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1

An unprecedented octahedral {Cd30} nanocage supported by twelve pendant-armed tetraacetate macrocyclic ligands.  

UK PubMed Central (United Kingdom)

An unprecedented octahedral {Cd(30)} nanocage supported by twelve pendant-armed tetraacetate macrocyclic ligands was synthesized through the reaction of macrocyclic tetraethyl ester and Cd(OAc)(2)·2H(2)O in a 1?:?2 stoichiometry, where the surface photovoltage and photoluminescent properties have been studied for the nanocage.

Gong WJ; Liu YY; Yang J; Wu H; Ma JF; Xie TF

2013-03-01

2

DOTASA, an Asymmetrical Derivative of DOTA Substituted at one Acetate pendant Arm: 1H NMR and Potentiometric Studies of the Ligand and its Lanthanide(III) Complexes  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The ligand H5dotasa (=(alphaRS)-alpha-(carboxymethyl)-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) is a H4dota-like macrocyclic ligand with a carboxymethyl CH2COOH substituent moiety at the C(alpha) atom of one of the four acetate pendant arms of H4dota (=1,4,7,10-tetraazacyclododecane-...

André, João P.; Brücher, Ernö; Kiraly, Robert; Carvalho, Rui A.; Mäcke, Helmut; Geraldes, Carlos F. G. C.

3

Biological evaluation of 153Sm and 166Ho complexes with macrocyclic ligands containing acetate pendant arms as potential agents for therapy  

International Nuclear Information System (INIS)

[en] For the development of therapeutic radiopharmaceuticals it is essential to choose the appropriate beta-emitter as well as the carrier biomolecule. Different carrier biomolecules, namely antibodies and peptides, have been linked to different beta-emitters (153Sm, 166Ho and 177Lu) using tetraaza macrocycles as bifunctional chelators. The cavity size of these chelators, the rigidity of the macrocyclic backbone and the nature of the pendant arms seems to play an important role on the thermodynamic stability and kinetic inertness of the radiocomplexes and on their biological behaviour. In our research group we have been exploring the possibility of using tetraazamacrocycles with different cavity size, pendant arms and rigidity for preparing 153Sm and 166Ho complexes useful for therapeutical applications and/or bone pain palliation. In this communication we present the results obtained when we reacted trita and teta with 153Sm and 166Ho. The complexes are formed in good yields (> 98%), are hydrophilic and present an overall negative charges, as well as low plasmatic protein binding. Good in vitro stability in physiological media and human serum was also found for all the complexes. The biodistribution studies in mice are also presented and have shown that 153Sm/166Ho-trita and 166Ho-teta have rapid tissue clearance, comparably to the corresponding dota complexes. In contrast, 153Sm-teta has a significant lower total excretion and a significant liver and muscle uptake. Our results indicate that 153Sm/166Ho-trita form very stable complexes in vivo. However, teta, which has a larger cavity size, forms less stable complexes with the larger ion Sm3+. The biological profile of 153Sm/166Ho-trita is very interesting for the evaluation of these complexes as therapeutical agents when conjugated to biomolecules

2005-01-01

4

Cyclen derivatives with two trans-methylnitrophenolic pendant arms: a structural study of their copper(II) and zinc(II) complexes.  

UK PubMed Central (United Kingdom)

Two new cyclen derivatives, H(2)do2nph and H(2)cb-do2nph, containing two trans-2-methyl-4-nitrophenol pendant arms and the latter including also an ethylene cross-bridge, were prepared in good yields using the bisaminal synthetic route. The two ligands were studied comparatively regarding their metal complexation behaviour. The copper(II) and zinc(II) complexes of H(2)do2nph and H(2)cb-do2nph were studied in dimethylsulfoxide-water (9 : 1 v/v) solution by a range of spectroscopic techniques. Copper(II) complexes were also studied in solid state by X-ray single crystal diffraction. These studies showed that the copper(II) and zinc(II) complexes of H(2)do2nph exhibited a distorted square pyramidal coordination environment with the four nitrogen atoms of the cyclen ring defining the basal plane, and that one of the nitrophenolate arms did not coordinate to the metal, independently of its protonation state. On the other hand, depending on the protonation state of one of the nitrophenolic arms, the cross-bridged derivative forms copper(II) complexes with distorted square pyramidal or octahedral geometries with one or two arms coordinated to the metal centre, respectively. In the complex with distorted octahedral geometry, the two phenolic oxygen atoms are coordinated to the metal centre in a cis-fashion. Acid-assisted dissociation assays in 1 mol dm(-3) HCl DMSO-H(2)O (9 : 1 v/v) solution at 298.2 K allowed one to determine the half-life of both copper(II) complexes, which is lower for the derivative without a cross-bridge as expected, while for the other one it is quite high and in line with similar cross-bridged cyclen derivatives from the literature.

Esteves CV; Lima LM; Mateus P; Delgado R; Brandão P; Félix V

2013-05-01

5

Uranyl complexes formed with a para-t-butylcalix[4]arene bearing phosphinoyl pendant arms on the lower rim. Solid and solution studies  

International Nuclear Information System (INIS)

The current interest in functionalized calixarenes with phosphorylated pendant arms resides in their coordination ability towards f elements and capability towards actinide/rare earth separation. Uranyl cation forms 1:1 and 1:2 (M:L) complexes with a tetra-phosphinoylated p-tert-butylcalix[4]arene, B4bL4: UO2(NO3)2(B4bL4)n . xH2O (n = 1, x = 2, 1; n = 2, x = 6, 2). Spectroscopic data point to the inner coordination sphere of 1 containing one monodentate nitrate anion, one water molecule and the four phosphinoylated arms bound to UO22+ while in 2, uranyl is only coordinated to calixarene ligands. In both cases the U(VI) ion is 8-coordinate. Uranyl complexes display enhanced metal-centred luminescence due to energy transfer from the calixarene ligands; the luminescence decays are bi-exponential with associated lifetimes in the ranges 220 ?s s L 5/2,7/2), O(1s) and P(2p) levels on solid state samples. The extraction study of UO22+ cation and trivalent rare-earth (Y, La, Eu) ions from acidic nitrate media by B4bL4 in chloroform shows the uranyl cation being much more extracted than rare earths. (orig.)

2012-01-01

6

Nickel complexes incorporating an amido phosphine chelate with a pendant amine arm: synthesis, structure, and catalytic Kumada coupling.  

Science.gov (United States)

A series of organonickel(II) complexes incorporating an amido phosphine ligand tethered with an amino pendant have been prepared and characterized. Deprotonation of N-(dimethylaminoethyl)-2-diphenylphosphinoaniline (H[PNN]) with one equivalent of n-BuLi in ethereal or hydrocarbon solutions at -35 °C generates cleanly dimeric {Li[PNN]}(2) as yellow crystals. The reaction of NiCl(2)(DME) with {Li[PNN]}(2) in THF at -35 °C affords green crystalline [PNN]NiCl. Treating [PNN]NiCl with NaX in acetone solutions gives [PNN]NiX (X = Br, I). Alkylation or arylation of [PNN]NiCl with appropriate Grignard reagents in THF at -35 °C produces red crystalline [PNN]NiR (R = Me, Et, i-Bu, n-hexyl, CH(2)Ph, Ph). The chloride complex [PNN]NiCl was found to be an active catalyst precursor for Kumada coupling reactions of PhX (X = I, Br, Cl) with aryl or alkyl Grignard reagents, including those containing ?-hydrogen atoms. The X-ray structures of {Li[PNN]}(2) and [PNN]NiX (X = Cl, Br, Me, Et, n-hexyl) are reported. PMID:22124467

Liang, Lan-Chang; Lee, Wei-Ying; Hung, Yu-Ting; Hsiao, Yi-Chen; Cheng, Liang-Chien; Chen, Wei-Chen

2011-11-29

7

Uranyl complexes formed with a para-t-butylcalix[4]arene bearing phosphinoyl pendant arms on the lower rim. Solid and solution studies  

Energy Technology Data Exchange (ETDEWEB)

The current interest in functionalized calixarenes with phosphorylated pendant arms resides in their coordination ability towards f elements and capability towards actinide/rare earth separation. Uranyl cation forms 1:1 and 1:2 (M:L) complexes with a tetra-phosphinoylated p-tert-butylcalix[4]arene, B{sub 4}bL{sup 4}: UO{sub 2}(NO{sub 3}){sub 2}(B{sub 4}bL{sup 4}){sub n} . xH{sub 2}O (n = 1, x = 2, 1; n = 2, x = 6, 2). Spectroscopic data point to the inner coordination sphere of 1 containing one monodentate nitrate anion, one water molecule and the four phosphinoylated arms bound to UO{sub 2}{sup 2+} while in 2, uranyl is only coordinated to calixarene ligands. In both cases the U(VI) ion is 8-coordinate. Uranyl complexes display enhanced metal-centred luminescence due to energy transfer from the calixarene ligands; the luminescence decays are bi-exponential with associated lifetimes in the ranges 220 {mu}s < {tau}{sub s} < 250 {mu}s and 630 {mu}s < {tau}{sub L} < 640 {mu}s, pointing to the presence of two species with differently coordinated calixarene, as substantiated by a XPS study of U(4f{sub 5/2,7/2}), O(1s) and P(2p) levels on solid state samples. The extraction study of UO{sub 2}{sup 2+} cation and trivalent rare-earth (Y, La, Eu) ions from acidic nitrate media by B{sub 4}bL{sup 4} in chloroform shows the uranyl cation being much more extracted than rare earths. (orig.)

Ramirez, F. de M. [Instituto Nacional de Investigaciones Nucleares, La Marquesa, Ocoyoacac (Mexico). Dept. de Quimica; Varbanov, S. [Bulgarian Academy of Sciences, Sofia (Bulgaria). Inst. of Organic Chemistry with Center of Phytochemistry; Buenzli, J.C.G. [Ecole Polytechnique Federale de Lausanne (EPFL) (Switzerland). Inst. of Chemical Sciences and Engineering; Rivas-Silva, J.F.; Ocana-Bribiesca, M.A. [Instituto de Fisica de la BUAP, Puebla (Mexico); Cortes-Jacome, M.A.; Toledo-Antonio, J.A. [Instituto Mexicano del Petroleo/Programa de Ingenieria Molecular (Mexico)

2012-07-01

8

Synthesis, Cu(II) complexation, 64Cu-labeling and biological evaluation of cross-bridged cyclam chelators with phosphonate pendant arms.  

UK PubMed Central (United Kingdom)

A new class of cross-bridged cyclam-based macrocycles featuring phosphonate pendant groups has been developed. 1,4,8,11-tetraazacyclotetradecane-1,8-di(methanephosphonic acid) (CB-TE2P, 1) and 1,4,8,11-tetraazacyclotetradecane-1-(methanephosphonic acid)-8-(methanecarboxylic acid) (CB-TE1A1P, 2) have been synthesized and have been shown to readily form neutral copper(II) complexes at room temperature as the corresponding dianions. Both complexes showed high kinetic inertness to demetallation and crystal structures confirmed complete encapsulation of copper(II) ion within each macrocycle's cleft-like structure. Unprecedented for cross-bridged cyclam derivatives, both CB-TE2P (1) and CB-TE1A1P (2) can be radiolabeled with (64)Cu at room temperature in less than 1 h with specific activities >1 mCi ?g(-1). The in vivo behavior of both (64)Cu-CB-TE2P and (64)Cu-CB-TE1A1P were investigated through biodistribution studies using healthy male Lewis rats. Both new compounds showed rapid clearance with similar or lower accumulation in non-target organs/tissues when compared to other copper chelators including CB-TE2A, NOTA and Diamsar.

Ferdani R; Stigers DJ; Fiamengo AL; Wei L; Li BT; Golen JA; Rheingold AL; Weisman GR; Wong EH; Anderson CJ

2012-02-01

9

Synthesis, Cu(II) complexation, 64Cu-labeling and biological evaluation of cross-bridged cyclam chelators with phosphonate pendant arms.  

Science.gov (United States)

A new class of cross-bridged cyclam-based macrocycles featuring phosphonate pendant groups has been developed. 1,4,8,11-tetraazacyclotetradecane-1,8-di(methanephosphonic acid) (CB-TE2P, 1) and 1,4,8,11-tetraazacyclotetradecane-1-(methanephosphonic acid)-8-(methanecarboxylic acid) (CB-TE1A1P, 2) have been synthesized and have been shown to readily form neutral copper(II) complexes at room temperature as the corresponding dianions. Both complexes showed high kinetic inertness to demetallation and crystal structures confirmed complete encapsulation of copper(II) ion within each macrocycle's cleft-like structure. Unprecedented for cross-bridged cyclam derivatives, both CB-TE2P (1) and CB-TE1A1P (2) can be radiolabeled with (64)Cu at room temperature in less than 1 h with specific activities >1 mCi ?g(-1). The in vivo behavior of both (64)Cu-CB-TE2P and (64)Cu-CB-TE1A1P were investigated through biodistribution studies using healthy male Lewis rats. Both new compounds showed rapid clearance with similar or lower accumulation in non-target organs/tissues when compared to other copper chelators including CB-TE2A, NOTA and Diamsar. PMID:22170043

Ferdani, Riccardo; Stigers, Dannon J; Fiamengo, Ashley L; Wei, Lihui; Li, Barbara T Y; Golen, James A; Rheingold, Arnold L; Weisman, Gary R; Wong, Edward H; Anderson, Carolyn J

2011-12-15

10

Cyclam kappa4 to kappa3 ligand denticity change upon mono-n-substitution with a carboxypropyl pendant arm in a ruthenium nitrosyl complex.  

UK PubMed Central (United Kingdom)

The complex fac-[Ru(NO)Cl2(kappa(3)N(4),N(8),N(11)(1-carboxypropyl)cyclam)]Cl.H2O (1-carboxypropyl)cyclam=3-(1,4,8,11-tetraazacyclotetradecan-1-yl)propionic acid) was prepared in a one pot reaction by mixing equimolar amounts of RuNOCl 3 and (1-carboxypropyl)cyclam and was characterized by X-ray crystallography, electrospray ionization tandem mass spectrometry (ESI-MS/MS), elemental analysis, NMR, and electronic and vibrational (IR) spectroscopies. fac-[Ru(NO)Cl 2(kappa(3)N(4),N(8),N(11)(1-carboxypropyl)cyclam)]Cl.H2O crystallizes in the triclinic, space group P1, No. 2, with unit cell parameters of a=8.501(1) A, b=9.157(1) A, c=14.200(1) A, alpha=72.564(5) degrees , beta=82.512(5) degrees , gamma=80.308(5) degrees , and Z=2. The Ru-N interatomic distance and bond angle in the [Ru-NO] unit are 1.739(2) A and 167.7(2) degrees , respectively. ESI-MS/MS shows characteristic dissociation chemistry that initiates by HCl or NO loss. The IR spectrum displays a nu(NO) at 1881 cm(-1) indicating a nitrosonium character. The electronic spectrum shows absorptions bands at 264 nm (log epsilon=3.27), 404 nm (log epsilon=2.53), and 532 nm (log epsilon=1.88). (1)H and (13)C NMR are in agreement with the proposed molecular structure, which shows a very singular architecture where the cyclam ring N (with the carboxypropyl pendant arm) is not coordinated to the ruthenium resulting in a kappa(3) instead of the expected kappa(4) denticity.

Doro FG; Castellano EE; Moraes LA; Eberlin MN; Tfouni E

2008-05-01

11

Cyclam kappa4 to kappa3 ligand denticity change upon mono-n-substitution with a carboxypropyl pendant arm in a ruthenium nitrosyl complex.  

