of the derivative do not clearly convey the idea that the derivative function represents the original function's rate of change. Revealing the relationship between a function and its rate-of-change function for static values of "x" does not facilitate productive ways of thinking about generating the rate-of-change function or…

  8. 12 CFR 563.172 - Financial derivatives.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Interest Rate Risk, Investment Securities, and Derivatives Activities,” and other applicable agency... chapter), and other applicable agency guidance on implementing a sound risk management program. (e) What..., forward commitments, options, and swaps. A mortgage derivative security, such as a collateralized...

  9. Integrating weather derivatives for managing risks

    SciTech Connect

    Bilski, B.

    1999-11-01

    As deregulation and customer choice loom on the horizon, many energy utilities and other energy suppliers are scrambling to find new services that add value for consumers. Many are also seeking opportunities for increasing efficiency to ensure that costs remain competitive. Integrating weather derivatives with marketing programs and financial management can produce attractive new services and increase efficiency. Weather derivatives can be used to create innovative consumer services, such as a guaranteed annual energy bill which is unaffected by weather and energy price changes. They can also be used to protect the earnings of energy suppliers from one of their most significant financial risks, unpredictable weather. There are three basic types of weather derivatives available today. Option or insurance based derivatives (options), swaps or hedge based derivatives (swaps) and packages where other services are combined with one or both of the above.

  10. Eulerian derivation of the Coriolis force

    NASA Astrophysics Data System (ADS)

    Kageyama, Akira; Hyodo, Mamoru

    2006-02-01

    In textbooks of geophysical fluid dynamics, the Coriolis force and the centrifugal force in a rotating fluid system are derived by making use of the fluid parcel concept. In contrast to this intuitive derivation to the apparent forces, more rigorous derivation would be useful not only for the pedagogical purpose but also for the applications to other kinds of rotating geophysical systems rather than the fluid. The purpose of this paper is to show a general procedure to derive the transformed equations in the rotating frame of reference based on the local Galilean transformation and rotational coordinate transformation of field quantities. The generality and usefulness of this Eulerian approach is demonstrated in the derivation of apparent forces in rotating fluids as well as the transformed electromagnetic field equation in the rotating system.

  11. Risk management, derivatives and shariah compliance

    NASA Astrophysics Data System (ADS)

    Bacha, Obiyathulla Ismath

    2013-04-01

    Despite the impressive growth of Islamic Banking and Finance (IBF), a number of weaknesses remain. The most important of this is perhaps the lack of shariah compliant risk management tools. While the risk sharing philosophy of Islamic Finance requires the acceptance of risk to justify returns, the shariah also requires adherents to avoid unnecessary risk-maysir. The requirement to avoid maysir is in essence a call for the prudent management of risk. Contemporary risk management revolves around financial engineering, the building blocks of which are financial derivatives. Despite the proven efficacy of derivatives in the management of risk in the conventional space, shariah scholars appear to be suspicious and uneasy with their use in IBF. Some have imposed outright prohibition of their use. This paper re-examines the issue of contemporary derivative instruments and shariah compliance. The shariah compatibility of derivatives is shown in a number of ways. First, by way of qualitative evaluation of whether derivatives can be made to comply with the key prohibitions of the sharia. Second, by way of comparing the payoff profiles of derivatives with risk sharing finance and Bai Salam contracts. Finally, the equivalence between shariah compliant derivatives like the IPRS and Islamic FX Currency Forwards with conventional ones is presented.

  12. ADIFOR: Fortran source translation for efficient derivatives

    SciTech Connect

    Bischof, C.; Corliss, G.; Griewank, A.; Hovland, P. ); Carle, A. . Center for Research on Parallel Computation)

    1992-01-01

    The numerical methods employed in the solution of many scientific computing problems require the computation of derivatives of a function f: R{sup n} {yields} R{sup m}. Both the accuracy and the computational requirements of the derivative computation are usually of critical importance for the robustness and speed of the numerical method. ADIFOR (Automatic Differentiation In FORtran) is a source translation tool implemented using the data abstractions and program analysis capabilities of the ParaScope Parallel Programming Environment. ADIFOR accepts arbitrary Fortran-77 code defining the computation of a function and writes portable Fortran-77 code for the computation of its derivatives. In contrast to previous approaches, ADIFOR views automatic differentiation as a process of source translation that exploits computational context to reduce the cost of derivative computations. Experimental results show that ADIFOR can handle real-life codes, providing exact derivatives with a running time that is competitive with the standard divided-difference approximations of derivatives and which may perform orders of magnitude faster than divided-differences in cases. The computational scientist using ADIFOR is freed from worrying about the accurate and efficient computation of derivatives, even for complicated functions,'' and hence, is able to concentrate on the more important issues of algorithm design or system modeling. 35 refs.

  13. Stability-Derivative Determination from Flight Data

    NASA Technical Reports Server (NTRS)

    Holowicz, Chester H.; Holleman, Euclid C.

    1958-01-01

    A comprehensive discussion of the various factors affecting the determination of stability and control derivatives from flight data is presented based on the experience of the NASA High-Speed Flight Station. Factors relating to test techniques, determination of mass characteristics, instrumentation, and methods of analysis are discussed. For most longitudinal-stability-derivative analyses simple equations utilizing period and damping have been found to be as satisfactory as more comprehensive methods. The graphical time-vector method has been the basis of lateral-derivative analysis, although simple approximate methods can be useful If applied with caution. Control effectiveness has been generally obtained by relating the peak acceleration to the rapid control input, and consideration must be given to aerodynamic contributions if reasonable accuracy is to be realized.. Because of the many factors involved In the determination of stability derivatives, It is believed that the primary stability and control derivatives are probably accurate to within 10 to 25 percent, depending upon the specific derivative. Static-stability derivatives at low angle of attack show the greatest accuracy.

  14. Derivation of GFDM Based on OFDM Principles

    SciTech Connect

    Hussein Moradi; Behrouz Farhang-Boroujeny

    2015-06-01

    This paper starts with discussing the principle based on which the celebrated orthogonal frequency division multiplexing (OFDM) signals are constructed. It then extends the same principle to construct the newly introduced generalized frequency division multiplexing (GFDM) signals. This novel derivation sheds light on some interesting properties of GFDM. In particular, our derivation seamlessly leads to an implementation of GFDM transmitter which has significantly lower complexity than what has been reported so far. Our derivation also facilitates a trivial understanding of how GFDM (similar to OFDM) can be applied in MIMO channels.

  15. Four new bibenzyl derivatives from Dendrobium candidum.

    PubMed

    Li, Yan; Wang, Chun-Lan; Wang, Ya-Jun; Wang, Fang-Fei; Guo, Shun-Xing; Yang, Jun-Shan; Xiao, Pei-Gen

    2009-09-01

    Four new bibenzyl derivatives, namely, dendrocandins F-I (1-4), were isolated from the stems of Dendrobium candidum. Their structures were elucidated by the analysis of spectroscopic data. Dendrocandins F and G represent the fourth and fifth example of bisbibenzyl derivates with a dibenzopyran ring between two units, respectively. Dendrocandin H represents the first example of a bibenzyl derivative formed by a bibenzyl and a 1,4-phenanthraquinone unit via a dibenzopyran ring. Compounds 1-4 were examined for antioxidant activity by 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay. PMID:19721264

  16. Theory of Financial Risk and Derivative Pricing

    NASA Astrophysics Data System (ADS)

    Bouchaud, Jean-Philippe; Potters, Marc

    2004-02-01

    Summarizing market data developments, some inspired by statistical physics, this book explains how to better predict the actual behavior of financial markets with respect to asset allocation, derivative pricing and hedging, and risk control. Risk control and derivative pricing are major concerns to financial institutions. The need for adequate statistical tools to measure and anticipate amplitude of potential moves of financial markets is clearly expressed, in particular for derivative markets. Classical theories, however, are based on assumptions leading to systematic (sometimes dramatic) underestimation of risks. First edition Hb (2000): 0-521-78232-5

  17. [Mechanism of Platinum Derivatives Induced Kidney Injury].

    PubMed

    Yan, Feifei; Duan, Jianchun; Wang, Jie

    2015-09-20

    Platinum derivatives are the most widely used chemotherapeutic agents to treat solid tumors including ovarian, head and neck, and testicular germ cell tumors, lung cancer, and colorectal cancer. Two major problems exist, however, in the clinic use of platinum derivatives. One is the development of tumor resistance to the drug during therapy, leading to treatment failure. The other is the drug's toxicity such as the cisplatin's nephrotoxicity, which limits the dose that can be administered. This paper describes the mechanism of platinum derivatives induced kidney injury. PMID:26383983

  18. A new Bisabolane Derivative of Leontopodium andersonii

    PubMed Central

    Schwaiger, Stefan; Hehenberger, Stefanie; Ellmerer, Ernst P.; Stuppner, Hermann

    2012-01-01

    Phytochemical investigations of the roots of Leontopodium andersonii C. B. Clarke (Asteraceae) resulted in the isolation of a new bisabolane sesquiterpene derivative. The structure of the highly substituted derivative (1R*, 5S*, 6S*)-5-(acetyloxy)-6-[3-(acetyloxy)-1,5-dimethylhex-4-enyl]-3-methylcyclohex-2-en-4-on-1-yl (2Z)-2-methyl-but-2-enoate was established by 1- and 2-D-NMR spectroscopy and is the first report of a bisabolone derivative of the genus Leontopodium. PMID:20521527

  19. Synthesis of new polysialic acid derivatives.

    PubMed

    Su, Yi; Kasper, Cornelia; Kirschning, Andreas; Dräger, Gerald; Berski, Silke

    2010-09-01

    In this paper we report the first synthesis of novel polysialic acid derivatives which is initiated by treatment of polysialic acid with EDC-HCl to yield the inter-residual delta-lactone. Subsequent reaction with amines or hydrazine gives the corresponding polysialic acid amides and hydrazide. Alkylation of the tetrabutylammonium salt of polysialic acid yields polysialic acid esters. In contrast a variety of N-derivatives of polysialic acid can be prepared starting from deacetylated polysialic acid. The N-derivatives prepared in this communication can be used for the Cu-catalyzed as well as Cu-free "click" chemistry. PMID:20602419

  20. The Theory of Quaternion Matrix Derivatives

    NASA Astrophysics Data System (ADS)

    Xu, Dongpo; Mandic, Danilo P.

    2015-03-01

    A systematic theory is introduced for calculating the derivatives of quaternion matrix function with respect to quaternion matrix variables. The proposed methodology is equipped with the matrix product rule and chain rule and it is able to handle both analytic and nonanalytic functions. This corrects a flaw in the existing methods, that is, the incorrect use of the traditional product rule. In the framework introduced, the derivatives of quaternion matrix functions can be calculated directly without the differential of this function. Key results are summarized in tables. Several examples show how the quaternion matrix derivatives can be used as an important tool for solving problems related to signal processing.

  1. Casimir Energy Associated With Fractional Derivative Field

    SciTech Connect

    Lim, S. C.

    2007-04-28

    Casimir energy associated with fractional derivative scalar massless field at zero and positive temperature can be obtained using the regularization based on generalized Riemann zeta function of Epstein-Hurwitz type.

  2. Sums and Differences vs. Integrals and Derivatives.

    ERIC Educational Resources Information Center

    Strang, Gilbert

    1990-01-01

    Offers an approach to the understanding and to the teaching of the fundamental theorem of calculus. Stresses teaching the relation between a function and its derivative and the functions themselves. (YP)

  3. SCM Forcing Data Derived from NWP Analyses

    DOE Data Explorer

    Jakob, Christian

    2008-01-15

    Forcing data, suitable for use with single column models (SCMs) and cloud resolving models (CRMs), have been derived from NWP analyses for the ARM (Atmospheric Radiation Measurement) Tropical Western Pacific (TWP) sites of Manus Island and Nauru.

  4. Perspectives on Biologically Active Camptothecin Derivatives

    PubMed Central

    Liu, Ying-Qian; Li, Wen-Qun; Morris-Natschke, Susan L.; Qian, Keduo; Yang, Liu; Zhu, Gao-Xiang; Wu, Xiao-Bing; Chen, An-Liang; Zhang, Shao-Yong; Song, Zi-Long; Lee, Kuo-Hsiung

    2015-01-01

    Camptothecins (CPTs) are cytotoxic natural alkaloids that specifically target DNA topoisomerase I. Research on CPTs has undergone a significant evolution from the initial discovery of CPT in the late 1960s through the study of synthetic small molecule derivatives to investigation of macromolecular constructs and formulations. Over the past years, intensive medicinal chemistry efforts have generated numerous CPT derivatives. Three derivatives, topotecan, irinotecan, and belotecan, are currently prescribed as anticancer drugs, and several related compounds are now in clinical trials. Interest in other biological effects, besides anticancer activity, of CPTs is also growing exponentially, as indicated by the large number of publications on the subject during the last decades. Therefore, the main focus of the present review is to provide an ample but condensed overview on various biological activities of CPT derivatives, in addition to continued up-to-date coverage of anticancer effects. PMID:25808858

  5. Derivatives of the Stochastic Growth Rate

    PubMed Central

    Steinsaltz, David; Tuljapurkar, Shripad; Horvitz, Carol

    2011-01-01

    We consider stochastic matrix models for population driven by random environments which form a Markov chain. The top Lyapunov exponent a, which describes the long-term growth rate, depends smoothly on the demographic parameters (represented as matrix entries) and on the parameters that define the stochastic matrix of the driving Markov chain. The derivatives of a — the “stochastic elasticities” — with respect to changes in the demographic parameters were derived by Tuljapurkar (1990). These results are here extended to a formula for the derivatives with respect to changes in the Markov chain driving the environments. We supplement these formulas with rigorous bounds on computational estimation errors, and with rigorous derivations of both the new and the old formulas. PMID:21463645

  6. A naphthoquinone derivative from Tectona grandis (Linn.).

    PubMed

    Gupta, Pradeep K; Singh, Pahup

    2004-09-01

    A new naphthoquinone derivative has been isolated, along with a number of prenylnaphthoquinone congeners, from the heartwood of Tectona grandis (Linn.). It was characterized as dehydro-alpha-isodunnione (1) by careful analysis of its spectral data. PMID:15224424

  7. MANGROVE-DERIVED NUTRIENTS AND CORAL REEFS

    EPA Science Inventory

    Understanding the consequences of the declining global cover of mangroves due to anthropogenic disturbance necessitates consideration of how mangrove-derived nutrients contribute to threatened coral reef systems. We sampled potential sources of organic matter and a suite of sessi...