Science.gov (United States)

The complex fac-[Ru(NO)Cl2(kappa(3)N(4),N(8),N(11)(1-carboxypropyl)cyclam)]Cl.H2O (1-carboxypropyl)cyclam=3-(1,4,8,11-tetraazacyclotetradecan-1-yl)propionic acid) was prepared in a one pot reaction by mixing equimolar amounts of RuNOCl 3 and (1-carboxypropyl)cyclam and was characterized by X-ray crystallography, electrospray ionization tandem mass spectrometry (ESI-MS/MS), elemental analysis, NMR, and electronic and vibrational (IR) spectroscopies. fac-[Ru(NO)Cl 2(kappa(3)N(4),N(8),N(11)(1-carboxypropyl)cyclam)]Cl.H2O crystallizes in the triclinic, space group P1, No. 2, with unit cell parameters of a=8.501(1) A, b=9.157(1) A, c=14.200(1) A, alpha=72.564(5) degrees , beta=82.512(5) degrees , gamma=80.308(5) degrees , and Z=2. The Ru-N interatomic distance and bond angle in the [Ru-NO] unit are 1.739(2) A and 167.7(2) degrees , respectively. ESI-MS/MS shows characteristic dissociation chemistry that initiates by HCl or NO loss. The IR spectrum displays a nu(NO) at 1881 cm(-1) indicating a nitrosonium character. The electronic spectrum shows absorptions bands at 264 nm (log epsilon=3.27), 404 nm (log epsilon=2.53), and 532 nm (log epsilon=1.88). (1)H and (13)C NMR are in agreement with the proposed molecular structure, which shows a very singular architecture where the cyclam ring N (with the carboxypropyl pendant arm) is not coordinated to the ruthenium resulting in a kappa(3) instead of the expected kappa(4) denticity. PMID:18399626

Doro, Fábio G; Castellano, Eduardo E; Moraes, Luiz A B; Eberlin, Marcos N; Tfouni, Elia

2008-04-10

12

A library of multifunctional polyesters with "peptide-like" pendant functional groups.  

UK PubMed Central (United Kingdom)

The synthesis and characterization of a library of modular multifunctional polyesters with pendant functional groups are described. The polyesters were synthesized at room temperature by carbodiimide-mediated polymerization of pendant functionalized diols and succinic acid. The pendant groups are designed to mimic the side chains of peptides, and it is shown that the physical properties of the polyesters can be modulated over a wide range by the choice of pendant groups. We also show that the pendant groups can be orthogonally functionalized with ligands such as fluorophores, poly(ethylene glycol) (PEG) or Arg-Gly-Asp (RGD).

Gokhale S; Xu Y; Joy A

2013-08-01

13

A library of multifunctional polyesters with "peptide-like" pendant functional groups.  

Science.gov (United States)

The synthesis and characterization of a library of modular multifunctional polyesters with pendant functional groups are described. The polyesters were synthesized at room temperature by carbodiimide-mediated polymerization of pendant functionalized diols and succinic acid. The pendant groups are designed to mimic the side chains of peptides, and it is shown that the physical properties of the polyesters can be modulated over a wide range by the choice of pendant groups. We also show that the pendant groups can be orthogonally functionalized with ligands such as fluorophores, poly(ethylene glycol) (PEG) or Arg-Gly-Asp (RGD). PMID:23789897

Gokhale, Sachin; Xu, Ying; Joy, Abraham

2013-07-02

14

MAGNETIC FLUX CONCENTRATING PENDANT  

UK PubMed Central (United Kingdom)

Pendants made of very high permeability material. In a preferred embodiment the high permeability material is a rod (2) made of permalloy. The rod (2) is glued into a silver cap (4) and a cord (6) is threaded through an eye in the cap (4) for hanging the amulet around a person's neck. In other embodiments the high permeability material is attached to a belt which is worn around the waist or upper portion of a person's body. The high permeability material concentrates the earth's natural magnetic fields close to the person's body. I refer to these embodiments as "earth energy amulets" since they concentrate these natural earth forces near the body of the wearer.

DEA Jack Y.

15

Facilitated photoreduction of ruthenium bis(4`-methylterpyridine) pendant myoglobin  

Energy Technology Data Exchange (ETDEWEB)

A synthetic heme bearing ruthenium bis(terpyridine) through a covalent bond was successfully prepared. Ruthenium bis(terpyridine) pendant myoglobin, which was synthesized by a conventional cofactor reconstitution method, was efficiently activated through a photoinduced electron-transfer reaction from the ruthenium complex to the heme center. No reaction occurred in the corresponding intermolecular reaction system. (author)

Hamachi, Itaru; Matsugi, Tomoaki; Tanaka, Shigeaki; Shinkai, Seiji [Kyushu Univ., Fukuoka (Japan). Faculty of Engineering

1996-06-01

16

Facilitated photoreduction of ruthenium bis(4'-methylterpyridine) pendant myoglobin  

International Nuclear Information System (INIS)

A synthetic heme bearing ruthenium bis(terpyridine) through a covalent bond was successfully prepared. Ruthenium bis(terpyridine) pendant myoglobin, which was synthesized by a conventional cofactor reconstitution method, was efficiently activated through a photoinduced electron-transfer reaction from the ruthenium complex to the heme center. No reaction occurred in the corresponding intermolecular reaction system. (author).

1996-01-01

17

Transannular oscillation of metal centers in the pendant arm macrocyclic complex [1,4,8,11-tetrakis(2-hydroxyethyl)-1,4,8,11-tetraazacyclotetradecane]mercury(II) and its lead(II) analogue. NMR study of the 13C natural abundance and specifically enriched complexes  

International Nuclear Information System (INIS)

[en] A 13C NMR study of [1,4,8,11-tetrakis(2-hydroxyethyl)-1,4,8,11-tetraazacyclotetradecane]mercury(II) and its lead(II) analogue, [M(THEC)]2+ (M = Hg, Pb), in CD3OD, shows that the most probable structure of these complexes in solution incorporates the 1,4,8,11-tetraazacyclotetradecane ring in the trans III configurations with the metal center above the tetraaza plane and trigonal-prismatically coordinated by four ring nitrogens and two hydroxyethyl pendant arms attached to either end of the same 1,3-diaminopropane moiety. Dynamic 13C NMR studies of [M(THEC)]2+ are consistent with a rapid pairwise intramolecular exchange of the hydroxyethyl arms between mono- and bidentate coordination simultaneously with the oscillation of M(II) through the macrocyclic annulus of THEC. This pairwise exchange of the hydroxyethyl arms is characterized by k(298.2 K) = 3,130 ± 120 and 11,220 ± 200 s-1, ?H double-dagger = 38.0 ± 0.6 and 45.4 ± 0.3 kJ mol-1, and ?S double-dagger = -50.6 ± 2.1 and -15.2 ± 1.1 J K-1 mol-1, respectively, for M = Hg and Pb. 24 refs., 8 figs., 1 tab

1991-01-01

18

Thermodynamic and structural properties of Eu3+ complexes of a new 12-membered tetraaza macrocycle containing pyridine and N-glutaryl groups as pendant arms: characterization of three complexing successive phases.  

Science.gov (United States)

A new polyazamacrocyclic ligand (called pctga) containing pyridine and N-glutaryl arms has been synthesized as a potential agent for MRI (magnetic resonance imaging). Three series of successive complexes formed with Eu(3+) were characterized by at least two of the following methods: potentiometry, EXAFS or luminescence spectrometry. In the immediate complexes [EuH(h)(pctga)(H2O)6](h-3)+**, the metal ion is bound to the oxygen atoms of the three internal carboxylate groups and to six water molecules. As the lanthanide moves into the macrocyclic cavity, these species rapidly evolve into the intermediate metastable complexes [EuH(h)(pctga)(H2O)4](h-3)+*. The formation of two new bonds with the nitrogen atoms of the tetraazamacrocycle decreased the number of coordinated water molecules to four. In the final thermodynamically stable complexes [EuH(h)(pctga)(H2O)(2)](h-3)+, the pctga is bound to the europium(III) in a heptadentate manner, via the four nitrogen atoms of the tetraazamacrocycle and the three oxygen atoms of the internal carboxylate groups. The coordination number of the metal ion is completed to nine with two inner-sphere water molecules. The mean hydration numbers were calculated from the values of the bimolecular quenching constant k(q) of the luminescence species. The thermodynamic parameters corresponding to the protonation constants of the ligand and to the formation constants of the various intermediate and final complexes were determined from potentiometric measurements. They show that the complex species have some specific thermodynamic and structural properties inherent to the N-glutaryl groups and to the pyridine cycle. The insertion of this aromatic substructure rigidifies the ligand and sensibly diminishes the value of the overall formation constant (log beta(110) = 18.66(5)). This whole study allows us to propose a complexation mechanism for the system Eu(3+)/pctga in solution which is a mixture of the ones determined for the ligands dota and tced. PMID:17426863

Moreau, Juliette; Pierrard, Jean-Claude; Rimbault, Jean; Guillon, Emmanuel; Port, Marc; Aplincourt, Michel

2007-03-14

19

Carbon-13 and cadmium-113 nuclear magnetic resonance evidence for a novel transannular oscillation of cadmium(II) in the pendant arm macrocyclic complex [1,4,8,11-tetrakis(2-hydroxyethyl)-1,4,8,11-tetraazacyclotetradecane]cadmium(II)  

International Nuclear Information System (INIS)

[en] A 13C NMR study of [1,4,8,11-tetrakis(2-hydroxyethyl)-1,4,8,11-tetraazacyclotetradecane]cadmium(II), [Cd(THEC)]2+, in CD3OD shows that the most probable structure for [Cd(THEC)]2+ incorporates the 1,4,8,11-tetraazacyclotetradecane ring in the trans III configuration. In this structure Cd(II) is above the tetraaza plane and is trigonal-prismatically coordinated by four ring nitrogens and two hydroxyethyl pendant arms attached to either end of the same 1,3-diaminopropane moiety. The 13C CPMAS NMR spectrum of solid [Cd(THEC)]2+ is also consistent with this structure. Dynamic 13C NMR studies of natural abundance [Cd(THEC)]2+ and of [Cd(THEC)]2+ in which both carbons of each of the hydroxyethyl arms are 99 atom % enriched in 13C are consistent with a rapid oscillation of Cd(II) through the macrocyclic annulus of THEC. The 13C-enriched hydroxyethyl arms are characterized by 13C AB quartets under conditions of slow exchange but show a novel coalescence to a singlet under fast-exchange conditions consistent with the relative chemical shifts of the methylene carbons of the hydroxyethyl arm being reversed when it changes from the mono- to the bidentate coordination state. The pairwise exchange of the hydroxyethyl arm between the monodentate and bidentate environments is characterized by k(298.2 K) = 34,200 ± 1,800 s-1, ?H double-dagger = 44.00 ± 0.56 kJ mol-1, and ?S double-dagger = -10.6 ± 2.2 J K-1 mol-1. 13C and 113Cd NMR spectra show that intermolecular THEC and Cd(II) exchange on [Cd(THEC)]2+ is a much slower process. 29 refs., 6 figs

1990-05-16

20

Transannular oscillation of metal centers in the pendant arm macrocyclic complex (1,4,8,11-tetrakis(2-hydroxyethyl)-1,4,8,11-tetraazacyclotetradecane)mercury(II) and its lead(II) analogue. NMR study of the sup 13 C natural abundance and specifically enriched complexes  

Energy Technology Data Exchange (ETDEWEB)

A {sup 13}C NMR study of (1,4,8,11-tetrakis(2-hydroxyethyl)-1,4,8,11-tetraazacyclotetradecane)mercury(II) and its lead(II) analogue, (M(THEC)){sup 2+} (M = Hg, Pb), in CD{sub 3}OD, shows that the most probable structure of these complexes in solution incorporates the 1,4,8,11-tetraazacyclotetradecane ring in the trans III configurations with the metal center above the tetraaza plane and trigonal-prismatically coordinated by four ring nitrogens and two hydroxyethyl pendant arms attached to either end of the same 1,3-diaminopropane moiety. Dynamic {sup 13}C NMR studies of (M(THEC)){sup 2+} are consistent with a rapid pairwise intramolecular exchange of the hydroxyethyl arms between mono- and bidentate coordination simultaneously with the oscillation of M(II) through the macrocyclic annulus of THEC. This pairwise exchange of the hydroxyethyl arms is characterized by k(298.2 K) = 3,130 {plus minus} 120 and 11,220 {plus minus} 200 s{sup {minus}1}, {Delta}H{double dagger} = 38.0 {plus minus} 0.6 and 45.4 {plus minus} 0.3 kJ mol{sup {minus}1}, and {Delta}S{double dagger} = {minus}50.6 {plus minus} 2.1 and {minus}15.2 {plus minus} 1.1 J K{sup {minus}1} mol{sup {minus}1}, respectively, for M = Hg and Pb. 24 refs., 8 figs., 1 tab.

Clarke, P.; Lincoln, S.F. (Univ. of Adelaide (Australia)); Wainwright, K.P. (Flinders Univ. of South Australia, Bedford Park (Australia))

1991-01-01

 
 
 
 
21

Carbon-13 and cadmium-113 nuclear magnetic resonance evidence for a novel transannular oscillation of cadmium(II) in the pendant arm macrocyclic complex (1,4,8,11-tetrakis(2-hydroxyethyl)-1,4,8,11-tetraazacyclotetradecane)cadmium(II)  

Energy Technology Data Exchange (ETDEWEB)

A {sup 13}C NMR study of (1,4,8,11-tetrakis(2-hydroxyethyl)-1,4,8,11-tetraazacyclotetradecane)cadmium(II), (Cd(THEC)){sup 2+}, in CD{sub 3}OD shows that the most probable structure for (Cd(THEC)){sup 2+} incorporates the 1,4,8,11-tetraazacyclotetradecane ring in the trans III configuration. In this structure Cd(II) is above the tetraaza plane and is trigonal-prismatically coordinated by four ring nitrogens and two hydroxyethyl pendant arms attached to either end of the same 1,3-diaminopropane moiety. The {sup 13}C CPMAS NMR spectrum of solid (Cd(THEC)){sup 2+} is also consistent with this structure. Dynamic {sup 13}C NMR studies of natural abundance (Cd(THEC)){sup 2+} and of (Cd(THEC)){sup 2+} in which both carbons of each of the hydroxyethyl arms are 99 atom % enriched in {sup 13}C are consistent with a rapid oscillation of Cd(II) through the macrocyclic annulus of THEC. The {sup 13}C-enriched hydroxyethyl arms are characterized by {sup 13}C AB quartets under conditions of slow exchange but show a novel coalescence to a singlet under fast-exchange conditions consistent with the relative chemical shifts of the methylene carbons of the hydroxyethyl arm being reversed when it changes from the mono- to the bidentate coordination state. The pairwise exchange of the hydroxyethyl arm between the monodentate and bidentate environments is characterized by k(298.2 K) = 34,200 {plus minus} 1,800 s{sup {minus}1}, {Delta}H{double dagger} = 44.00 {plus minus} 0.56 kJ mol{sup {minus}1}, and {Delta}S{double dagger} = {minus}10.6 {plus minus} 2.2 J K{sup {minus}1} mol{sup {minus}1}. {sup 13}C and {sup 113}Cd NMR spectra show that intermolecular THEC and Cd(II) exchange on (Cd(THEC)){sup 2+} is a much slower process. 29 refs., 6 figs.

Clarke, P.; Hounslow, A.M.; Lincoln, S.F. (Univ. of Adelaide, South Australia (Australia)); Keough, R.A.; Wainwright, K.P. (Flinders Univ. of South Australia, Bedford Park (Australia))

1990-05-16

22

Synthesis and photooxidation of styrene copolymer bearing camphorquinone pendant groups.  

UK PubMed Central (United Kingdom)

(±)-10-Methacryloyloxycamphorquinone (MCQ) was synthesized from (±)-10-camphorsulfonic acid either by a known seven-step synthetic route or by a novel, shorter five-step synthetic route. MCQ was copolymerized with styrene (S) and the photochemical behavior of the copolymer MCQ/S was compared with that of a formerly studied copolymer of styrene with monomers containing the benzil (BZ) moiety (another 1,2-dicarbonyl). Irradiation (? > 380 nm) of aerated films of styrene copolymers with monomers containing the BZ moiety leads to the insertion of two oxygen atoms between the carbonyl groups of BZ and to the formation of benzoyl peroxide (BP) as pendant groups on the polymer backbone. An equivalent irradiation of MCQ/S led mainly to the insertion of only one oxygen atom between the carbonyl groups of camphorquinone (CQ) and to the formation of camphoric anhydride (11) covalently bound to the polymer backbone. While the decomposition of pendant BP groups formed in irradiated films of styrene copolymers with pendant BZ groups leads to crosslinking, only small molecular-weight changes in irradiated MCQ/S were observed.

Husár B; Moszner N; Luká? I

2012-01-01

23

Synthesis and photooxidation of styrene copolymer bearing camphorquinone pendant groups  

Directory of Open Access Journals (Sweden)

Full Text Available (±)-10-Methacryloyloxycamphorquinone (MCQ) was synthesized from (±)-10-camphorsulfonic acid either by a known seven-step synthetic route or by a novel, shorter five-step synthetic route. MCQ was copolymerized with styrene (S) and the photochemical behavior of the copolymer MCQ/S was compared with that of a formerly studied copolymer of styrene with monomers containing the benzil (BZ) moiety (another 1,2-dicarbonyl). Irradiation (? > 380 nm) of aerated films of styrene copolymers with monomers containing the BZ moiety leads to the insertion of two oxygen atoms between the carbonyl groups of BZ and to the formation of benzoyl peroxide (BP) as pendant groups on the polymer backbone. An equivalent irradiation of MCQ/S led mainly to the insertion of only one oxygen atom between the carbonyl groups of camphorquinone (CQ) and to the formation of camphoric anhydride (11) covalently bound to the polymer backbone. While the decomposition of pendant BP groups formed in irradiated films of styrene copolymers with pendant BZ groups leads to crosslinking, only small molecular-weight changes in irradiated MCQ/S were observed.

Branislav Husár; Norbert Moszner; Ivan Luká?

2012-01-01

24

Synthesis and photooxidation of styrene copolymer bearing camphorquinone pendant groups.  

Science.gov (United States)

(±)-10-Methacryloyloxycamphorquinone (MCQ) was synthesized from (±)-10-camphorsulfonic acid either by a known seven-step synthetic route or by a novel, shorter five-step synthetic route. MCQ was copolymerized with styrene (S) and the photochemical behavior of the copolymer MCQ/S was compared with that of a formerly studied copolymer of styrene with monomers containing the benzil (BZ) moiety (another 1,2-dicarbonyl). Irradiation (? > 380 nm) of aerated films of styrene copolymers with monomers containing the BZ moiety leads to the insertion of two oxygen atoms between the carbonyl groups of BZ and to the formation of benzoyl peroxide (BP) as pendant groups on the polymer backbone. An equivalent irradiation of MCQ/S led mainly to the insertion of only one oxygen atom between the carbonyl groups of camphorquinone (CQ) and to the formation of camphoric anhydride (11) covalently bound to the polymer backbone. While the decomposition of pendant BP groups formed in irradiated films of styrene copolymers with pendant BZ groups leads to crosslinking, only small molecular-weight changes in irradiated MCQ/S were observed. PMID:22509202

Husár, Branislav; Moszner, Norbert; Luká?, Ivan

2012-03-06

25

Zinc phyllosilicates containing amino pendant groups  

International Nuclear Information System (INIS)

[en] Two new zinc silicate hybrids were synthesized via sol-gel process from the reaction of zinc ions with trialkoxyaminesilanes in aqueous basic medium at room temperature and at 373 K. The inorganic-organic hybrids obtained, named SILZn (x=1 or 2) are related to 3-aminopropyl- and N-propylethylenediaminetrimethoxysilane, respectively. From nitrogen content, the number of pendant moles of organic groups in the matrices SILZnx (x=1 to 2) were determined as 5.14 and 3.25 mmol g-1, respectively. The thermogravimetric curves showed mass losses of 50.7% and 58.0% for the same sequence of hybrids, to give the oxides as residue. X-ray diffraction patterns gave basal distances of 2065 and 2814 pm for SILZnx (x=1, 2), with well-formed particles of irregular shapes and sizes, as a characteristic of such material obtained from sol-gel process. The infrared spectra confirmed the attachment of the organic moieties on siloxane groups on the inorganic framework

2004-01-01

26

Synthesis and structural determination of zinc complexes based on an anilido-aldimine ligand containing an O-donor pendant arm: zinc alkoxide derivative as an efficient initiator for ring-opening polymerization of cyclic esters.  

Science.gov (United States)

Zinc complexes bearing the anilido-aldiminate AA(OMe) ligand (AA(OMe)-H = (E)-2,6-diisopropyl-N-(2-(((2-methoxyethyl)imino)methyl)phenyl)aniline) were synthesized in a stepwise method and were structurally characterized. The reaction of AA(OMe)-H (1) with one equivalent of diethyl zinc (ZnEt2) furnishes a three-coordinated and mononuclear zinc complex [(AA(OMe))ZnEt] (2). Further reaction of 2 with a stoichiometric amount of benzyl alcohol (BnOH) affords a four-coordinated and dinuclear zinc benzylalkoxide complex [(AA(OMe))Zn(?-OBn)]2 (3). In the presence of two equivalents of AA(OMe)-H with ZnEt2, a homoleptic and four-coordinated zinc complex [(AA(OMe))2Zn] (4) is formed. The geometry around the zinc centres of 3 and 4 are both distorted tetrahedrals, while 2 adopts a different coordination mode with a slightly distorted trigonal planar geometry. The variable-temperature (1)H NMR studies of 3 illustrate that 3 exhibits a dinuclear structure in solution at low temperature as well as in the solid state. While raising the temperature, it drifts towards dissociation to form a mononuclear zinc benzylalkoxide species, which coexists in solution. The ring-opening polymerizations of ?-caprolactone (?-CL) and ?-butyrolactone (?-BL) catalyzed by complexes 3 and 4 are investigated. The ?-CL and ?-BL polymerizations initiated by zinc alkoxide 3 were demonstrated to have living characteristics and to proceed in a controlled manner with narrow polydispersity indices (PDIs initiator ratio (1200/1) initiated by 3 has also been reported. PMID:23797573

Wang, Chao-Hsiang; Li, Chen-Yu; Huang, Bor-Hunn; Lin, Chu-Chieh; Ko, Bao-Tsan

2013-06-24

27

Synthesis and structural determination of zinc complexes based on an anilido-aldimine ligand containing an O-donor pendant arm: zinc alkoxide derivative as an efficient initiator for ring-opening polymerization of cyclic esters.  

UK PubMed Central (United Kingdom)

Zinc complexes bearing the anilido-aldiminate AA(OMe) ligand (AA(OMe)-H = (E)-2,6-diisopropyl-N-(2-(((2-methoxyethyl)imino)methyl)phenyl)aniline) were synthesized in a stepwise method and were structurally characterized. The reaction of AA(OMe)-H (1) with one equivalent of diethyl zinc (ZnEt2) furnishes a three-coordinated and mononuclear zinc complex [(AA(OMe))ZnEt] (2). Further reaction of 2 with a stoichiometric amount of benzyl alcohol (BnOH) affords a four-coordinated and dinuclear zinc benzylalkoxide complex [(AA(OMe))Zn(?-OBn)]2 (3). In the presence of two equivalents of AA(OMe)-H with ZnEt2, a homoleptic and four-coordinated zinc complex [(AA(OMe))2Zn] (4) is formed. The geometry around the zinc centres of 3 and 4 are both distorted tetrahedrals, while 2 adopts a different coordination mode with a slightly distorted trigonal planar geometry. The variable-temperature (1)H NMR studies of 3 illustrate that 3 exhibits a dinuclear structure in solution at low temperature as well as in the solid state. While raising the temperature, it drifts towards dissociation to form a mononuclear zinc benzylalkoxide species, which coexists in solution. The ring-opening polymerizations of ?-caprolactone (?-CL) and ?-butyrolactone (?-BL) catalyzed by complexes 3 and 4 are investigated. The ?-CL and ?-BL polymerizations initiated by zinc alkoxide 3 were demonstrated to have living characteristics and to proceed in a controlled manner with narrow polydispersity indices (PDIs < 1.12). An efficient catalytic performance for the ?-BL polymerization with a high monomer-to-initiator ratio (1200/1) initiated by 3 has also been reported.

Wang CH; Li CY; Huang BH; Lin CC; Ko BT

2013-08-01

28

Photo- or EB-induced cross-linking reaction of the polymers containing pendant epoxide or vinyl ether groups from glycidyl vinyl ether  

International Nuclear Information System (INIS)

Polymers containing pendant epoxide or vinyl ether groups were synthesized by radical copolymerization of glycidyl vinyl ether (GVE) with N-phenylmaleimide (NPM) and N-phenoxycarbonyloxymaleimide (NPCM), or by ring-opening alternating copolymerization of GVE with phthalic anhydride (PAn). In the photo-induced cross-linking reaction, the pendant vinyl ether groups in poly(GVE-PAn) showed higher reactivity than the pendant epoxide groups in poly(GVE-NPM), and poly(GVE-PAn) was readily cross-linked by various dithiols with or without benzophenone. In the electron beam (EB)-induced cross-linking reaction, the sensitivity of poly(GVE-NPCM), which has pendant epoxide and carbonate groups, was higher than that of poly(GVE-NPM) containing only pendant epoxide groups. Furthermore, the EB-sensitivity of poly(GVE-PAn) was even higher than that of poly(GVE-NPM) or poly(GVE-NPCM). (author).

1991-01-01

29

Photo- or EB-induced cross-linking reaction of the polymers containing pendant epoxide or vinyl ether groups from glycidyl vinyl ether  

Energy Technology Data Exchange (ETDEWEB)

Polymers containing pendant epoxide or vinyl ether groups were synthesized by radical copolymerization of glycidyl vinyl ether (GVE) with N-phenylmaleimide (NPM) and N-phenoxycarbonyloxymaleimide (NPCM), or by ring-opening alternating copolymerization of GVE with phthalic anhydride (PAn). In the photo-induced cross-linking reaction, the pendant vinyl ether groups in poly(GVE-PAn) showed higher reactivity than the pendant epoxide groups in poly(GVE-NPM), and poly(GVE-PAn) was readily cross-linked by various dithiols with or without benzophenone. In the electron beam (EB)-induced cross-linking reaction, the sensitivity of poly(GVE-NPCM), which has pendant epoxide and carbonate groups, was higher than that of poly(GVE-NPM) containing only pendant epoxide groups. Furthermore, the EB-sensitivity of poly(GVE-PAn) was even higher than that of poly(GVE-NPM) or poly(GVE-NPCM). (author).

Sasano, Mikio; Nishikubo, Tadatomi (Kanagawa Univ., Yokohama (Japan). Faculty of Engineering)

1991-08-01

30

Hysteresis in forced oscillations of pendant drops  

International Nuclear Information System (INIS)

[en] A hysteresis phenomenon has been revealed through experiments conducted with large-amplitude forced oscillations of pendant drops in air. Under strong excitation, the frequency response of a drop forced at constant amplitude exhibits jump behavior; a larger peak response amplitude ?? appears at a lower frequency ?? during a downward (?) variation of forcing frequency than during an upward (?) variation, viz. ??>?? and ???. Similar results are obtained when forcing amplitude is varied at constant frequency. This behavior is characteristic of a system with a soft nonlinearity. These findings indicate that oscillating pendant drops constitute a convenient system for studying nonlinear dynamics

1995-01-01

31

Hole-transporting and emitting pendant polymers for organic electroluminescent devices  

Science.gov (United States)

New hole-transporting pendant polymers with high glass-transition temperatures (Tgs) above 200 °C were designed and synthesized. Multilayer organic electroluminescent (EL) devices using the new polymers as the hole-transport layer and quinacridone-doped tris(8-quinolinolato)aluminum as the emitting layer exhibited high performance. One of the hole-transporting polymers functioned well as a hole injection buffer layer in organic EL devices. New green- and orange-emitting pendant polymers with high Tgs and desired ambipolar character were also designed and synthesized. Organic EL devices using these emitting polymers also exhibited good performance. One of the hole-transporting polymer showed a high hole carrier mobility of over 10-3 cm2V-1s-1 at an electric field of 1.0 × 105 Vcm-1, as determined by a time-of-flight method.

Kageyama, Hiroshi; Mutaguchi, Daisuke; Hashimoto, Keisuke; Nagamatsu, Daisuke; Tanaka, Masatake; Okumoto, Kenji; Ohsedo, Yutaka; Shirota, Yasuhiko

2006-12-01

32

55Cobalt complexes with pendant carbohydrates as potential PET imaging agents  

International Nuclear Information System (INIS)

Bis-ligand cobalt(II) complexes of four 3-hydroxy-4-pyridinone ligands with pendant carbohydrates were synthesized and examined for their potential as radiopharmaceuticals. Non-radioactive complexes were prepared on the macroscopic scale and characterized by elemental analysis, mass spectrometry, IR and UV/visible spectroscopy. Facile radiolabeling produced the 55Co complexes in high radiochemical yields (>95%). Identification of the radiolabeled compounds was accomplished by HPLC comparison with the corresponding non-radioactive complexes.

2007-01-01

33

{sup 55}Cobalt complexes with pendant carbohydrates as potential PET imaging agents  

Energy Technology Data Exchange (ETDEWEB)

Bis-ligand cobalt(II) complexes of four 3-hydroxy-4-pyridinone ligands with pendant carbohydrates were synthesized and examined for their potential as radiopharmaceuticals. Non-radioactive complexes were prepared on the macroscopic scale and characterized by elemental analysis, mass spectrometry, IR and UV/visible spectroscopy. Facile radiolabeling produced the {sup 55}Co complexes in high radiochemical yields (>95%). Identification of the radiolabeled compounds was accomplished by HPLC comparison with the corresponding non-radioactive complexes.

Ferreira, Cara L. [TRIUMF, 4004 Wesbrook Mall, Vancouver, BC, V6T 2A3 (Canada); Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC, V6T 1Z1 (Canada); Lapi, Suzanne [TRIUMF, 4004 Wesbrook Mall, Vancouver, BC, V6T 2A3 (Canada); Department of Chemistry, Simon Fraser University, Burnaby, BC, V5A 1S6 (Canada); Steele, Jennifer; Green, David E. [Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC, V6T 1Z1 (Canada); Ruth, Thomas J. [TRIUMF, 4004 Wesbrook Mall, Vancouver, BC, V6T 2A3 (Canada); Adam, Michael J. [TRIUMF, 4004 Wesbrook Mall, Vancouver, BC, V6T 2A3 (Canada)], E-mail: adam@triumf.ca; Orvig, Chris [Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC, V6T 1Z1 (Canada)], E-mail: orvig@chem.ubc.ca

2007-12-15

34

Alkaline Earth metallocenes coordinated with ester pendants: synthesis, structural characterization, and application in metathesis reactions.  

UK PubMed Central (United Kingdom)

A variety of ester-substituted cyclopentadiene derivatives have been synthesized by one-pot reactions of 1,4-dilithio-1,3-butadienes, CO, and acid chlorides. Direct deprotonation of the ester-substituted cyclopentadienes with Ae[N(SiMe3 )2 ]2 (Ae=Ca, Sr, Ba) efficiently generated members of a new class of heavier alkaline earth (Ca, Sr, Ba) metallocenes in good to excellent yields. Single-crystal X-ray structural analysis demonstrated that these heavier alkaline earth metallocenes incorporated two intramolecularly coordinated ester pendants and multiply-substituted cyclopentadienyl ligands. The corresponding transition metal metallocenes, such as ferrocene derivatives and half-sandwich cyclopentadienyl tricarbonylrhenium complexes, could be generated highly efficiently by metathesis reactions. The multiply-substituted cyclopentadiene ligands bearing an ester pendant, and the corresponding heavier alkaline earth and transition-metal metallocenes, may have further applications in coordination chemistry, organometallic chemistry, and organic synthesis.