  8. 45 CFR 601.5 - Derivative classification.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION... information that is already classified, and marking the newly developed material consistent with the marking..., or who only apply classification markings derived from source material or as directed by...

  9. 45 CFR 601.5 - Derivative classification.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION... information that is already classified, and marking the newly developed material consistent with the marking..., or who only apply classification markings derived from source material or as directed by...

  10. 45 CFR 601.5 - Derivative classification.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION... information that is already classified, and marking the newly developed material consistent with the marking..., or who only apply classification markings derived from source material or as directed by...

  11. 45 CFR 601.5 - Derivative classification.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION... information that is already classified, and marking the newly developed material consistent with the marking..., or who only apply classification markings derived from source material or as directed by...

  12. Patient-Derived Antibody Targets Tumor Cells

    Cancer.gov

    An NCI Cancer Currents blog on an antibody derived from patients that killed tumor cells in cell lines of several cancer types and slowed tumor growth in mouse models of brain and lung cancer without evidence of side effects.

  13. Catalytic combustion of coal-derived liquids

    NASA Technical Reports Server (NTRS)

    Bulzan, D. L.; Tacina, R. R.

    1981-01-01

    A noble metal catalytic reactor was tested with three grades of SRC 2 coal derived liquids, naphtha, middle distillate, and a blend of three parts middle distillate to one part heavy distillate. A petroleum derived number 2 diesel fuel was also tested to provide a direct comparison. The catalytic reactor was tested at inlet temperatures from 600 to 800 K, reference velocities from 10 to 20 m/s, lean fuel air ratios, and a pressure of 3 x 10 to the 5th power Pa. Compared to the diesel, the naphtha gave slightly better combustion efficiency, the middle distillate was almost identical, and the middle heavy blend was slightly poorer. The coal derived liquid fuels contained from 0.58 to 0.95 percent nitrogen by weight. Conversion of fuel nitrogen to NOx was approximately 75 percent for all three grades of the coal derived liquids.

  14. Plant-derived nanostructures: types and applications

    EPA Science Inventory

    Plant-derived nanostructures and nanoparticles (NPs) have functional applications in numerous disciplines such as health care, food and feed, cosmetics, biomedical science, energy science, drug-gene delivery, environmental health, and so on. Consequently, it is imperative for res...

  15. Frequency analysis of photoplethysmogram and its derivatives.

    PubMed

    Elgendi, Mohamed; Fletcher, Richard R; Norton, Ian; Brearley, Matt; Abbott, Derek; Lovell, Nigel H; Schuurmans, Dale

    2015-12-01

    There are a limited number of studies on heat stress dynamics during exercise using the photoplethysmogram (PPG). We investigate the PPG signal and its derivatives for heat stress assessment using Welch (non-parametric) and autoregressive (parametric) spectral estimation methods. The preliminary results of this study indicate that applying the first and second derivatives to PPG waveforms is useful for determining heat stress level using 20-s recordings. Interestingly, Welch's and Yule-Walker's methods in agreement that the second derivative is an improved detector for heat stress. In fact, both spectral estimation methods showed a clear separation in the frequency domain between measurements before and after simulated heat-stress induction when the second derivative is applied. Moreover, the results demonstrate superior performance of the Welch's method over the Yule-Walker's method in separating before and after the three simulated heat-stress inductions. PMID:26498064

  16. Drilling fluid containing crosslinked polysaccharide derivative

    SciTech Connect

    Demott, D.N.; Kucera, C.H.

    1981-03-24

    A drilling fluid having extremely desirable physical properties which comprises an aqueous solution of a hydroxyalkyl polysaccharide derivative and a water soluble ionic aluminum crosslinking agent, preferably sodium aluminate.

  17. Analysis and the Derivation of Valid Objectives

    ERIC Educational Resources Information Center

    Tiemann, Philip W.

    1973-01-01

    Author states that "to the extent that behavioral objectives are derived from an analysis of relatively broad objectives, they can serve as valid criteria which enable our students to avoid trivia." (Author)

  18. 28 CFR 17.26 - Derivative classification.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., the ISOO implementing directives in 32 CFR 2001.22, and internal Department directions provided by the... need not possess original classification authority to derivatively classify information based on...

  19. Entanglement entropy in higher derivative holography

    NASA Astrophysics Data System (ADS)

    Bhattacharyya, Arpan; Kaviraj, Apratim; Sinha, Aninda

    2013-08-01

    We consider holographic entanglement entropy in higher derivative gravity theories. Recently Lewkowycz and Maldacena [1] have provided a method to derive the equations for the entangling surface from first principles. We use this method to compute the entangling surface in four derivative gravity. Certain interesting differences compared to the two derivative case are pointed out. For Gauss-Bonnet gravity, we show that in the regime where this method is applicable, the resulting equations coincide with proposals in the literature as well as with what follows from considerations of the stress tensor on the entangling surface. Finally we demonstrate that the area functional in Gauss-Bonnet holography arises as a counterterm needed to make the Euclidean action free of power law divergences.

  20. Polyimides Derived from Novel Asymmetric Benzophenone Dianhydrides

    NASA Technical Reports Server (NTRS)

    Chuang, Chun-Hua (Inventor)

    2015-01-01

    This invention relates to the composition and processes for preparing thermoset polyimides derived from an asymmetric dianhydride, namely 2,3,3',4'-benzophenone dianhydride (a-BTDA) with at least one diamine, and a monofunctional terminal endcaps. The monofunctional terminating groups include 4-phenylethynylphthalic anhydride ester-acid derivatives, phenylethyl trimellitic anhydride (PETA) and its ester derivatives as well as 3-phenylethynylaniline. The process of polyimide composite comprises impregnating monomer reactants of dianhydride or its ester-acid derivatives, diamine and with monofunctional reactive endcaps into glass, carbon, quartz or synthetic fibers and fabrics, and then stack up into laminates and subsequently heated to between 150-375.degree. C. either at atmosphere or under pressure to promote the curing and crosslinking of the reactive endcaps to form a network of thermoset polyimides.

  1. Development of thermally stable phosphonitrile elastomers for advanced aerospace structures

    NASA Technical Reports Server (NTRS)

    Reynard, K. A.; Gerber, A. H.; Peterson, T.; Rose, S. H.

    1973-01-01

    Both high and low molecular weight, curable poly(fluoroalkoxy phosphazene) terpolymers were prepared. These terpolymers resulted from reaction of (Cl2PNn) polymer with alkoxides derived from CF3CH2OH and C3F7CH2OH, and an alkoxide derived from CH3CH(OH)C2H4OH. The terpolymers were crosslinked with polyisocyanates at room temperature. High molecular weight materials were converted into isocyanate prepolymers which as films underwent moisture cures at room temperature. Prepolymer solutions were stable for several days, and showed good adhesion. Also the effects of polymerization of (Cl2PN)3 were studied. Purified octachlorophosphazene, thiocyanate salts, or hydrogen chloride were employed in attempts to decrease molecular weight. Hydrogen chloride was found to be a good agent for preparation of low molecular weight poly(dichloro phosphazene).