Li H; Zhang WX; Xi Z

2013-09-01

35

Alkaline Earth metallocenes coordinated with ester pendants: synthesis, structural characterization, and application in metathesis reactions.  

Science.gov (United States)

A variety of ester-substituted cyclopentadiene derivatives have been synthesized by one-pot reactions of 1,4-dilithio-1,3-butadienes, CO, and acid chlorides. Direct deprotonation of the ester-substituted cyclopentadienes with Ae[N(SiMe3 )2 ]2 (Ae=Ca, Sr, Ba) efficiently generated members of a new class of heavier alkaline earth (Ca, Sr, Ba) metallocenes in good to excellent yields. Single-crystal X-ray structural analysis demonstrated that these heavier alkaline earth metallocenes incorporated two intramolecularly coordinated ester pendants and multiply-substituted cyclopentadienyl ligands. The corresponding transition metal metallocenes, such as ferrocene derivatives and half-sandwich cyclopentadienyl tricarbonylrhenium complexes, could be generated highly efficiently by metathesis reactions. The multiply-substituted cyclopentadiene ligands bearing an ester pendant, and the corresponding heavier alkaline earth and transition-metal metallocenes, may have further applications in coordination chemistry, organometallic chemistry, and organic synthesis. PMID:23934787

Li, Heng; Zhang, Wen-Xiong; Xi, Zhenfeng

2013-08-09

36

Oligonorbornenes with hammock-like crown ether pendants as artificial transmembrane ion channel.  

UK PubMed Central (United Kingdom)

Trimeric oligonorbornenes with hammock-like crown ether pendants 3b and 3c were selectively synthesized by cascade metathetical cyclopolymerization upon treatment with the first generation Grubbs catalyst. These crown-ether-containing oligonorbornenes are impregnated in egg yolk phosphatidylcholine (EYPC) liposome as an artificial ion channel. The efficiency of the sodium ion transport properties has been examined. Oligomer 3c having a polar hydroxy end group exhibits the highest transport efficiency, which is comparable with the best efficiencies reported in literature. The orientation of the crown ether moieties in these oligomers may be critical for the ion transport properties.

Lin NT; Xie CY; Huang SL; Chen CH; Luh TY

2013-07-01

37

Conjugated polymer network films of poly(p-phenylene vinylene) with hole-transporting carbazole pendants: dual photoluminescence and electrochromic behavior.  

Science.gov (United States)

A series of poly(p-phenylene vinylene) (PPV) copolymers functionalized with hole-transport and electrochemically active carbazole units as pendant moieties is reported. These polymers exhibit photoluminescence properties by virtue of the PPV analogous backbone. They were also designed as precursor polymer bearing the electroactive carbazole group to form conjugated polymer network (CPN) films by electrodeposition. The electrochemical polymerization of the pendant units eventually lead to a dual property electro-optically active thin film - photoluminescence (PL) behavior that can be attenuated with CPN formation, and a reversible doping and dedoping processes at controlled potentials that lead to an electrochromic behavior. This reveals the ability to incorporate complementary optical and electro-optical properties within the same film using the CPN approach. It should be possible to design and synthesize other PPV ?-conjugated polymers with efficient pendant hole-transport groups exhibiting tunable PL and electrochromism with cross-linking. PMID:22329863

Ponnapati, Ramakrishna; Felipe, Mary Jane; Muthalagu, Vetrichelvan; Puno, Katherine; Wolff, Birte; Advincula, Rigoberto

2012-03-02

38

Conjugated polymer network films of poly(p-phenylene vinylene) with hole-transporting carbazole pendants: dual photoluminescence and electrochromic behavior.  

UK PubMed Central (United Kingdom)

A series of poly(p-phenylene vinylene) (PPV) copolymers functionalized with hole-transport and electrochemically active carbazole units as pendant moieties is reported. These polymers exhibit photoluminescence properties by virtue of the PPV analogous backbone. They were also designed as precursor polymer bearing the electroactive carbazole group to form conjugated polymer network (CPN) films by electrodeposition. The electrochemical polymerization of the pendant units eventually lead to a dual property electro-optically active thin film - photoluminescence (PL) behavior that can be attenuated with CPN formation, and a reversible doping and dedoping processes at controlled potentials that lead to an electrochromic behavior. This reveals the ability to incorporate complementary optical and electro-optical properties within the same film using the CPN approach. It should be possible to design and synthesize other PPV ?-conjugated polymers with efficient pendant hole-transport groups exhibiting tunable PL and electrochromism with cross-linking.

Ponnapati R; Felipe MJ; Muthalagu V; Puno K; Wolff B; Advincula R

2012-03-01

39

Copoly(arlene ether)s containing pendant sulfonic acid groups as proton exchange membrane  

Energy Technology Data Exchange (ETDEWEB)

A copoly(arylene ether) (PAE) with high fluorine content and a copoly(arylene ether nitrile) (PAEN) with high nitrile content, each containing pendant phenyl sulfonic acids were synthesized. The P AE and PAEN were prepared from decafluorobiphenyl (DFBP) and difluorobenzonitrile (DFBN) respectively, by polycondensation with 2-phenylhydroquinone (PHQ) by conventional aromatic nucleophilic substitution reactions. The sulfonic acid groups were introduced by mild post-sulfonation exclusively on the para-position of the pendant phenyl ring in PHQ. The membrane properties of the resulting sulfonated copolymers sP AE and sP AEN were compared for fuel cell applications. The copolymers sPAE and sPAEN, each having a degree of sulfonation (DS) of 1.0 had high ion exchange capacities (IEC{sub v}(wet) (volume-based, wet state)) of 1.77 and 2.55 meq./cm{sup 3}, high proton conductivities of 135.4 and 140.1 mS/cm at 80 C, and acceptable volume-based water uptake of 44.5-51.9 vol% at 80 C, respectively, compared to Nafion. The data points of these copolymer membranes are located in the area of outstanding properties in the trade-off plot of alternative hydrocarbon polyelectrolyte membranes (PEM) for the relationship between proton conductivity versus water uptake (weight based or volume based). Furthermore, the relative selectivity derived from proton conductivity and methanol permeability is higher than that of Nafion.

Kim, Yu Seung [Los Alamos National Laboratory; Kim, Dae Sik [CANADA NRC; Robertson, Gilles [CANADA NRC; Guiver, Michael [CANADA NRC

2008-01-01

40

Novel poly (arylene-ether-ether-ketone)s containing preformed imide unit and pendant long chain alkyl group  

Energy Technology Data Exchange (ETDEWEB)

The studies were carried out to get preformed imide unit containing PEEKs and Co-PEEKs with pendant long chain alkyl group. Thus two new bisphenols; N,N'-bis (4-hydroxy 2-pentadecyl phenyl) pyromellitimide (HPI) (I) and N,N'-bis (4-hydroxy 2-pentadecyl phenyl 3,3',4,4'-benzophenone tetracarboxylic imide (HBI) (II) containing imide unit, pendant C-15 alkyl substituents were synthesized, characterized by spectral data and polycondensed with 4,4'-difluorobenzophenone (DFB) to yield several PEEK and Co-PEEKs. The polymers were characterized by FTIR, inherent viscosity, solubility, and XRD. The polymers were obtained in good yields and had inherent viscosities up to 0.65 dL/g in NMP. Polymerization of mixture of two bisphenols; [(I) and BPA]; and [(II) and BPA] in various mol%, with DFB gave number of the copolymers viz. Co-PEEK-BPAPI and Co-PEEK-BPABI. Many of the Co-PEEKs had good solubility in polar solvents. The solubility of PEEK containing bulky pendant alkyl substituents did not much improve probably due to simultaneous presence of rigid imide structures. XRD analysis indicated that PEEK and Co-PEEKs were partially crystalline or amorphous depending on the nature and % content of imide-bisphenol. These new PEEK materials can be used as high performance films, coatings, gas separation membranes, in aerospace and nuclear industries.

Sayyed, Maheboob M. [Department of Chemistry, Solapur University, Pune-Solapur High Way, Kegaon, Solapur 413 255, Maharashtra (India); Maldar, Noormahmad N., E-mail: maldar_nn@rediffmail.co [Department of Chemistry, Solapur University, Pune-Solapur High Way, Kegaon, Solapur 413 255, Maharashtra (India)

2010-04-15

 
 
 
 
41

Novel poly (arylene-ether-ether-ketone)s containing preformed imide unit and pendant long chain alkyl group  

International Nuclear Information System (INIS)

[en] The studies were carried out to get preformed imide unit containing PEEKs and Co-PEEKs with pendant long chain alkyl group. Thus two new bisphenols; N,N'-bis (4-hydroxy 2-pentadecyl phenyl) pyromellitimide (HPI) (I) and N,N'-bis (4-hydroxy 2-pentadecyl phenyl 3,3',4,4'-benzophenone tetracarboxylic imide (HBI) (II) containing imide unit, pendant C-15 alkyl substituents were synthesized, characterized by spectral data and polycondensed with 4,4'-difluorobenzophenone (DFB) to yield several PEEK and Co-PEEKs. The polymers were characterized by FTIR, inherent viscosity, solubility, and XRD. The polymers were obtained in good yields and had inherent viscosities up to 0.65 dL/g in NMP. Polymerization of mixture of two bisphenols; [(I) and BPA]; and [(II) and BPA] in various mol%, with DFB gave number of the copolymers viz. Co-PEEK-BPAPI and Co-PEEK-BPABI. Many of the Co-PEEKs had good solubility in polar solvents. The solubility of PEEK containing bulky pendant alkyl substituents did not much improve probably due to simultaneous presence of rigid imide structures. XRD analysis indicated that PEEK and Co-PEEKs were partially crystalline or amorphous depending on the nature and % content of imide-bisphenol. These new PEEK materials can be used as high performance films, coatings, gas separation membranes, in aerospace and nuclear industries.

2010-04-15

42

Extended arm polyphenylene dendrimers  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In order to eliminate the de Gennes packing problem, which usually limits the attainable size of dendrimers, a new branching unit containing para-tetraphenylene ethynyl arms has been synthesized and utilized in the preparation of dendrimers of the Müllen type. The divergent principle of synthesis, ...

Andreitchenko, Ekaterina Vladimirovna

43

Tricarbonylrhenium complexes from 2-pyridyl-1,2,3-triazole ligands bearing a 4-substituted phenyl arm: a combined experimental and theoretical study.  

UK PubMed Central (United Kingdom)

Three new pyridyltriazole ligands (named pyta) bearing a 4-substituted phenyl arm (nitro- (2a), chloro- (2b) or aminophenyl (2c) moiety) have been synthesized using a convenient click chemistry strategy. The corresponding tricarbonylrhenium complexes 3a, 3b and 3c were prepared and fully characterized by means of NMR, IR and mass spectrometry, as well as X-ray crystallography for two of them (3a and 3b). The direct connection of a 4-substituted phenyl arm at the N1 position of the triazolyl ring has a significant influence on the geometry of both, the ligands and their corresponding Re-complexes. The dominant structural feature of these complexes concerns the crystal cohesion. Slip-stacked ?-? interactions between two molecules of the complex were observed for 3a and 3b probably resulting from the co-planarity of the organic framework. Furthermore, a combined experimental study and DFT calculations showed that the nature of the pendant arm (X = NO2, NH2 or Cl) could affect the electronic properties of the Re-complexes. If the chloro- or aminophenyl moieties unmodified the photo-physical properties of the complexes 3b and 3c, the presence of a nitrophenyl arm for the complex 3a quenched the luminescence, due to a high probability of non-radiative deactivation.

Wolff M; Munoz L; François A; Carrayon C; Seridi A; Saffon N; Picard C; Machura B; Benoist E

2013-05-01

44

Graft polymerization of substituted styrene polymers having pendant vinylidene groups.  

UK PubMed Central (United Kingdom)

A graft copolymer having a plurality of polymer side chains is disclosed. The starting backbone polymer is a homopolymer or copolymer of a styrene derivative having a pendant vinylidene group on the benzene ring. The graft copolymer may be produced by metallizing said backbone polymer with an alkali metal and then polymerizing an ethylenically unsaturated monomer in the presence of the metallized polymer as an anionic polymerization initiator.

OHATA MASATOSHI; TSUTSUI KOICHI; FUJIMOTO TERUO

45

Maximum Stable Sets and Pendant Vertices in Trees  

CERN Multimedia

One theorem of Nemhauser and Trotter ensures that, under certain conditions, a stable set of a graph G can be enlarged to a maximum stable set of this graph. For example, any stable set consisting of only simplicial vertices is contained in a maximum stable set of G. In this paper we demonstrate that an inverse assertion is true for trees of order greater than one, where, in fact, all the simplicial vertices are pendant. Namely, we show that any maximum stable set of such a tree contains at least one pendant vertex. Moreover, we prove that if T does not own a perfect matching, then a stable set, consisting of at least two pendant vertices, is included in the intersection of all its maximum stable sets. For trees, the above assertion is also a strengthening of one result of Hammer, Hansen, and Simeone, stating that if half of order of G is less than the cardinality of a maximum stable set of G, then the intersection of all its maximum stable sets is non-empty.

Levit, V E; Levit, Vadim E.; Mandrescu, Eugen

1999-01-01

46

Copoly(arylene ether)s containing pendant sulfonic acid groups as proton exchange membranes  

Energy Technology Data Exchange (ETDEWEB)

A copoly(arylene ether) (PAE) with high fluorine content and a copoly(arylene ether nitrile) (PAEN) with high nitrile content, each containing pendant phenyl sulfonic acids were synthesized. The PAE and P AEN were prepared from decafluorobiphenyl (DFBP) and difluorobenzonitrile (DFBN) respectively, by polycondensation with 2phenylhydroquinone (PHQ) by conventional aromatic nucleophilic substitution reactions. sulfonic acid groups were introduced by mild post-sulfonation exclusively on the para-position of the pendant phenyl ring in PHQ. The membrane properties of the resulting sulfonated copolymers sPAE and sPAEN were compared for fuel cell applications. The copolymers sPAE and sPAEN, each having a degree of sulfonation (OS) of 1.0 had high ion exchange capacities (IEC{sub v})(wet) (volume-based, wet state) of 1.77 and 2.55 meq./cm3, high proton conductivities of 135.4 and 140.1 mS/cm at 80 C, and acceptable volume-based water uptake of 44.5 -51.9 vol% at 80 C, respectively, compared to Nafion. The data points of these copolymer membranes are located in the upper left-hand corner in the trade-off plot of alternative hydrocarbon polyelectrolyte membranes (PEM) for the relationship between proton conductivity versus water uptake (weight based or volume based), i.e., high proton conductivity and low water uptake. Furthermore, the relative selectivity derived from proton conductivity and methanol permeability is higher than that of Nafion.

Dae Sik, Kim [Los Alamos National Laboratory; Yu Seung, Kim [Los Alamos National Laboratory; Gilles, Robertson [CANADA-NRC; Guiver, Michael D [CANADA-NRC

2009-01-01

47

ADSORPTION OF CELLOBIOSE-PENDANT POLYMERS TO A CELLULOSE MATRIX DETERMINED BY QUARTZ CRYSTAL MICROBALANCE ANALYSIS  

Directory of Open Access Journals (Sweden)

Full Text Available Cellobiose-pendant polymers were synthesized by radical polymerization and their affinity for a cellulose matrix was investigated by quartz crystal microbalance (QCM). A 2-(methacryloyloxy)ethylureido cellobiose (MOU-Cel) macromer was synthesized by coupling cellobiosylamine with 2-(methacryloyloxy)ethyl isocyanate followed by polymerization in an aqueous radical reaction system. The interaction of the resulting poly(MOU-Cel) with a pure cellulose matrix in water was evaluated by QCM analysis. Poly(MOU-Cel) was strongly adsorbed to the cellulose substrate, whereas neither cellobiose nor MOU-Cel macromer exhibited an attractive interaction with cellulose. This specific interaction was not inhibited by the presence of ionic contaminants, suggesting that multiple cellobiopyranose moieties in each polymer molecule might cooperatively enhance its affinity for cellulose. Moderate insertion of acrylamide units into the polymer backbone improved the affinity for cellulose, possibly due to an increased mobility of sugar side chains. Polymers such as these, with a high affinity for cellulose, have potential applications for the surface functionalization of cellulose-based materials, including paper products.

Shingo Yokota; Takefumi Ohta; Takuya Kitaoka; Hiroyuki Wariishi

2009-01-01

48

Design guides for offshore structures Anchors and pendants  

Energy Technology Data Exchange (ETDEWEB)

Conception, realization and utilization of anchoring systems for offshore floating support are examined in this practical guide. Generally choice and sizing of anchors arise from calculation based, for a large part, on know how. Safety improvement and cost reduction require both a more rational way which is the aim of this book written for engineers, especially for offshore petroleum exploration and development. Basic information on stress from environment on offshore structures, calculation of stress on pendants, kinetics and behavior of the main types of anchors, recommendations for choice, size, operation, testing and monitoring anchoring systems are examined.

1987-01-01

49

Jérusalem et la Palestine pendant la première guerre mondiale  

Directory of Open Access Journals (Sweden)

Full Text Available La journée d’études « Jérusalem et la Palestine pendant la première guerre mondiale » s’inscrit dans le cadre du programme « La France, l’Europe occidentale et la Palestine, 1799-1948 » du Centre de recherche français de Jérusalem. À la suite du colloque portant sur un long XIXe siècle, de 1799 à 1917 (9-11 novembre 1998), et avant la rencontre des 29-30 novembre-1er décembre 1999, portant sur la période mandataire (1917-1948), il paraissait indispensable de s’attarder sur le premier conflit ...

Dominique Trimbur

2008-01-01

50

Robotic arm  

Energy Technology Data Exchange (ETDEWEB)

A robotic arm positionable within a nuclear vessel by access through a small diameter opening and having a mounting tube supported within the vessel and mounting a plurality of arm sections for movement lengthwise of the mounting tube as well as for movement out of a window provided in the wall of the mounting tube is disclosed. An end effector, such as a grinding head or welding element, at an operating end of the robotic arm, can be located and operated within the nuclear vessel through movement derived from six different axes of motion provided by mounting and drive connections between arm sections of the robotic arm. The movements are achieved by operation of remotely-controllable servo motors, all of which are mounted at a control end of the robotic arm to be outside the nuclear vessel. 23 figs.

Kwech, H.

1989-04-18

51

Robotic arm  

Energy Technology Data Exchange (ETDEWEB)

A robotic arm positionable within a nuclear vessel by access through a small diameter opening and having a mounting tube supported within the vessel and mounting a plurality of arm sections for movement lengthwise of the mounting tube as well as for movement out of a window provided in the wall of the mounting tube. An end effector, such as a grinding head or welding element, at an operating end of the robotic arm, can be located and operated within the nuclear vessel through movement derived from six different axes of motion provided by mounting and drive connections between arm sections of the robotic arm. The movements are achieved by operation of remotely-controllable servo motors, all of which are mounted at a control end of the robotic arm to be outside the nuclear vessel.

Kwech, Horst (Lake Bluff, IL)

1989-04-18

52

Remarkable structure effects on chiroptical properties of polyisocyanides carrying proline pendants.  

UK PubMed Central (United Kingdom)

Chiral polymers with simple chemical structures and high helical conformation stabilities are important for their applications as chiral supports and asymmetrical catalysts. We report herein the synthesis of a series of aliphatic polyisocyanides carrying proline pendants of different chiralities, and an investigation of the effects of the chemical structures of these pendants on the chiroptical properties of the polymers. The configuration of the chiral center at the 4-position of the proline pendants was changed from S to R to check its effect on the handedness of the helical conformation. To examine the effects of steric hindrance on the stabilities of the helical conformation for these aliphatic representatives, proline pendants with various substituents at both the carboxyl and amine terminals were designed. To further examine the steric effects of the proline pendants, aromatic counterparts were also prepared. In the latter case, the effects of hydrogen bonds between pendant units on the enhancement and stabilities of the helical conformation were investigated by switching from the ester to an amide linkage. The Cotton effects and signal intensities of both aliphatic and aromatic polyisocyanides from circular dichroism spectroscopy were compared based on the bulkiness of the pendant groups, solvent polarities, and solution temperatures. It was found that highly stable helical conformations of polyisocyanides could be imposed by small bulky monoproline pendants.

Xu A; Hu G; Hu Y; Zhang X; Liu K; Kuang G; Zhang A

2013-09-01

53

Waveform synthesizer  

Energy Technology Data Exchange (ETDEWEB)

A method of producing optical and electrical pulses of desired shape. An optical pulse of arbitrary but defined shape illuminates one end of an array of optical fiber waveguides of differing lengths to time differentiate the input pulse. The optical outputs at the other end of the array are combined to form a synthesized pulse of desired shape.

Franks, Larry A. (Santa Barbara, CA); Nelson, Melvin A. (Santa Barbara, CA)

1981-01-01

54

Holding arm  

UK PubMed Central (United Kingdom)

An accumulating mechanism is provided for use in conjunction with a shear mechanism used in forestry applications. A tree harvesting apparatus employs a shear mechanism to cut the trees, a grapple mechanism to hold the trees while they are being cut, and an accumulator mechanism to accumulate several trees before depositing a load thereof. The accumulator mechanism of the present invention comprises an elongated base portion having a forward edge thereof aligned with a rear edge of the shear blade as well as the rear edge of the grapple mechanism. Pivotally mounted on the base portion of the accumulator mechanism is a holding arm which is pivoted forwardly to grasp cut trees and hold them in place as the harvesting machine moves from place to place to cut subsequent trees. The holding arm has a curved inner surface and is engageable with a forward projection of the accumulator base to retain trees in the space provided therebetween. The outer surface of the holding arm is concentric with the pivot axis of the accumulator mechanism to readily enable the holding arm to be extracted from between a newly cut tree and the group of trees already accumulated. The arm is then closed to encompass both the newly cut tree and the trees already accumulated. A hydraulic cylinder is disposed between the base of the accumulator mechanism and the holding arm to extend and retract the holding arm during the accumulation process.

KIELB EUGENE JAMES

55

Synthesis and Characterization of Novel Soluble Aromatic Polyesters with Pendant Cyano Groups  

Directory of Open Access Journals (Sweden)

Full Text Available 2, 6-Bis (4-carboxyphenoxy) benzonitrile was first synthesized by condensation of 2, 6-difluorobenzonitrile with p-Hydroxybenzoic acid in the presence of KOH and DMSO. And then the reaction of 2, 6-bis (4-carboxyphenoxy) benzonitrile with sulfur oxychloride yieded 2, 6-bis (4-chloroformylphenoxy) benzonitrile (BClPOBN). A series of novel soluble aromatic polyesters with pendant cyano groups were prepared by polycondensation of different aromatic diphenols and 2,6-bis (4-chloroformylphenoxy) benzonitrile (BClPOBN) using 1,2-dichoroethane (DCE) as solvent and pyridine as the absorbent of HCl. The resulting polymers were characterized by different physico-chemical techniques, such as FT-IR, Thermogravimetric analysis (TGA), Wide angle X-ray diffraction (WAXD), and so on. All the polymers had the proposed structure and were amorphous. Thermogravimetric studies showed that the thermal decomposition temperatures (Tds) at 5% weight loss of polymers were 391~406 ? in N2 atmosphere, indicating they had good thermal stabilities. The prepared polyesters exhibited good solubility in some common solvents, such as CHCl3, ethylene dichloride (DCE), CH2Cl2, tetrahydrofuran (THF) as well as aprotic polar organic solvents such as N-methyl pyrrolidone (NMP), N, N-dimethylacetamide (DMAC) and N, N-dimethylformamide (DMF), and so on.

Yikai Yu; Mingzhong Cai; Tao Wang

2009-01-01

56

Brushed block copolymer micelles with pH-sensitive pendant groups for controlled drug delivery.  

UK PubMed Central (United Kingdom)

PURPOSE: To investigate the effects of small aliphatic pendent groups conjugated through an acid-sensitive linker to the core of brushed block copolymer micelles on particle properties. METHODS: The brushed block copolymers were synthesized by conjugating five types of 2-alkanone (2-butanone, 2-hexanone, 2-octanone, 2-decanone, and 2-dodecanone) through an acid-labile hydrazone linker to poly(ethylene glycol)-poly(aspartate hydrazide) block copolymers. RESULTS: Only block copolymers with 2-hexanone and 2-octanone (PEG-HEX and PEG-OCT) formed micelles with a clinically relevant size (< 50 nm in diameter), low critical micelle concentration (CMC, < 20 ?M), and drug entrapment yields (approximately 5 wt.%). Both micelles degraded in aqueous solutions in a pH-dependent manner, while the degradation was accelerated in an acidic condition (pH 5.0) in comparison to pH 7.4. Despite these similar properties, PEG-OCT micelles controlled the entrapment and pH-dependent release of a hydrophobic drug most efficiently, without altering particle size, shape, and stability. The molecular weight of PEG (12 kDa vs 5 kDa) induced no change in pH-controlled drug release rates of PEG-OCT micelles. CONCLUSION: Acid-labile small aliphatic pendant groups are useful to control the entrapment and release of a hydrophobic drug physically entrapped in the core of brushed block copolymer micelles.

Lee HJ; Bae Y

2013-08-01

57

Aliphatic Polymers Bearing Pendant Radical Groups as Charge Carrying Moieties in Organic Electronic Applications  

Science.gov (United States)

The implementation of highly conjugated polymers has led to an explosion of high-performance organic electronic devices; however, many important synthetic, physical, and mechanical properties of these macromolecules still lag behind polymers with non-conjugated backbones. In order to implement the positive aspects of both macromolecular classes, we have synthesized radical polymers (i.e., where a pendant stable radical group is present on each repeat unit of the polymer) using controlled polymerization mechanisms. We demonstrate that these next-generation conducting polymers have thermal and physical properties similar to that of aliphatic polymers while still retaining charge transport properties akin to those of well-studied conjugated polymer systems. Specifically, we characterize the charge transport ability of radical polymers using a model radical polymer, poly(2,2,6,6-tetramethylpiperidinyloxymethacrylate), and propose a mechanism for charge transport in these molecules. Furthermore, because of the low optical absorption in the visible spectrum associated with non-conjugated polymers, radical polymers are utilized as anodic modifiers in organic photovoltaic devices and show promise in being more stable to environmental conditions than traditional anode-modifying materials.

Boudouris, Bryan; Rostro, Lizbeth; Baradwaj, Aditya

2013-03-01

58

Design of novel ?-carboline derivatives with pendant 5-bromothienyl and their evaluation as phosphodiesterase-5 inhibitors.  

Science.gov (United States)

New derivatives with the tetrahydro-?-carboline-imidazolidinedione and tetrahydro-?-carboline-piperazinedione scaffolds and a pendant bromothienyl moiety at C-5/C-6 were synthesized and tested for their ability to inhibit PDE5 in vitro. The following SAR can be concluded: The tetracyclic scaffold is essential for PDE5 inhibition; the ethyl group is the most suitable among the adopted N-substituents on the terminal ring (hydantoin/piperazinedione); the appropriate stereochemistry of C-5/C-6 derived from the aldehyde rather than C-11a/C-12a derived from tryptophan appears crucial for inhibition of PDE5; surprisingly, derivatives with the hydantoin terminal ring are more active than their analogs with the piperazinedione ring; the selectivity versus PDE5 relative to PDE11 with cGMP as a substrate is mainly a function of the substitution and stereochemistry pattern of the external ring, in other words of the interaction with the H-loop residues of the isozymes. Thirteen derivatives showed PDE5 inhibitory activity with IC(50) values in the range of 0.16-5.4?µm. Compound 8 was the most potent PDE5 inhibitor and showed selectivity towards PDE5 versus other PDEs, with a selectivity index of 49 towards PDE5 rather than PDE11 with cGMP as the substrate. PMID:23307609

El-Gamil, Dalia S; Ahmed, Nermin S; Gary, Bernard D; Piazza, Gary A; Engel, Matthias; Hartmann, Rolf W; Abadi, Ashraf H

2013-01-01

59

Design of novel ?-carboline derivatives with pendant 5-bromothienyl and their evaluation as phosphodiesterase-5 inhibitors.  

UK PubMed Central (United Kingdom)

New derivatives with the tetrahydro-?-carboline-imidazolidinedione and tetrahydro-?-carboline-piperazinedione scaffolds and a pendant bromothienyl moiety at C-5/C-6 were synthesized and tested for their ability to inhibit PDE5 in vitro. The following SAR can be concluded: The tetracyclic scaffold is essential for PDE5 inhibition; the ethyl group is the most suitable among the adopted N-substituents on the terminal ring (hydantoin/piperazinedione); the appropriate stereochemistry of C-5/C-6 derived from the aldehyde rather than C-11a/C-12a derived from tryptophan appears crucial for inhibition of PDE5; surprisingly, derivatives with the hydantoin terminal ring are more active than their analogs with the piperazinedione ring; the selectivity versus PDE5 relative to PDE11 with cGMP as a substrate is mainly a function of the substitution and stereochemistry pattern of the external ring, in other words of the interaction with the H-loop residues of the isozymes. Thirteen derivatives showed PDE5 inhibitory activity with IC(50) values in the range of 0.16-5.4?µm. Compound 8 was the most potent PDE5 inhibitor and showed selectivity towards PDE5 versus other PDEs, with a selectivity index of 49 towards PDE5 rather than PDE11 with cGMP as the substrate.

El-Gamil DS; Ahmed NS; Gary BD; Piazza GA; Engel M; Hartmann RW; Abadi AH

2013-01-01

60

On the Odd Gracefulness of Cyclic Snakes With Pendant Edges  

Directory of Open Access Journals (Sweden)

Full Text Available Graceful and odd gracefulness of a graph are two entirely different concepts. A graph may posses one orboth of these or neither. We present four new families of odd graceful graphs. In particular we show an oddgraceful labeling of the linear kC4 ? snake e mK1 and therefore we introduce the odd graceful labeling of4 1 kC ? snake e mK ( for the general case ). We prove that the subdivision of linear 3 kC ? snake is oddgraceful. We also prove that the subdivision of linear 3 kC ? snake with m-pendant edges is odd graceful.Finally, we present an odd graceful labeling of the crown graph n 1 P e mK .

E. M. Badr

2013-01-01

 
 
 
 
61

ROBOTIC ARM  

UK PubMed Central (United Kingdom)

A robotic arm (10) is provided, for example for inspecting a rotary machine such as a gas turbine engine. The arm has a plurality of groups of links (20) having articulations (24) therebetween for movement in a first plane, the groups having articulations (26) with respect to each other for movement in a second orthogonal plane. Thus the arm can move around objects such as aerofoils in the engine, and also move up or down to remain close to the rotary surface of the machine.

BUCKINGHAM ROBERT OLIVER; GRAHAM ANDREW CRISPIN

62

Arm CT scan  

Science.gov (United States)

CAT scan - arm; Computed axial tomography scan - arm; Computed tomography scan - arm; CT scan - arm ... stopping.) A computer creates separate images of the arm area, called slices. These images can be stored, ...

63

Biological Evaluation of Polymeric Controlled Activity Herbicide Systems Containing Pendant Metribuzin.  