  2. Analytical second derivatives for effective core potentials

    NASA Astrophysics Data System (ADS)

    Breidung, Jürgen; Thiel, Walter; Komornicki, Andrew

    1988-12-01

    Analytical first and second derivatives for effective core potentials are reported. The computational implementation of the derivative formulas makes use of new integral routines which take advantage of the shell concept. Test calculations for H 3SnBr and F 3AsS demonstrate the efficiency of the analytical determination of harmonic force fields using effective core potentials. The spectroscopic constants of the unknown molecule F 3AsS are predicted.

  3. Computer derivation of some dolphin echolocation signals.

    PubMed

    Altes, R A

    1971-09-01

    Recent advances in radar theory have given rise to a straightforward method of sonar signal design. The method involves computer maximization of a signal-to-interference ratio. The procedure has been used to derive sonar signals that can accurately measure target velocity. When two dolphins were placed in a situation conducive to the utilization of such signals, their waveforms were similar to those that had been theoretically derived. PMID:17751313

  4. On computing Laplace's coefficients and their derivatives.

    NASA Astrophysics Data System (ADS)

    Gerasimov, I. A.; Vinnikov, E. L.

    The algorithm of computing Laplace's coefficients and their derivatives is proposed with application of recurrent relations. The A.G.M.-method is used for the calculation of values L0(0), L0(1). The FORTRAN-program corresponding to the algorithm is given. The precision control was provided with numerical integrating by Simpsons method. The behavior of Laplace's coefficients and their third derivatives whith varying indices K, n for fixed values of the α-parameter is presented graphically.

  5. Analytic computation of energy derivatives - Relationships among partial derivatives of a variationally determined function

    NASA Technical Reports Server (NTRS)

    King, H. F.; Komornicki, A.

    1986-01-01

    Formulas are presented relating Taylor series expansion coefficients of three functions of several variables, the energy of the trial wave function (W), the energy computed using the optimized variational wave function (E), and the response function (lambda), under certain conditions. Partial derivatives of lambda are obtained through solution of a recursive system of linear equations, and solution through order n yields derivatives of E through order 2n + 1, extending Puley's application of Wigner's 2n + 1 rule to partial derivatives in couple perturbation theory. An examination of numerical accuracy shows that the usual two-term second derivative formula is less stable than an alternative four-term formula, and that previous claims that energy derivatives are stationary properties of the wave function are fallacious. The results have application to quantum theoretical methods for the computation of derivative properties such as infrared frequencies and intensities.

  6. New steroid derivative with hypoglycemic activity

    PubMed Central

    Lauro, Figueroa-Valverde; Francisco, Díaz-Cedillo; Lenin, Hau-Heredia; Elodia, García-Cervera; Eduardo, Pool-Gómez; Marcela, Rosas-Nexticapa; Bety, Sarabia-Alcocer

    2014-01-01

    Data indicates that some steroid derivatives may induce changes on glucose levels; nevertheless, data are very confusing. Therefore, more pharmacological data are needed to characterize the activity induced by the steroid derivatives on glucose levels. The aim of this study was to synthesize a new steroid derivative for evaluate its hypoglycemic activity. The effects of steroid derivative on glucose concentration were evaluated in a diabetic animal model using glibenclamide and metformin as controls. In addition, the pregnenolone-dihydrotestosterone conjugate was bound to Tc-99m using radioimmunoassay methods, to evaluate the pharmacokinetics of the steroid derivative over time. The results showed that the pregnenolone-dihydrotestosterone conjugate induces changes on the glucose levels in similar form than glibenclamide. Other data showed that the biodistribution of Tc-99m-steroid derivativein brain was higher in comparison with spleen, stomach, intestine liver and kidney. In conclusion, the pregnenolone-dihydrotestosterone conjugate exerts hypoglycemic activity and this phenomenon could depend of its physicochemical properties which could be related to the degree of lipophilicity of the steroidderivative. PMID:25550906

  7. Microscopically derived free energy of dislocations

    NASA Astrophysics Data System (ADS)

    Kooiman, M.; Hütter, M.; Geers, M. G. D.

    2015-05-01

    The dynamics of large amounts of dislocations is the governing mechanism in metal plasticity. The free energy of a continuous dislocation density profile plays a crucial role in the description of the dynamics of dislocations, as free energy derivatives act as the driving forces of dislocation dynamics. In this contribution, an explicit expression for the free energy of straight and parallel dislocations with different Burgers vectors is derived. The free energy is determined using systematic coarse-graining techniques from statistical mechanics. The starting point of the derivation is the grand-canonical partition function derived in an earlier work, in which we accounted for the finite system size, discrete glide planes and multiple slip systems. In this paper, the explicit free energy functional of the dislocation density is calculated and has, to the best of our knowledge, not been derived before in the present form. The free energy consists of a mean-field elastic contribution and a local defect energy, that can be split into a statistical and a many-body contribution. These depend on the density of positive and negative dislocations on each slip system separately, instead of GND-based quantities only. Consequently, a crystal plasticity model based on the here obtained free energy, should account for both statistically stored and geometrically necessary dislocations.

  8. Inequalities for angular derivatives and boundary interpolation

    NASA Astrophysics Data System (ADS)

    Bolotnikov, Vladimir; Elin, Mark; Shoikhet, David

    2013-03-01

    The classical Julia-Wolff-Carathéodory theorem asserts that the angular derivative of a holomorphic self-mapping of the open unit disk (Schur function) at its boundary fixed point is a positive number. Cowen and Pommerenke (J Lond Math Soc 26:271-289, 1982) proved that if a Schur function has several boundary regular fixed (or mutual contact) points, then the angular derivatives at these points are subject to certain inequalities. We develop a unified approach to establish relations between angular derivatives of Schur functions with a prescribed (possibly, infinite) collection of either mutual contact points or boundary fixed points. This approach yields diverse inequalities improving both classical and more recent results. We apply them to study the Nevanlinna-Pick interpolation problem with boundary data. Our methods lead to fairly explicit formulas describing the set of solutions.

  9. Derivative expansion of the effective action

    SciTech Connect

    Cheyette, O.

    1987-04-01

    This paper describes some methods for calculating derivative terms in the one loop effective action for a quantum field theory. The functional approach and background field method are first used to derive the general form of the one loop determinant. Then the determinant is expanded in powers of derivatives of the background fields. The form of this expansion is described for the simple case of an interacting scalar field, and then for the more complicated problem of a non-abelian gauge field. Finally, the expansion is applied to the task of calculating Higgs mass dependent effects in the Glashow-Weinberg-Salam model, and all terms which grow with the Higgs mass M/sub H/ are found in the one loop approximation. The result of this calculation is used to find the dependence of the gauge boson mass ratio rho on M/sub H/, and also to estimate the size of corrections to W and Z scattering theorems.