Science.gov (United States)

The rate at which an herbicide is released from a polymer matrix is critical to the biological effectiveness of a controlled activity system. Nine such systems containing pendant metribuzin were evaluated as to release rates in aqueous and edaphic environ...

K. E. Savage C. L. McCormick B. H. Hutchinson

1978-01-01

64

Removal and recovery of toxic metal ions from aqueous waste sites using polymer pendant ligands  

International Nuclear Information System (INIS)

[en] The purpose of this project is to investigate the use of polymer pendant ligand technology to remove and recover toxic metal ions from DOE aqueous waste sites. Polymer pendant lgiands are organic ligands, anchored to crosslinked, modified divinylbenzene-polystyrene beads, that can selectively complex metal ions. The metal ion removal step usually occurs through a complexation or ion exchange phenomena, thus recovery of the metal ions and reuse of the beads is readily accomplished

1996-01-01

65

Removal and recovery of toxic metal ions from aqueous waste sites using polymer pendant ligands  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this project is to investigate the use of polymer pendant ligand technology to remove and recover toxic metal ions from DOE aqueous waste sites. Polymer pendant lgiands are organic ligands, anchored to crosslinked, modified divinylbenzene-polystyrene beads, that can selectively complex metal ions. The metal ion removal step usually occurs through a complexation or ion exchange phenomena, thus recovery of the metal ions and reuse of the beads is readily accomplished.

Fish, D. [Lawrence Berkeley National Lab., CA (United States)

1996-10-01

66

Effects of Arm Number and Arm Length on Thermal Properties of Linear and Star-shaped Poly(D,L-lactide)s  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Influences of arm number and arm length of poly(D,L-lactide)s (PDLLs) on their thermal properties were investigated. The PDLLs with linear (1 arm) and star (4, 6 and 16 arms) shapes were synthesized via ring-opening polymerization of DLL monomer in bulk at 130°C for 24 h under nitrogen atmosphere. S...

Mangkorn Srisa-ard; Yodthong Baimark

67

Distinct features of organosilyl-grafted pendant groups attached in the RUB-18 interlayer space.  

Science.gov (United States)

Two distinct methods to graft the silylating agent 3-cyanopropyltriclorosilane (CN) in the interlayer space of the layered silicate Na-RUB-18, with composition Na2Si8O17.nH2O, are described. The organosilylation was carried out by reflux and solvent evaporation methodologies, using the intercalated surfactant cetyltrimethylammonium after sodium exchange as one intermediate (CTA-RUB-18) and the acidic form (H-RUB-18) as the other intermediate. The resulting silylated derivatives obtained by both methods possessed basal spacings of 1.19 and 1.54 nm, and 1.26 and 1.16 nm, starting from CTA-RUB-18 and H-RUB-18, with the reflux and solvent evaporation methods, respectively. A favourable condition for this immobilization methodology is the use of small amounts of the silylating agent, with six times less than the previous procedure. The maximum amount of the silane attached to the RUB-18 surface, based on analytical results considering the nitrogen content, gave the values 5.64, 4.16, 4.37 and 4.05 mmol g(-1), respectively. All preparation processes were followed by elemental analyses and X-ray diffraction and the organofunctionalizations were confirmed through chemical and thermogravimetric data. The presence of pendant chains covalently bonded to the inorganic RUB-18 layers was confirmed by 13C and 29Si NMR spectroscopy. The inorganic-organic hybrids have the ability for divalent cation removal from aqueous solutions at the solid/liquid interface. The series of adsorption isotherms were favourably adjusted to the Freundlich equation, demonstrating the applicability of these synthesized chemically modified layered materials. PMID:19727461

Macedo, Thaís R; Airoldi, Claudio

2009-07-17

68

Distinct features of organosilyl-grafted pendant groups attached in the RUB-18 interlayer space.  

UK PubMed Central (United Kingdom)

Two distinct methods to graft the silylating agent 3-cyanopropyltriclorosilane (CN) in the interlayer space of the layered silicate Na-RUB-18, with composition Na2Si8O17.nH2O, are described. The organosilylation was carried out by reflux and solvent evaporation methodologies, using the intercalated surfactant cetyltrimethylammonium after sodium exchange as one intermediate (CTA-RUB-18) and the acidic form (H-RUB-18) as the other intermediate. The resulting silylated derivatives obtained by both methods possessed basal spacings of 1.19 and 1.54 nm, and 1.26 and 1.16 nm, starting from CTA-RUB-18 and H-RUB-18, with the reflux and solvent evaporation methods, respectively. A favourable condition for this immobilization methodology is the use of small amounts of the silylating agent, with six times less than the previous procedure. The maximum amount of the silane attached to the RUB-18 surface, based on analytical results considering the nitrogen content, gave the values 5.64, 4.16, 4.37 and 4.05 mmol g(-1), respectively. All preparation processes were followed by elemental analyses and X-ray diffraction and the organofunctionalizations were confirmed through chemical and thermogravimetric data. The presence of pendant chains covalently bonded to the inorganic RUB-18 layers was confirmed by 13C and 29Si NMR spectroscopy. The inorganic-organic hybrids have the ability for divalent cation removal from aqueous solutions at the solid/liquid interface. The series of adsorption isotherms were favourably adjusted to the Freundlich equation, demonstrating the applicability of these synthesized chemically modified layered materials.

Macedo TR; Airoldi C

2009-09-01

69

Quantifying nisin adsorption behavior at pendant PEO layers.  

UK PubMed Central (United Kingdom)

The antimicrobial peptide nisin shows potent activity against Gram-positive bacteria including the most prevalent implant-associated pathogens. Its mechanism of action minimizes the opportunity for the rise of resistant bacteria and it does not appear to be toxic to humans, suggesting good potential for its use in antibacterial coatings for selected medical devices. A more quantitative understanding of nisin loading and release from polyethylene oxide (PEO) brush layers will inform new strategies for drug storage and delivery, and in this work optical waveguide lightmode spectroscopy was used to record changes in adsorbed mass during cyclic adsorption-elution experiments with nisin, at uncoated and PEO-coated surfaces. PEO layers were prepared by radiolytic grafting of Pluronic® surfactant F108 or F68 to silanized silica surfaces, producing long- or short-chain PEO layers, respectively. Kinetic patterns were interpreted with reference to a model accounting for history-dependent adsorption, in order to evaluate rate constants for nisin adsorption and desorption, as well as the effect of pendant PEO on the lateral clustering behavior of nisin. Nisin adsorption was observed at the uncoated and F108-coated surfaces, but not at the F68-coated surfaces. Nisin showed greater resistance to elution by peptide-free buffer at the uncoated surface, and lateral rearrangement and clustering of adsorbed nisin was apparent only at the uncoated surface. We conclude peptide entrapment at the F108-coated surface is governed by a hydrophobic inner region of the PEO brush layer that is not sufficient for nisin entrapment in the case of the shorter PEO chains of the F68-coated surface.

Dill JK; Auxier JA; Schilke KF; McGuire J

2013-04-01

70

Quantifying nisin adsorption behavior at pendant PEO layers.  

Science.gov (United States)

The antimicrobial peptide nisin shows potent activity against Gram-positive bacteria including the most prevalent implant-associated pathogens. Its mechanism of action minimizes the opportunity for the rise of resistant bacteria and it does not appear to be toxic to humans, suggesting good potential for its use in antibacterial coatings for selected medical devices. A more quantitative understanding of nisin loading and release from polyethylene oxide (PEO) brush layers will inform new strategies for drug storage and delivery, and in this work optical waveguide lightmode spectroscopy was used to record changes in adsorbed mass during cyclic adsorption-elution experiments with nisin, at uncoated and PEO-coated surfaces. PEO layers were prepared by radiolytic grafting of Pluronic® surfactant F108 or F68 to silanized silica surfaces, producing long- or short-chain PEO layers, respectively. Kinetic patterns were interpreted with reference to a model accounting for history-dependent adsorption, in order to evaluate rate constants for nisin adsorption and desorption, as well as the effect of pendant PEO on the lateral clustering behavior of nisin. Nisin adsorption was observed at the uncoated and F108-coated surfaces, but not at the F68-coated surfaces. Nisin showed greater resistance to elution by peptide-free buffer at the uncoated surface, and lateral rearrangement and clustering of adsorbed nisin was apparent only at the uncoated surface. We conclude peptide entrapment at the F108-coated surface is governed by a hydrophobic inner region of the PEO brush layer that is not sufficient for nisin entrapment in the case of the shorter PEO chains of the F68-coated surface. PMID:23445762

Dill, Justen K; Auxier, Julie A; Schilke, Karl F; McGuire, Joseph

2013-01-17

71

Les trotskystes grecs pendant la seconde guerre Mondiale  

Directory of Open Access Journals (Sweden)

Full Text Available Comment les deux courants du trotskysme grec, pourchassés dès les années 30, ont-ils réagi face à l'occupation de leur pays et à la résistance d'obédience communiste ?Les trotskystes en Grèce étaient divisés, malgré des discussions d’unification dans les camps de Metaxas. Ils refusèrent de soutenir la Grèce contre l’intervention italo-allemande en 1940-1941 et s’opposèrent aux illusions dans les démocraties alliées. Fin 1942 ils reprirent une activité clandestine, refusant de se joindre à la Résistance mais aussi de choisir un côté militaire dans les affrontements avec l’occupant et ses supplétifs. En octobre 1944, les trotskystes s'agitèrent contre les Britanniques pendant que l’EAM les laissait entrer dans Athènes. Le KKE exécuta des dizaines de trotskystes. Ceux-ci restèrent neutres dans la guerre civile de décembre 1944. Leur sectarisme contribua à les stériliser lorsque, après les accords de Varkiza en février 1945, la direction du KKE était vulnérable aux accusations qu’elle avait conduit la révolution à la défaite.Trotskyists in Greece were divided, despite unification discussions in Metaxas’ concentration camps. They refused to support Greece against the 1940-41 Italo-German intervention and opposed illusions in Allied democracies. At the end of 1942 they resumed underground activity, refusing to join the Resistance but also to take a military side in the fighting against the occupiers and their local proxy forces. In October 1944 the Trotskyists agitated against the British while the EAM let them into Athens. The KKE executed dozens of Trotskyists. The Trotskyists remained neutral in the December 1944 civil war. Their sectarianism contributed to sterilize them when, after the February 1945 Varkiza Agreement, the KKE leadership was vulnerable to accusations of having led the revolution to defeat.

Alexis Hen

2011-01-01

72

Robotic Arm  

Science.gov (United States)

A robotic arm that can be worn at home may someday help stroke victims regain lost mobility. It's being developed by Arizona State University bioengineer Jiping He and his colleagues, with support from the National Institutes of Health. The sleeve-like device features four pneumatic muscles, from the shoulder to the wrist, that help the real arm move. As the patient gets stronger over time, the robotic muscles gradually back off.The device is still in the prototype stage, but if it proves successful, it could be a lot cheaper than long-term, one-on-one physical therapy.This resource also includes a text description of the research and links for further inquiry.

American Association for the Advancement of Science (;)

2005-06-27

73

Telescope arm  

Energy Technology Data Exchange (ETDEWEB)

With the telescope arm consisting of several elements which can be moved against one another, measuring- and control-devices can be moved into the space between pressure vessel and wall. The telscope elements are driven by a convex metallic tape which is fixed at the telescope front element and conducted by rolls at the other telescope elements. The steel tape is wrapped upon a coil.

Seifert, W.

1980-02-28

74

Controlled Synthesis of Fluorinated Copolymers with Pendant Sulfonates  

DEFF Research Database (Denmark)

Novel fluorinated copolymers of different architectures and bearing sulfopropyl groups were synthesized by atom transfer radical polymerization (ATRP) of aromatic fluorinated monomers and two modification reactions performed on the polymer chain - demethylation followed by sulfopropylation. As a result two types of fluorinated copolymers were obtained. The first one was synthesized by ATRP of2,3,5,6-tetraflouro4- methoxystyrene (TFMS). Copolymers with different amounts of randomly distributed along the backbone sulfopropyl groups were obtained after the chemical modifications mentioned above. The second type copolymers have diblock architecture with one.of the blocks being sulfopropyl~ed. They were synthesized via ATRP of 2,3,4,5,6pentafluorostyrene (FS) initiated by PTFMS-macroinitiator followed by demethylation and sulfopropylation performed on the TFMS-block (Scheme 1). The) copolymers were characterized by size-exclusion chromatography, FTIR and IH NMR spectroscopy. Their thermal properties were investigated by differential scanning calorimetry and thermal gravimetric analyses.

Dimitrov, Ivaylo; Jankova Atanasova, Katja

2008-01-01

75

Pendant unit effect on electron tunneling in U-shaped molecules  

International Nuclear Information System (INIS)

The electron transfer reactions of three U-shaped donor-bridge-acceptor molecules with different pendant groups have been studied in different solvents as a function of temperature. Analysis of the electron transfer kinetics in nonpolar and weakly polar solvents provides experimental reaction Gibbs energies that are used to parameterize a molecular solvation model. This solvation model is then used to predict energetic parameters in the electron transfer rate constant expression and allow the electronic coupling between the electron donor and electron acceptor groups to be determined from the rate data. The U-shaped molecules differ by alkylation of the aromatic pendant group, which lies in the 'line-of-sight' between the donor and acceptor groups. The findings show that the electronic coupling through the pendant group is similar for these molecules.

2006-05-09

76

Synthesis and photooxidation of styrene copolymer bearing camphorquinone pendant groups  

Digital Repository Infrastructure Vision for European Research (DRIVER)

(±)-10-Methacryloyloxycamphorquinone (MCQ) was synthesized from (±)-10-camphorsulfonic acid either by a known seven-step synthetic route or by a novel, shorter five-step synthetic route. MCQ was copolymerized with styrene (S) and the photochemical behavior of the copolymer MCQ/S was compared with th...

Husár, Branislav; Moszner, Norbert; Luká?, Ivan

77

Synthesis and photooxidation of styrene copolymer bearing camphorquinone pendant groups  

Digital Repository Infrastructure Vision for European Research (DRIVER)

(±)-10-Methacryloyloxycamphorquinone (MCQ) was synthesized from (±)-10-camphorsulfonic acid either by a known seven-step synthetic route or by a novel, shorter five-step synthetic route. MCQ was copolymerized with styrene (S) and the photochemical behavior of the copol...

Branislav Husár; Norbert Moszner; Ivan Luká?

78

Model studies of methyl CoM reductase: methane formation via CH3-S bond cleavage of Ni(I) tetraazacyclic complexes having intramolecular methyl sulfide pendants.  

Science.gov (United States)

The Ni(I) tetraazacycles [Ni(dmmtc)](+) and [Ni(mtc)](+), which have methylthioethyl pendants, were synthesized as models of the reduced state of the active site of methyl coenzyme M reductase (MCR), and their structures and redox properties were elucidated (dmmtc, 1,8-dimethyl-4,11-bis{(2-methylthio)ethyl}-1,4,8,11-tetraaza-1,4,8,11-cyclotetradecane; mtc, 1,8-{bis(2-methylthio)ethyl}-1,4,8,11-tetraaza-1,4,8,11-cyclotetradecane). The intramolecular CH(3)-S bond of the thioether pendant of [Ni(I)(dmmtc)](OTf) was cleaved in THF at 75 °C in the presence of the bulky thiol DmpSH, which acts as a proton source, and methane was formed in 31% yield and a Ni(II) thiolate complex was concomitantly obtained (Dmp = 2,6-dimesityphenyl). The CH(3)-S bond cleavage of [Ni(I)(mtc)](+) also proceeded similarly, but under milder conditions probably due to the lower potential of the [Ni(I)(mtc)](+) complex. These results indicate that the robust CH(3)-S bond can be homolytically cleaved by the Ni(I) center when they are properly arranged, which highlights the significance of the F430 Ni environment in the active site of the MCR protein. PMID:22439643

Nishigaki, Jun-ichi; Matsumoto, Tsuyoshi; Tatsumi, Kazuyuki

2012-03-22

79

Model studies of methyl CoM reductase: methane formation via CH3-S bond cleavage of Ni(I) tetraazacyclic complexes having intramolecular methyl sulfide pendants.  

UK PubMed Central (United Kingdom)

The Ni(I) tetraazacycles [Ni(dmmtc)](+) and [Ni(mtc)](+), which have methylthioethyl pendants, were synthesized as models of the reduced state of the active site of methyl coenzyme M reductase (MCR), and their structures and redox properties were elucidated (dmmtc, 1,8-dimethyl-4,11-bis{(2-methylthio)ethyl}-1,4,8,11-tetraaza-1,4,8,11-cyclotetradecane; mtc, 1,8-{bis(2-methylthio)ethyl}-1,4,8,11-tetraaza-1,4,8,11-cyclotetradecane). The intramolecular CH(3)-S bond of the thioether pendant of [Ni(I)(dmmtc)](OTf) was cleaved in THF at 75 °C in the presence of the bulky thiol DmpSH, which acts as a proton source, and methane was formed in 31% yield and a Ni(II) thiolate complex was concomitantly obtained (Dmp = 2,6-dimesityphenyl). The CH(3)-S bond cleavage of [Ni(I)(mtc)](+) also proceeded similarly, but under milder conditions probably due to the lower potential of the [Ni(I)(mtc)](+) complex. These results indicate that the robust CH(3)-S bond can be homolytically cleaved by the Ni(I) center when they are properly arranged, which highlights the significance of the F430 Ni environment in the active site of the MCR protein.

Nishigaki J; Matsumoto T; Tatsumi K

2012-05-01

80

Hand and Arm Conditions  

Science.gov (United States)

... Public & Patients > Hand and Arm Conditions Hand and Arm Conditions Page Content If you know the name ... below. Otherwise click on an area of the arm below to learn more about common hand conditions. ...

 
 
 
 
81

Chromium(III) catalysed ethylene tetramerization promoted by bis(phosphino)amines with an N-functionalized pendant.  

Science.gov (United States)

Several N-functionalized bis(phosphino)amine ligands with ether, thioether and pyridyl tethers [(R'')2PN(R')P(R'')2=PNP] () have been synthesized. They react with CrCl3(THF)3 in CH2Cl2 to give dinuclear chloro bridged Cr2(micro-Cl)2Cl4(PNP)2 () which converts to the corresponding mononuclear solvento complexes fac-CrCl3(PNP)(NCR) (). The structures of the ligand with R'=-(CH2)3SCH3 and R''=Ph, and the complexes with R=CH3 () and C2H5 (), R'=-(CH2)3SCH3 and R''=Ph) have been established by single-crystal X-ray crystallography. All ligands are active towards ethylene tetramerization in the presence of Cr(III) and excess MAO at 80 degrees C in toluene. The ligand with thioether pendant Et2PN(CH2CH2CH2SCH3)PEt2 () shows the highest selectivity (55% weight in liquid product distribution) towards 1-octene. Complexes and are active towards ethylene polymerization under thermal conditions. PMID:17680038

Weng, Zhiqiang; Teo, Shihui; Andy Hor, T S

2007-05-23

82

Conjugated polymers containing pendant terpyridine complexes as photoactive sensors  

Energy Technology Data Exchange (ETDEWEB)

The authors have synthesized a novel conjugated polymer containing terpyridine receptors. This conjugated, polymer-based fluorescent chemosensory system exhibits unusually high sensitivity toward transition metal ions ({approximately}10{sup {minus}9} M). The fluorescence quenching response of the terpyridine containing conjugated polymer to transition metal ions is related to a facile energy migration in which energy from absorption of a photon, can migrate through the conjugated polymer system and be quenched by trapping sites. Terpyridine receptors can readily bind to transition metal ions and create a low lying Metal to Ligand Transfer (MLCT) state which can act as an excitation trap.

Jiang, B.; Sahay, S.; Jones, W.E. Jr.

1998-07-01

83

The influence of pendant hydroxyl groups on enzymatic degradation and drug delivery of amphiphilic poly[glycidol-block-(epsilon-caprolactone)] copolymers.  

Science.gov (United States)

An amphiphilic diblock copolymer PG-b-PCL with well-controlled structure and pendant hydroxyl groups along hydrophilic block was synthesized by sequential anionic ring-opening polymerization. The micellization and drug release of PG-b-PCL copolymers using pyrene as a fluorescence probe were investigated for determining the influences of copolymer composition and lipase concentration on drug loading capacity and controlled release behavior. The biodegradation of PG-b-PCL copolymers was studied with microspheres as research samples. It has been concluded that the polar hydroxyl groups along each repeat unit of hydrophilic PG block in PG-b-PCL copolymer have great influences on drug encapsulation, drug release, and enzymatic degradation of micelles and microspheres. PMID:19634151

Mao, Jing; Gan, Zhihua

2009-11-10

84

The influence of pendant hydroxyl groups on enzymatic degradation and drug delivery of amphiphilic poly[glycidol-block-(epsilon-caprolactone)] copolymers.  

UK PubMed Central (United Kingdom)

An amphiphilic diblock copolymer PG-b-PCL with well-controlled structure and pendant hydroxyl groups along hydrophilic block was synthesized by sequential anionic ring-opening polymerization. The micellization and drug release of PG-b-PCL copolymers using pyrene as a fluorescence probe were investigated for determining the influences of copolymer composition and lipase concentration on drug loading capacity and controlled release behavior. The biodegradation of PG-b-PCL copolymers was studied with microspheres as research samples. It has been concluded that the polar hydroxyl groups along each repeat unit of hydrophilic PG block in PG-b-PCL copolymer have great influences on drug encapsulation, drug release, and enzymatic degradation of micelles and microspheres.

Mao J; Gan Z

2009-11-01

85

Syntheses of 8-quinolinolatocobalt(III) complexes containing cyclen based auxiliary ligands as models for hypoxia-activated prodrugs.  

Science.gov (United States)

New ligands H(2)L2-H(2)L6 comprise the cyclen macrocycle which is N,N'-dialkylated at the 1,7-nitrogen atoms by three- and four-carbon alkyl chains bearing terminal sulfonic (C(3) H(2)L2), phosphonic (C(3) H(2)L3, C(4) H(2)L4) or carboxylic acid (C(3) H(2)L5, C(4) H(2)L6) groups, and HL7 is N-monoalkylated by a four-carbon sulfonic acid group. The ligands were prepared by alkylation of a bridged bisaminal intermediate. The syntheses of cobalt(III) complexes containing a tetradentate cyclen, N,N'-1,7-Me(2)cyclen, cyclam or L2-L7 ligand together with the bidentate 8-quinolinato (8QO(-)) ligand, of interest as it is a model for a more potent cytotoxic analogue, were investigated. Coordination of ligands (L) cyclen, N,N'-1,7-Me(2)cyclen or cyclam to cobalt(III) was achieved using Na(3)[Co(NO(6))] to form [Co(L)(NO(2))(2)](+). HOTf (trifluoromethansulfonic acid) was used to prepare the triflato complexes [Co(L)(OTf)(2)](+), followed by substitution of the labile triflato ligands to yield [Co(L)(8QO)](ClO(4))(2) isolated as the perchlorate salts. One further example containing cyclam and the 5-hydroxymethyl-8-quinolinato ligand was also prepared by this method. Complexes containing the pendant arm ligands L2-L6 were prepared from the cobalt precursor trans-[Co(py)(4)Cl(2)](+). Reaction of this complex with H(2)L2·4HCl and 8QOH produced [Co(L2)(8QO)] in one step and contains two deprotonated sulfonato pendant arms. The reaction of H(2)L3·4HBr with [Co(py)(4)Cl(2)](+) gave [Co(L3)]Cl in which L3 acts as a hexadenate ligand with the three-carbon phosphonato side chains coordinated to cobalt. H(2)L5·4HCl bearing three-carbon carboxylic acid pendant arms gave a similar result. The four-carbon ligands were coordinated to cobalt by reaction of [Co(py)(4)Cl(2)](+) with H(2)L4·4HBr or H(2)L6·4HCl to give [Co(HL4)Cl(2)] or [Co(H(2)L6)Cl(2)]Cl, which in turn with 8QOH gave the 8QO(-) complexes [Co(L4)(8QO)] bearing anionic phosphate pendant arms or [Co(H(2)L6)(8QO)]Cl(2) containing neutral carboxylic acid side chains. The reaction of Na(3)[Co(CO(3))(3)] with the mono-N-alkylated ligand HL7·4HCl and then HOTf gave [Co(L7)(CO(3))] and then in turn [Co(L7)(OTf)(2)]. The carbonato complex [Co(L7)(CO(3))] with [8QO](2)[SO(4)] produced [Co(L7)(CO(3))]. All complexes containing L7 bear an anionic sulfonato group on the side chain. The synthesis and characterisation of the six new ligands based on N-alkylated cylen ligand and the cobalt complexes outlined above are described, along with cyclic voltammograms of the 8QO(-) complexes and the molecular structures determined by X-ray crystallography of [Co(cyclen)(H(2)O)(2)](OTf)(3) (formed by aquation of the triflato complex), [Co(cyclen)(8QO)](ClO(4))(2), Co(L2)(8QO)·2H(2)O, Co(L4)(8QO)·6H(2)O and [Co(H(2)L6)Cl(2)]Cl·H(2)O. These demonstrate the coordination of the cyclen ligand in the folded anti-O,syn-N configuration with the N-alkylated nitrogens occupying apical positions. PMID:21103540

Chang, John Yu-Chih; Stevenson, Ralph J; Lu, Guo-Liang; Brothers, Penelope J; Clark, George R; Denny, William A; Ware, David C

2010-11-22

86

Syntheses of 8-quinolinolatocobalt(III) complexes containing cyclen based auxiliary ligands as models for hypoxia-activated prodrugs.  

UK PubMed Central (United Kingdom)

New ligands H(2)L2-H(2)L6 comprise the cyclen macrocycle which is N,N'-dialkylated at the 1,7-nitrogen atoms by three- and four-carbon alkyl chains bearing terminal sulfonic (C(3) H(2)L2), phosphonic (C(3) H(2)L3, C(4) H(2)L4) or carboxylic acid (C(3) H(2)L5, C(4) H(2)L6) groups, and HL7 is N-monoalkylated by a four-carbon sulfonic acid group. The ligands were prepared by alkylation of a bridged bisaminal intermediate. The syntheses of cobalt(III) complexes containing a tetradentate cyclen, N,N'-1,7-Me(2)cyclen, cyclam or L2-L7 ligand together with the bidentate 8-quinolinato (8QO(-)) ligand, of interest as it is a model for a more potent cytotoxic analogue, were investigated. Coordination of ligands (L) cyclen, N,N'-1,7-Me(2)cyclen or cyclam to cobalt(III) was achieved using Na(3)[Co(NO(6))] to form [Co(L)(NO(2))(2)](+). HOTf (trifluoromethansulfonic acid) was used to prepare the triflato complexes [Co(L)(OTf)(2)](+), followed by substitution of the labile triflato ligands to yield [Co(L)(8QO)](ClO(4))(2) isolated as the perchlorate salts. One further example containing cyclam and the 5-hydroxymethyl-8-quinolinato ligand was also prepared by this method. Complexes containing the pendant arm ligands L2-L6 were prepared from the cobalt precursor trans-[Co(py)(4)Cl(2)](+). Reaction of this complex with H(2)L2·4HCl and 8QOH produced [Co(L2)(8QO)] in one step and contains two deprotonated sulfonato pendant arms. The reaction of H(2)L3·4HBr with [Co(py)(4)Cl(2)](+) gave [Co(L3)]Cl in which L3 acts as a hexadenate ligand with the three-carbon phosphonato side chains coordinated to cobalt. H(2)L5·4HCl bearing three-carbon carboxylic acid pendant arms gave a similar result. The four-carbon ligands were coordinated to cobalt by reaction of [Co(py)(4)Cl(2)](+) with H(2)L4·4HBr or H(2)L6·4HCl to give [Co(HL4)Cl(2)] or [Co(H(2)L6)Cl(2)]Cl, which in turn with 8QOH gave the 8QO(-) complexes [Co(L4)(8QO)] bearing anionic phosphate pendant arms or [Co(H(2)L6)(8QO)]Cl(2) containing neutral carboxylic acid side chains. The reaction of Na(3)[Co(CO(3))(3)] with the mono-N-alkylated ligand HL7·4HCl and then HOTf gave [Co(L7)(CO(3))] and then in turn [Co(L7)(OTf)(2)]. The carbonato complex [Co(L7)(CO(3))] with [8QO](2)[SO(4)] produced [Co(L7)(CO(3))]. All complexes containing L7 bear an anionic sulfonato group on the side chain. The synthesis and characterisation of the six new ligands based on N-alkylated cylen ligand and the cobalt complexes outlined above are described, along with cyclic voltammograms of the 8QO(-) complexes and the molecular structures determined by X-ray crystallography of [Co(cyclen)(H(2)O)(2)](OTf)(3) (formed by aquation of the triflato complex), [Co(cyclen)(8QO)](ClO(4))(2), Co(L2)(8QO)·2H(2)O, Co(L4)(8QO)·6H(2)O and [Co(H(2)L6)Cl(2)]Cl·H(2)O. These demonstrate the coordination of the cyclen ligand in the folded anti-O,syn-N configuration with the N-alkylated nitrogens occupying apical positions.

Chang JY; Stevenson RJ; Lu GL; Brothers PJ; Clark GR; Denny WA; Ware DC

2010-12-01

87

STRETCHER WITH EXPANDABLE ARMS  

UK PubMed Central (United Kingdom)

The invention relates to a stretcher with expandable arms especially meant for the transport of the ill or injured persons in narrow spaces. According to the invention, the stretcher with expandable arms comprises two tubular cross-arms (1) having a fix handle (5) fastened by screwing at each end, and wherein two pairs of independent expandable arms (6) slide by using some friction members (12), at the end of each expandable arm (6) there being a mobile handle (8), the expandable arms (6) being locked at the required lenghth by means of some chucks (9) pressing some profiled jaws (10) in some circular grooves (7) cut in the expandable arms (6), while, in order to prevent the expandable arms (6) from getting out of the tubular cross-arms (1), a safety ring (11) is mounted at each inner end of the expandable arms (6).

IOTOV COSTEL

88

Strong-Arm Tactics  

Science.gov (United States)

Why do we care about a robotic arm? What does a robotic arm have to do with engineering? Creating such an arm comes from a design that involves mechanical, electrical, and computer science engineers. As expected, students generally do not know the complexity that goes into building and programming a robotic arm. This activity allows students to control a robotic arm from both a machineâs and a computer science engineerâs perspective by performing a simple task with a few instructions and constraints.

Integrated Teaching And Learning Program

89

Cobalt(II) complexes with aromatic carboxylates and N-functionalized cyclam bearing 2-pyridylmethyl pendant arms  

Directory of Open Access Journals (Sweden)

Full Text Available Novel binuclear Co(II) complexeswithN-functionalized cyclam, N,N’,N”,N’’’-tetrakis(2-pyridylmethyl)tetraazacyclotetradecane (tpmc) and one of the aromatic monoor dicarboxylato ligands (benzoate, phthalate or isophthalate ions) were prepared. They were analyzed and studied by elemental analyses (C, H, N), electrical conductivities, VIS and IR spectroscopy andmagnetic as well as cyclic voltammetric measurements. In [Co2(C6H5COO)2tpmc](ClO4)2.3H2O, the benzoate ligands are most probably coordinated as chelates in the trans-position to each Co(II) and the macrocycle adopts a chair conformation. In the complexes [Co2(Y)tpmc](ClO4)2·zH2O, (Y = phthalate or i-phthalate dianizon, z = 2; 4), it is proposed that the isomeric dicarboxylates are bonded combined as bridges and chelates. The composition and the assumed geometries of the complexes are compared with the, earlier reported, corresponding Cu(II) complexes. Cyclic voltammetry measurements showed that the compounds are electrochemically stable.