  10. Understanding, Deriving, and Computing Buffer Capacity

    NASA Astrophysics Data System (ADS)

    Urbansky, Edward T.; Schock, Michael R.

    2000-12-01

    The concept of buffer capacity appears in varied disciplines, including bio-, geo-, analytical, and environmental chemistry, physiology, medicine, dentistry, and agriculture. Unfortunately, however, derivation and systematic calculation of buffer capacity is a topic that seems to be neglected in the undergraduate analytical chemistry curriculum. In this work, we give an account of the development of the buffer capacity concept and derive the buffer capacity contribution equations for buffer systems containing mono-, di-, and triprotic weak acids (and their conjugate bases) and aluminum(III), which undergoes hydrolysis. A brief review of pH is provided because pH is involved in applying buffer capacity to the real world. In addition, we discuss evaluation of the equations, numerical approximation of buffer capacity when an analytic solution is not derived, and the mathematical properties of the buffer capacity expressions.

  11. Real-time cosmography with redshift derivatives

    NASA Astrophysics Data System (ADS)

    Martins, C. J. A. P.; Martinelli, M.; Calabrese, E.; Ramos, M. P. L. P.

    2016-08-01

    The drift in the redshift of objects passively following the cosmological expansion has long been recognized as a key model-independent probe of cosmology. Here, we study the cosmological relevance of measurements of time or redshift derivatives of this drift, arguing that the combination of first and second redshift derivatives is a powerful test of the Λ CDM cosmological model. In particular, the latter can be obtained numerically from a set of measurements of the drift at different redshifts. We show that, in the low-redshift limit, a measurement of the derivative of the drift can provide a constraint on the jerk parameter, which is j =1 for flat Λ CDM , while generically j ≠1 for other models. We emphasize that such a measurement is well within the reach of the ELT-HIRES and SKA Phase 2 array surveys.

  12. Second derivatives for approximate spin projection methods

    SciTech Connect

    Thompson, Lee M.; Hratchian, Hrant P.

    2015-02-07

    The use of broken-symmetry electronic structure methods is required in order to obtain correct behavior of electronically strained open-shell systems, such as transition states, biradicals, and transition metals. This approach often has issues with spin contamination, which can lead to significant errors in predicted energies, geometries, and properties. Approximate projection schemes are able to correct for spin contamination and can often yield improved results. To fully make use of these methods and to carry out exploration of the potential energy surface, it is desirable to develop an efficient second energy derivative theory. In this paper, we formulate the analytical second derivatives for the Yamaguchi approximate projection scheme, building on recent work that has yielded an efficient implementation of the analytical first derivatives.

  13. Analytics of Quinine and its Derivatives.

    PubMed

    Kluska, Mariusz; Marciniuk-Kluska, Anna; Prukała, Dorota; Prukała, Wiesław

    2016-01-01

    The objective of this study was to perform a synthesis and analysis of the most important information on quinine and its derivatives, which are still very important in the treatment of malaria. The analysis of stereoisomers of quinine and its derivatives was conducted using two techniques, high-performance liquid chromatography and capillary electrophoresis. Particularly noteworthy is the technique used for the determination of isotachophoresis, referred to as one of the so-called green chemistry techniques. Particular attention was paid to properties and the use of quinine and its derivatives in the treatment of malaria. The analytical part will supplement knowledge about quinidine, quinine, and cinchonidine, and will contribute to the growth of research on the so-much-needed drugs against malaria. PMID:25831406

  14. Phase retrieval from one partial derivative.

    PubMed

    Matías Di Martino, J; Flores, Jorge L; Pfeiffer, Franz; Scherer, Kai; Ayubi, Gastón A; Ferrari, José A

    2013-11-15

    Phase objects can be characterized using well-known methods such as shear interferometry and deflectometry, which provide information on the partial derivatives of the phase. It is often believed that for phase retrieval it is strictly necessary to have knowledge of two partial derivatives in orthogonal directions. In the praxis, this implies that the measurements have to be performed along two dimensions, which often requires a rotation of the object or rotation of the shear direction. This is time consuming and errors can be easily generated from the process of rotation, especially for image registration in the axial direction. In the present Letter, we will demonstrate that only one partial derivative often suffices to recover the phase, and we will discuss under which conditions that is possible. Simulations and validation experiments are presented. PMID:24322139

  15. Halogenated coumarin derivatives as novel seed protectants.

    PubMed

    Brooker, N; Windorski, J; Bluml, E

    2008-01-01

    Development of new and improved antifungal compounds that are target-specific is backed by a strong Federal, public and commercial mandate. Many plant-derived chemicals have proven fungicidal properties, including the coumarins (1,2-Benzopyrone) found in a variety of plants such as clover, sweet woodruff and grasses. Preliminary research has shown the coumarins to be a highly active group of molecules with a wide range of antimicrobial activity against both fungi and bacteria. It is believed that these cyclic compounds behave as natural pesticidal defence molecules for plants and they represent a starting point for the exploration of new derivative compounds possessing a range of improved antifungal activity. Within this study, derivatives of coumarin that were modified with halogenated side groups were screened for their antifungal activity against a range of soil-borne plant pathogenic fungi. Fungi included in this in vitro screen included Macrophomina phaseolina (charcoal rot), Phytophthora spp. (damping off and seedling rot), Rhizoctonia spp. (damping off and root rot) and Pythium spp. (seedling blight), four phylogenetically diverse and economically important plant pathogens. Studies indicate that these halogenated coumarin derivatives work very effectively in vitro to inhibit fungal growth and some coumarin derivatives have higher antifungal activity and stability as compared to the original coumarin compound alone. The highly active coumarin derivatives are brominated, iodinated and chlorinated compounds and results suggest that besides being highly active, very small amounts can be used to achieve LD100 rates. In addition to the in vitro fungal inhibition assays, results of polymer seed coating compatibility and phytotoxicity testing using these compounds as seed treatments will also be reported. These results support additional research in this area of natural pesticide development. PMID:19226745

  16. Hydrogermylation of itaconic and sorbic derivatives

    SciTech Connect

    Gar, T.K.; Viktorov, N.A.; Nosova, V.M.; Kisin, A.V.; Ivashchenko, D.A.; Popkov, M.K.; Mironov, V.F.

    1987-10-10

    We have investigated the reactions of trichlorogermane with itaconic acid and its derivatives and also with derivatives of sorbic acid. It was shown that the acid chlorides and the anhydride of itaconic acid readily undergo addition with the trichlorogermane ether complex. The structures of the compounds obtained were determined by means of /sup 1/H and /sup 13/C NMR spectroscopy with the use of model compounds: 3-butenoyl chloride, methyl 3-butenoate, crotonoyl chloride, methyl crotonate, and products of the addition of trichlorogermane ether complex to the latter.

  17. Special Relativity Derived from Spacetime Magma

    PubMed Central

    Greensite, Fred

    2014-01-01

    We present a derivation of relativistic spacetime largely untethered from specific physical considerations, in constrast to the many physically-based derivations that have appeared in the last few decades. The argument proceeds from the inherent magma (groupoid) existing on the union of spacetime frame components and Euclidean which is consistent with an “inversion symmetry” constraint from which the Minkowski norm results. In this context, the latter is also characterized as one member of a class of “inverse norms” which play major roles with respect to various unital -algebras more generally. PMID:24959889

  18. Quantum mechanics of 4-derivative theories

    NASA Astrophysics Data System (ADS)

    Salvio, Alberto; Strumia, Alessandro

    2016-04-01

    A renormalizable theory of gravity is obtained if the dimension-less 4-derivative kinetic term of the graviton, which classically suffers from negative unbounded energy, admits a sensible quantization. We find that a 4-derivative degree of freedom involves a canonical coordinate with unusual time-inversion parity, and that a correspondingly unusual representation must be employed for the relative quantum operator. The resulting theory has positive energy eigenvalues, normalizable wavefunctions, unitary evolution in a negative-norm configuration space. We present a formalism for quantum mechanics with a generic norm.

  19. Synthesis of Amaryllidaceae Constituents and Unnatural Derivatives.

    PubMed

    Ghavre, Mukund; Froese, Jordan; Pour, Milan; Hudlicky, Tomas

    2016-05-01

    This update covers the syntheses of Amaryllidaceae alkaloids since the publication of the last major review in 2008. A short summary of past syntheses and their step count is provided for the major constituents; pancratistatin, 7-deoxypancratistatin, narciclasine, lycoricidine, lycorine, and for other natural constituents, as well as for unnatural derivatives. Discussion of biological activities is provided for unnatural derivatives. Future prospects and further developments in this area are covered at the end of the review. The literature is covered to the end of August 2015. PMID:26969844

  20. The derivative of a continued fraction

    SciTech Connect

    Bowman, Kimiko o

    2009-01-01

    The paper considers second order continued fractions associated with (I) the Psi function {psi}(z), (II) the continued fraction component in ln {Gamma}(z) due to Stieltjes. The second order sequences k*{sub s}/k{sub s} provide approximants, some of which are remarkably close. In addition a series form for the convergent {chi}{sub s}={omega}{sub s} associated with a continued fraction provides an expression for the derivatives of a continued fraction. The implementation uses a Maple code for derivatives.

  1. Water-soluble derivatives of 1 -tetrahydrocannabinol.

    PubMed

    Zitko, B A; Howes, J F; Razdan, R K; Dalzell, B C; Dalzell, H C; Sheehan, J C; Pars, H G; Dewey, W L; Harris, L S

    1972-08-01

    Delta1-Tetrahydrocannabinol, which is resinous and insoluble in water and therefore difficult to study pharmacologically, can be converted to a watersoluble derivative without loss of its biological activity. This has been achieved by preparing esters bearing a nitrogen moiety with the use of carbodiimide as the condensing agent. The availability of such water-soluble derivatives will allow the evaluation of Delta1-tetrahydrocannabinol in self-administration studies in monkeys for its addiction liability potential in man. This technique of water solubilization is also applicable to other compounds of chemical and biological significance. PMID:5043146

  2. Photoluminescence in anthracene and it's derivatives

    NASA Astrophysics Data System (ADS)

    Vyas, Arpita; Mirgane, Nitin A.; Moharil, S. V.; Muley, Aarti Iyer

    2016-05-01

    The anthracene and it's derivative 9-chloro acridine and Anthracene-9-ylmethylacetate have prepared in Poly vinyl alcohol(PVOH). Their photoluminescence properties have studied. The pure anthracene has an emission at 424 and 443nm. The intense peak is observed at 465nm and shoulder at 407nm. The derivatives of anthracene Anthracene-9-ylmethylacetate shows an emission around 440nm for the excitation at 393nm and 9-chloro acridine shows emission around 360nm for the excitation at 290nm. The major problem of this organic material is the stability. The composites prepared in the medium of PVOH are more stable.

  3. Passerini Reactions on Biocatalytically Derived Chiral Azetidines.

    PubMed

    Moni, Lisa; Banfi, Luca; Basso, Andrea; Bozzano, Andrea; Spallarossa, Martina; Wessjohann, Ludger; Riva, Renata

    2016-01-01

    The purpose of this study was to explore a series of Passerini reactions on a biocatalytically derived enantiopure azetidine-2-carboxyaldehyde in order to obtain, in a diastereoselective manner, polyfunctionalised derivatives having the potential to be cyclized to chiral bridged bicyclic nitrogen heterocycles. While diastereoselectivity was poor under classical Passerini conditions, a significant increase of diastereoselectivity (up to 76:24) was gained by the use of zinc bromide as promoter. The methodology has a broad scope and yields are always good. PMID:27589709

  4. High ethanol producing derivatives of Thermoanaerobacter ethanolicus

    DOEpatents

    Ljungdahl, Lars G.; Carriera, Laura H.

    1983-01-01

    Derivatives of the newly discovered microorganism Thermoanaerobacter ethanolicus which under anaerobic and thermophilic conditions continuously ferment substrates such as starch, cellobiose, glucose, xylose and other sugars to produce recoverable amounts of ethanol solving the problem of fermentations yielding low concentrations of ethanol using the parent strain of the microorganism Thermoanaerobacter ethanolicus are disclosed. These new derivatives are ethanol tolerant up to 10% (v/v) ethanol during fermentation. The process includes the use of an aqueous fermentation medium, containing the substrate at a substrate concentration greater than 1% (w/v).

  5. High ethanol producing derivatives of Thermoanaerobacter ethanolicus

    DOEpatents

    Ljungdahl, L.G.; Carriera, L.H.

    1983-05-24

    Derivatives of the newly discovered microorganism Thermoanaerobacter ethanolicus which under anaerobic and thermophilic conditions continuously ferment substrates such as starch, cellobiose, glucose, xylose and other sugars to produce recoverable amounts of ethanol solving the problem of fermentations yielding low concentrations of ethanol using the parent strain of the microorganism Thermoanaerobacter ethanolicus are disclosed. These new derivatives are ethanol tolerant up to 10% (v/v) ethanol during fermentation. The process includes the use of an aqueous fermentation medium, containing the substrate at a substrate concentration greater than 1% (w/v).

  6. Elevation Derivatives for Mojave Desert Tortoise Habitat

    USGS Publications Warehouse

    Wallace, Cynthia S.A.; Gass, Leila

    2008-01-01

    This report describes the methods used to derive various elevation-derivative grids that were inputted to the Mojave Desert Tortoise Habitat model (L. Gass and others, unpub. data). These grids, which capture information on surface roughness and topographic characteristics, are a subset of the environmental datasets evaluated for the tortoise habitat model. This habitat model is of major importance to the U.S. Fish and Wildlife Service, which is charged with management of this threatened population, including relocating displaced tortoises to areas identified as suitable habitat.

  7. Geometric derivation of the quantum speed limit

    SciTech Connect

    Jones, Philip J.; Kok, Pieter

    2010-08-15

    The Mandelstam-Tamm and Margolus-Levitin inequalities play an important role in the study of quantum-mechanical processes in nature since they provide general limits on the speed of dynamical evolution. However, to date there has been only one derivation of the Margolus-Levitin inequality. In this paper, alternative geometric derivations for both inequalities are obtained from the statistical distance between quantum states. The inequalities are shown to hold for unitary evolution of pure and mixed states, and a counterexample to the inequalities is given for evolution described by completely positive trace-preserving maps. The counterexample shows that there is no quantum speed limit for nonunitary evolution.

  8. Bistacrine derivatives as new potent antimalarials.

    PubMed

    Schmidt, Ines; Pradel, Gabriele; Sologub, Ludmilla; Golzmann, Alexandra; Ngwa, Che J; Kucharski, Anna; Schirmeister, Tanja; Holzgrabe, Ulrike

    2016-08-15

    Linking two tacrine molecules results in a tremendous increase of activity against Plasmodia in comparison to the monomer. This finding prompted the synthesis of a library of monomeric and dimeric tacrine derivatives in order to derive structure-activity relationships. The most active compounds towards chloroquine sensitive Plasmodium strain 3D7 and chloroquine resistant strain Dd2 show IC50 values in the nanomolar range of concentration, low cytotoxicity and target the cysteine protease falcipain-2, which is essential for parasite growth. PMID:27316542

  9. Special relativity derived from spacetime magma.

    PubMed

    Greensite, Fred

    2014-01-01

    We present a derivation of relativistic spacetime largely untethered from specific physical considerations, in constrast to the many physically-based derivations that have appeared in the last few decades. The argument proceeds from the inherent magma (groupoid) existing on the union of spacetime frame components [Formula: see text] and Euclidean [Formula: see text] which is consistent with an "inversion symmetry" constraint from which the Minkowski norm results. In this context, the latter is also characterized as one member of a class of "inverse norms" which play major roles with respect to various unital [Formula: see text]-algebras more generally. PMID:24959889

  10. Structural studies of 4-aminoantipyrine derivatives

    NASA Astrophysics Data System (ADS)

    Cunha, Silvio; Oliveira, Shana M.; Rodrigues, Manoel T.; Bastos, Rodrigo M.; Ferrari, Jailton; de Oliveira, Cecília M. A.; Kato, Lucília; Napolitano, Hamilton B.; Vencato, Ivo; Lariucci, Carlito

    2005-10-01

    Reaction of 4-aminoantipyrine with acetylacetone, ethyl acetoacetate, benzoyl isothiocyanate, phenyl isothiocyanate, maleic anhydride and methoxymethylene Meldrum's acid afforded a series of new antipyrine derivatives. The antibacterial activity of the synthesized compounds against Micrococcus luteus ATCC 9341, Staphilococcus aureus ATCC 29737, and Escherichia coli ATCC 8739 was evaluated and the minimal inhibitory concentration determined. Modest activity was found only to the maleamic acid obtained from the reaction of 4-aminoantipyrine and maleic anhydride. 1H NMR investigation of this maleamic acid showed that it is slowly converted to the corresponding toxic maleimide. The structures of three derivatives were determined by X-ray diffraction analysis.

  11. Terpenes from Marine-Derived Fungi

    PubMed Central

    Ebel, Rainer

    2010-01-01

    Terpenes from marine-derived fungi show a pronounced degree of structural diversity, and due to their interesting biological and pharmacological properties many of them have aroused interest from synthetic chemists and the pharmaceutical industry alike. The aim of this paper is to give an overview of the structural diversity of terpenes from marine-derived fungi, highlighting individual examples of chemical structures and placing them in a context of other terpenes of fungal origin. Wherever possible, information regarding the biological activity is presented. PMID:20948911

  12. Optimal economic order quantity for buyer-distributor-vendor supply chain with backlogging derived without derivatives

    NASA Astrophysics Data System (ADS)

    Teng, Jinn-Tsair; Cárdenas-Barrón, Leopoldo Eduardo; Lou, Kuo-Ren; Wee, Hui Ming

    2013-05-01

    In this article, we first complement an inappropriate mathematical error on the total cost in the previously published paper by Chung and Wee [2007, 'Optimal the Economic Lot Size of a Three-stage Supply Chain With Backlogging Derived Without Derivatives', European Journal of Operational Research, 183, 933-943] related to buyer-distributor-vendor three-stage supply chain with backlogging derived without derivatives. Then, an arithmetic-geometric inequality method is proposed not only to simplify the algebraic method of completing prefect squares, but also to complement their shortcomings. In addition, we provide a closed-form solution to integral number of deliveries for the distributor and the vendor without using complex derivatives. Furthermore, our method can solve many cases in which their method cannot, because they did not consider that a squared root of a negative number does not exist. Finally, we use some numerical examples to show that our proposed optimal solution is cheaper to operate than theirs.

  13. Antibacterial anthraquinone derivatives from a sea anemone-derived fungus Nigrospora sp.

    PubMed

    Yang, Kai-Lin; Wei, Mei-Yan; Shao, Chang-Lun; Fu, Xiu-Mei; Guo, Zhi-Yong; Xu, Ru-Fang; Zheng, Cai-Juan; She, Zhi-Gang; Lin, Yong-Cheng; Wang, Chang-Yun

    2012-05-25

    Chemical investigation of a marine-derived fungus Nigrospora sp., isolated from an unidentified sea anemone, yielded two new hydroanthraquinone analogues, 4a-epi-9α-methoxydihydrodeoxybostrycin (1) and 10-deoxybostrycin (2), together with seven known anthraquinone derivatives (3-9). The structures of the two new compounds were established through extensive NMR spectroscopy as well as a single-crystal X-ray diffraction analysis using Cu Kα radiation. The antibacterial activities of compounds 1-9 and 10 acetyl derivatives (6a, 7a, 8a-8g, 9a) were evaluated in vitro. Compound 6a, the acetylated derivative of 6, exhibited promising activity against Bacillus cereus with an MIC value of 48.8 nM, which was stronger than that of the positive control ciprofloxacin (MIC = 1250 nM). Analysis of the antibacterial screening data for the metabolites and their acetyl derivatives revealed the key structural features required for this activity. PMID:22545792

  14. Synthesis of hydroxy derivatives of limonene

    NASA Astrophysics Data System (ADS)

    Ardashov, O. V.; Volcho, K. P.; Salakhutdinov, N. F.

    2014-04-01

    Synthetic routes to mono-, di- and trihydroxy derivatives of limonene are presented. Emphasis is given to the problems of regio- and stereoselectivity of transformations. Data on the isolation from natural sources and on the biological activities of the title compounds are given. The bibliography includes 107 references.

  15. Polyprenylated benzophenone derivatives from Cuban propolis.

    PubMed

    Hernández, Ingrid Márquez; Fernandez, Mercedes Campo; Cuesta-Rubio, Osmany; Piccinelli, Anna Lisa; Rastrelli, Luca

    2005-06-01

    Three new polyprenylated benzophenone derivatives, propolones B-D (5-7), together with garcinielliptone I (8) and hyperibone B (9), were isolated from Cuban propolis. All the structures, including relative configurations, were elucidated by spectroscopic methods and computer-generated molecular modeling. PMID:15974622

  16. Three new bibenzyl derivatives from Dendrobium nobile.

    PubMed

    Zhang, Xue; Gao, Hao; Wang, Nai-Li; Yao, Xin-Sheng

    2006-01-01

    Three new bibenzyl derivatives have been isolated from the stems of Dendrobium nobile Lindl. (Orchidaceae). Their structures were established as 4,5-dihydroxy-3,3',alpha-trimethoxybibenzyl (1), 4,4'-dihydroxy-3,3',5,alpha-tetramethoxybibenzyl (2) and 4-hydroxy-3,3',4',5,alpha-pentamethoxybibenzyl (3) on the basis of spectroscopic analysis. PMID:16753791

  17. An accelerated subspace iteration for eigenvector derivatives

    NASA Technical Reports Server (NTRS)

    Ting, Tienko

    1991-01-01

    An accelerated subspace iteration method for calculating eigenvector derivatives has been developed. Factors affecting the effectiveness and the reliability of the subspace iteration are identified, and effective strategies concerning these factors are presented. The method has been implemented, and the results of a demonstration problem are presented.

  18. Cellulose Derivatives for Water Repellent Properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this poster presentation, we will discuss the synthesis and structural characterizations of nitro-benzyl cellulose (1), amino-benzyl cellulose (2) and pentafluoro –benzyl cellulose (3). All cellulose derivatives are synthesized by etherification process in lithium chloride/N,N-dimethylacetamide h...

  19. Cellulose Derivatives for Water Repellent Properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Synthesis and structural characterizations of nitro-benzyl cellulose, amino-benzyl cellulose and pentafluoro –benzyl cellulose were carried out. Cellulose derivatives were synthesized by etherification process in lithium chloride/N,N-dimethylacetamide homogeneous solution. Nitrobenzylation was effec...

  20. Sol-Gel Derived Hafnia Coatings

    NASA Technical Reports Server (NTRS)

    Feldman, Jay D.; Stackpoole, Mairead; Blum, Yigal; Sacks, Michael; Ellerby, Don; Johnson, Sylvia M.; Venkatapathy, Ethiras (Technical Monitor)

    2002-01-01

    Sol-gel derived hafnia coatings are being developed to provide an oxidation protection layer on ultra-high temperature ceramics for potential use in turbine engines (ultra-efficient engine technology being developed by NASA). Coatings using hafnia sol hafnia filler particles will be discussed along with sol synthesis and characterization.

  1. Partial Derivative Automata Formalized in Coq

    NASA Astrophysics Data System (ADS)

    Almeida, José Bacelar; Moreira, Nelma; Pereira, David; de Sousa, Simão Melo

    In this paper we present a computer assisted proof of the correctness of a partial derivative automata construction from a regular expression within the Coq proof assistant. This proof is part of a formalization of Kleene algebra and regular languages in Coq towards their usage in program certification.

  2. Two-point derivative dispersion relations

    NASA Astrophysics Data System (ADS)

    Ferreira, Erasmo; Sesma, Javier

    2013-03-01

    A new derivation is given for the representation, under certain conditions, of the integral dispersion relations of scattering theory through local forms. The resulting expressions have been obtained through an independent procedure to construct the real part and consist of new mathematical structures of double infinite summations of derivatives. In this new form the derivatives are calculated at the generic value of the energy E and separately at the reference point E = m that is the lower limit of the integration. This new form may be more interesting in certain circumstances and directly shows the origin of the difficulties in convergence that were present in the old truncated forms called standard-derivative dispersion relations (DDR). For all cases in which the reductions of the double to single sums were obtained in our previous work, leading to explicit demonstration of convergence, these new expressions are seen to be identical to the previous ones. We present, as a glossary, the most simplified explicit results for the DDR's in the cases of imaginary amplitudes of forms (E/m)λ[ln (E/m)]n that cover the cases of practical interest in particle physics phenomenology at high energies. We explicitly study the expressions for the cases with λ negative odd integers, that require identification of cancelation of singularities, and provide the corresponding final results.

  3. Deriving a Pedagogy of Educational Foundations

    ERIC Educational Resources Information Center

    Fenstermacher, Gary D.

    2007-01-01

    This sixth and last paper in the series describes four elements believed to be crucial to a high quality pedagogy for educational foundations. These four elements are derived from a close reading of the previous papers. The work of Osguthorpe, Sanger, Haniford, and Mucher, four of the authors in this series, is cited as both a source for these…

  4. Ecosystem Services Derived from Headwater Catchments

    EPA Science Inventory

    We used data from the USEPA’s wadeable streams assessment (WSA), US Forest Service’s forest inventory and analysis (FIA), and select USFS experimental forests (EF) to investigate potential ecosystems services derived from headwater catchments. C, N, and P inputs to these catchmen...

  5. Alternative Derivations for the Poisson Integral Formula

    ERIC Educational Resources Information Center

    Chen, J. T.; Wu, C. S.

    2006-01-01

    Poisson integral formula is revisited. The kernel in the Poisson integral formula can be derived in a series form through the direct BEM free of the concept of image point by using the null-field integral equation in conjunction with the degenerate kernels. The degenerate kernels for the closed-form Green's function and the series form of Poisson…

  6. A new benzofuran derivative from Nicotiana tabacum.

    PubMed

    Xia, Jian-Jun; Li, Yuan-Dong; Liu, Xiu-Ming; Lu, Yuan; Wu, Yi-Qin; Qin, Yun-Hua

    2016-08-01

    A new benzofuran derivative, methyl 3-acetyl-7-hydroxy-6-methoxy-2-methylbenzofuran-4-carboxylate (1), and a known compound pyrrolezanthine (2), were isolated from leaves of Nicotiana tabacum. Compound 1 was elucidated by means of spectroscopic methods, as well as X-ray diffraction. Both compounds 1 and 2 exhibited moderate inhibitory activities on human cancer cell lines. PMID:26982907

  7. Constraining higher derivative supergravity with scattering amplitudes

    SciTech Connect

    Wang, Yifan; Yin, Xi

    2015-08-31

    We study supersymmetry constraints on higher derivative deformations of type IIB supergravity by consideration of superamplitudes. Thus, combining constraints of on-shell supervertices and basic results from string perturbation theory, we give a simple argument for the non-renormalization theorem of Green and Sethi, and some of its generalizations.

  8. 18 CFR 1301.65 - Derivative classification.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... classification. 1301.65 Section 1301.65 Conservation of Power and Water Resources TENNESSEE VALLEY AUTHORITY... record copy. (c) Documents classified derivatively shall bear all markings prescribed by 32 CFR 2001.20 through 2001.23 and shall otherwise conform to the requirements of 32 CFR 2001.20 through 2001.23....

  9. 18 CFR 1301.65 - Derivative classification.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... classification. 1301.65 Section 1301.65 Conservation of Power and Water Resources TENNESSEE VALLEY AUTHORITY... record copy. (c) Documents classified derivatively shall bear all markings prescribed by 32 CFR 2001.20 through 2001.23 and shall otherwise conform to the requirements of 32 CFR 2001.20 through 2001.23....

  10. 18 CFR 1301.65 - Derivative classification.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... classification. 1301.65 Section 1301.65 Conservation of Power and Water Resources TENNESSEE VALLEY AUTHORITY... record copy. (c) Documents classified derivatively shall bear all markings prescribed by 32 CFR 2001.20 through 2001.23 and shall otherwise conform to the requirements of 32 CFR 2001.20 through 2001.23....