G. VUCKOVIC; V. STANIC; S. P. SOVILJ; M. ANTONIJEVIC-NIKOLIC; J. MROZINSKI

2005-01-01

90

Reaction of Lanthanum(III) and Gadolinium(III) complexes coordinated by pendant-armed macrocyclic ligand with salicylaldehyde  

International Nuclear Information System (INIS)

In the reaction of Lanthanum(III) and Gadolinium(III) complexes coordinated by the ligand 1,9-bis(2-aminoethyl)-1, 4, 6, 9, 12, 14-hexaazacyclohexadecane with salicylaldehyde, only Gd3+ was led to an unexpected complex with the ligand tris{2-(salicylideneamino)ethyl}amine. The difference of the reactivity was applied to the separation of La3+ and Gd3+. (author).

1994-01-01

91

Arms control and the arms race  

Energy Technology Data Exchange (ETDEWEB)

A collection of 16 articles from the Scientific American discusses the evolution of nuclear weapons since 1945 and the attempts to control the nuclear arms race through national action and international negotiations. The articles and commentaries by political scientists Bruce M. Russett and Fred Chernoff combine technical information on weapons and deployment systems with political analysis of current arms strategies and diplomacy. The articles are grouped under three major topics: SALT and the history of arms control negotiations, current strategic arms negotiations, and European security. A separate abstract was written for each of the 16 articles selected for the Energy Data Base. 226 references.

1985-01-01

92

Biologically active dinuclear complexes of cobalt(II) with a pendant octaazamacrocyclic ligand and pseudohalides  

Directory of Open Access Journals (Sweden)

Full Text Available In the three newly-prepared mixed dinuclear penta-coordinated cobalt(II) complexes, with the pendant macrocyclic ligand N,N',N'',N'''-tetrakis(2-pyridylmethyl)-1,4,8,11-tetraazacyclotetradecane (tpmc) and pseudohalides, of the general formula SCo2(NCY)ntpmcC(ClO4)4-n(Y = O, n = 1; Y = S, Se, n = 2), the NCO- group is bridging, and the other two pseudohalides are nonbridging, i.e., singly coordinated to each metal in the trans position. It can be supposed that the pendant ligand assumes the boat conformation, in complex involving the cyanate ligand whereas it is in the chair conformation in the complexes involving the thiocyanate and selenocyanate ligands. It was found that these complexes exhibit biological activity towards the following strains of microorganisms: Esherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923), Bacillus thuringiensis (ssp. kurstaki), Pseudomonas aeruginosa (ATCC 27853) and Candida albicans.

GORDANA N. VUCKOVIC; MAJA T. SUMAR; ILIJA D. BRCESKI; VUKADIN M. LEOVAC; DRAGANA S. MITIC

1999-01-01

93

Latticelike smectic liquid crystal phase in a rigid-rod helical polyisocyanide with mesogenic pendants.  

Science.gov (United States)

We report a unique macromolecule consisting of a rodlike helical polyisocyanide backbone with a narrow molecular weight distribution and rigid mesogenic chiral pendants linked via a flexible spacer that exhibits lyotropic nematic and latticelike new smectic (lat-Sm) liquid crystal phases at different concentrations. The unprecedented lat-Sm phase is associated with the smectic ordering of both the stiff polymer backbone and the rigid-rod side groups. A detailed investigation of the films using X-ray scattering and atomic force microscopy revealed a novel tilted smectic layer structure of the polymer backbone aligned perpendicular to the smectic layer of the mesogenic pendants, which arrange in an antiparallel overlapping interdigitated manner. PMID:21627115

Kajitani, Takashi; Onouchi, Hisanari; Sakurai, Shin-ichiro; Nagai, Kanji; Okoshi, Kento; Onitsuka, Kiyotaka; Yashima, Eiji

2011-05-31

94

Rocker Arm: - A Review  

Directory of Open Access Journals (Sweden)

Full Text Available Over the years rocker arms have been optimized in its design and material for better performance. Durability, toughness, high dimension stability, wear resistance, strength and cost of materials as well as economic factors are the reasons for optimization of rocker arm. This paper reviews the various types of rocker arms, based on published sources from the last 40 years in order to understand rocker arm for its problem identification and further optimization. This paper present what rocker arm is, where it is used and why it is used, History related to rocker arm and it working is described. Various types of rocker arm used in vehicles and different materials used for making rocker arm are studied in this paper. Reasons for Failure of rocker arm are also discussed in this paper.

SYED MUJAHID HUSAIN; PROF.SIRAJ SHEIKH

2013-01-01

95

Roller arm centralizer  

Energy Technology Data Exchange (ETDEWEB)

A roller arm centralizer to center a drill string in a well pipe. The arms of the roller arm centralizer include shoulders to limit movement of the arms in the direction of the centralizer body which prevents the arms from being locked in a straight line adjacent to the centralizer body. The shoulders also prevent the arms from being forced into a undesired configuration; wherein one arm is parallel to the body and the other two arms form a ''V'', by an abrupt decrease in the bore diameter. The roller arm centralizer remains operative when passing through relatively narrow sections of well pipe or through well pipe having abrupt changes in diameter.

Kinley, K. S.; Pratt, A. R.

1985-12-10

96

Sensing system for detection and control of deposition on pendant tubes in recovery and power boilers  

Energy Technology Data Exchange (ETDEWEB)

A system for detection and control of deposition on pendant tubes in recovery and power boilers includes one or more deposit monitoring sensors operating in infrared regions of about 4 or 8.7 microns and directly producing images of the interior of the boiler, or producing feeding signals to a data processing system for information to enable a distributed control system by which the boilers are operated to operate said boilers more efficiently. The data processing system includes an image pre-processing circuit in which a 2-D image formed by the video data input is captured, and includes a low pass filter for performing noise filtering of said video input. It also includes an image compensation system for array compensation to correct for pixel variation and dead cells, etc., and for correcting geometric distortion. An image segmentation module receives a cleaned image from the image pre-processing circuit for separating the image of the recovery boiler interior into background, pendant tubes, and deposition. It also accomplishes thresholding/clustering on gray scale/texture and makes morphological transforms to smooth regions, and identifies regions by connected components. An image-understanding unit receives a segmented image sent from the image segmentation module and matches derived regions to a 3-D model of said boiler. It derives a 3-D structure the deposition on pendant tubes in the boiler and provides the information about deposits to the plant distributed control system for more efficient operation of the plant pendant tube cleaning and operating systems.

Kychakoff, George (Maple Valley, WA); Afromowitz, Martin A. (Mercer Island, WA); Hogle, Richard E. (Olympia, WA)

2008-10-14

97

Protonation of Ferrous Dinitrogen Complexes Containing a Diphosphine Ligand with a Pendant Amine  

Energy Technology Data Exchange (ETDEWEB)

The addition of protons to pendant amine containing ferrous dinitrogen complexes, of the type [FeX(N2)(PEtNMePEt)(dmpm)]+ (X = H, Cl, or Br; PEtNMePEt = Et2PCH2N(Me)CH2PEt2 and dmpm = Me2PCH2PMe2), was found to protonate at the pendant amine as opposed to the dinitrogen ligand. This protonation increased the ?N2 of the complex by about 25 cm-1, shifting the Fe(II/I) couple 330 mV to a more positive potential. A similar shift was observed in the case of [FeX(CO)(PEtNMePEt)(dmpm)]+ (X = H, Cl, or Br). Computational analysis verified these experimental results and showed the coordination of N2 to Fe(II) centers increases the basicity of N2 (vs. free N2) by 13 and 20 pKa units for the trans halides and hydrides, respectively. Although the iron center was found to increase the basicity of the bound N2 ligand, coordinated N2 is not sufficiently basic to be protonated. In the case of ferrous dinitrogen complexes containing a basic pendant methylamine, the amine site was determined to be the most basic site by 30 pKa units compared to protonation at the N2 ligand. To increase the basicity of the N2 ligand in order to promote proton transfer from the pendant amine to the N2 ligand, chemical reduction of these ferrous dinitrogen complexes was performed and found to result in oxidative addition of the methylene C-H bond of the PEtNMePEt ligand to Fe, preventing isolation of a reduced Fe(0) N2 complex. This work was supported as part of the Center for Molecular Electrocatalysis, an Energy Frontier Research Center funded by the U.S. Department of Energy Office of Science, Office of Basic Energy Sciences.

Heiden, Zachariah M.; Chen, Shentan; Mock, Michael T.; Dougherty, William G.; Kassel, W. S.; Rousseau, Roger J.; Bullock, R. Morris

2013-04-01

98

Quantitative X-ray fluorescence analysis of an Egyptian faience pendant and comparison with PIXE.  

Science.gov (United States)

The X-ray fluorescence (XRF) technique is a common choice in the archaeometric field for in situ investigations with portable instruments. This work shows that XRF portable systems can be used for quantitative analyses using appropriate software, obtaining a similar accuracy to that provided with other techniques such as particle-induced X-ray emission (PIXE), as shown for an Egyptian faience pendant and for two glass standards. PMID:19636540

de Viguerie, L; Duran, A; Bouquillon, A; Solé, V A; Castaing, J; Walter, P

2009-12-01

99

Quantitative X-ray fluorescence analysis of an Egyptian faience pendant and comparison with PIXE.  

UK PubMed Central (United Kingdom)

The X-ray fluorescence (XRF) technique is a common choice in the archaeometric field for in situ investigations with portable instruments. This work shows that XRF portable systems can be used for quantitative analyses using appropriate software, obtaining a similar accuracy to that provided with other techniques such as particle-induced X-ray emission (PIXE), as shown for an Egyptian faience pendant and for two glass standards.

de Viguerie L; Duran A; Bouquillon A; Solé VA; Castaing J; Walter P

2009-12-01

100

Use of the pendant drop method to measure interfacial tension between molten polymers  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper the pendant drop method to measure interfacial tension between molten polymers is reviewed. A typical pendant drop apparatus is presented. The algorithms used to infer interfacial tension from the geometrical profile of the pendant drop are described in details, in particular a new routine to evaluate correctly the value of the radius at the apex of the drop, necessary to the calculation of interfacial tension is presented. The method was evaluated for the possibility of measuring the interfacial tension between polyethylene and polystyrene. It is shown that the method is unsuitable for the measurement of interfacial tension between high density polyethylene and polystyrene due possibly to a too small difference of density between the two polymers. Values of interfacial tension between low density polyethylene (LDPE) and polystyrene (PS) as a function of the molecular weight of PS are presented. It was shown that the interfacial tension between LDPE and PS increased as a function of molecular weight of PS up to values of molecular weight of roughly 40,000 g/mol, value for which entanglements occur.

Emerson Y. Arashiro; Nicole R. Demarquette

1999-01-01

 
 
 
 
101

Synthetic transformations of a pendant nitrile moiety in group 4 metallocene complexes.  

Science.gov (United States)

Functional group transformations at the group 4 metallocene framework have been demonstrated, which have provided relatively straightforward access to otherwise synthetically challenging derivatives. The pendant nitrile group in Ti and Zr metallocene complexes of the type [(?(5)-C5Me5)(?(5)-C5H4CMe2CH2CN)MCl2] was converted into an intramolecularly bound ketimido moiety by alkylation, which took place not only at the nitrile, but also at the metal centre. The choice of an alkylating reagent (alkyl/aryl lithium, Grignard reagent) was crucial: e.g., 2 equiv. of MeMgBr effected the alkylation only at the metal, yielding selectively complexes [(?(5)-C5Me5)(?(5)-C5H4CMe2CH2CN)MMe2], while the use of PhMgBr, PhLi, or MeLi instead gave selectively the ketimido complexes. Organyl lithium reagents were, however, not compatible with the titanocene derivatives. The metal-bound ketimides were subsequently cleaved off by the reaction with HCl, which afforded metallocene dichlorides with a pendant imino group. These compounds were easily protonated again at the nitrogen atom to produce a cationic iminium moiety. Aqueous hydrolysis of the imine or its respective hydrochloride proved to be viable in the case of Zr and it finally afforded a pendant ketone group attached to the zirconocene framework. PMID:23536005

Pinkas, Ji?í; Císa?ová, Ivana; Kubišta, Ji?í; Horá?ek, Michal; Lama?, Martin

2013-05-21

102

Synthetic transformations of a pendant nitrile moiety in group 4 metallocene complexes.  

UK PubMed Central (United Kingdom)

Functional group transformations at the group 4 metallocene framework have been demonstrated, which have provided relatively straightforward access to otherwise synthetically challenging derivatives. The pendant nitrile group in Ti and Zr metallocene complexes of the type [(?(5)-C5Me5)(?(5)-C5H4CMe2CH2CN)MCl2] was converted into an intramolecularly bound ketimido moiety by alkylation, which took place not only at the nitrile, but also at the metal centre. The choice of an alkylating reagent (alkyl/aryl lithium, Grignard reagent) was crucial: e.g., 2 equiv. of MeMgBr effected the alkylation only at the metal, yielding selectively complexes [(?(5)-C5Me5)(?(5)-C5H4CMe2CH2CN)MMe2], while the use of PhMgBr, PhLi, or MeLi instead gave selectively the ketimido complexes. Organyl lithium reagents were, however, not compatible with the titanocene derivatives. The metal-bound ketimides were subsequently cleaved off by the reaction with HCl, which afforded metallocene dichlorides with a pendant imino group. These compounds were easily protonated again at the nitrogen atom to produce a cationic iminium moiety. Aqueous hydrolysis of the imine or its respective hydrochloride proved to be viable in the case of Zr and it finally afforded a pendant ketone group attached to the zirconocene framework.

Pinkas J; Císa?ová I; Kubišta J; Horá?ek M; Lama? M

2013-05-01

103

Design and Engineering of a Chess-Robotic Arm  

CERN Multimedia

In the scope of the "Chess-Bot" project, this study's goal is to choose the right model for the robotic arm that the "the Chess-Bot" will use to move the pawn from a cell to another. In this paper, there is the definition and the structure of a robot arm. Also, the different engineering and kinematics fundamentals of the robot and its components will be detailed. Furthermore, the different structures of robotic arms will be presented and compared based on different criteria. Finally, a model for "the Chess-Bot" arm will be synthesized based on accurate algorithms and equations.

Elouafiq, Ali

2012-01-01

104

An Improved Controller Arm for a Remotely Related Slave Arm.  

Science.gov (United States)

A segmented controller arm, configured and dimensioned to form a miniature kinematic replica of a remotely related slave arm is outlined. The arm includes a plurality of joints for affording segments of the arm simultaneous angular displacement, a plurali...

J. K. Salisbury

1977-01-01

105

Controlled Radical Polymerization and Quantification of Solid State Electrical Conductivities of Macromolecules Bearing Pendant Stable Radical Groups.  

UK PubMed Central (United Kingdom)

Macromolecules with aliphatic backbones that bear pendant stable radical groups (i.e., radical polymers) have attracted much attention in applications where a supporting electrolyte is capable of aiding charge transport in solution; however, the utilization of these materials in solid state applications has been limited. Here, we synthesize a model radical polymer, poly(2,2,6,6-tetramethylpiperidinyloxy methacrylate) (PTMA), through a controlled reversible addition-fragmentation chain transfer (RAFT) mediated polymerization mechanism to generate well-defined and easily-tunable functional polymers. These completely amorphous, electronically-active polymers demonstrate relatively high glass transition temperatures (Tg ~170 °C) and, due to the aliphatic nature of the backbone of the radical polymers, are almost completely transparent in the visible region of the electromagnetic spectrum. Additionally, we quantify the conductivity of PTMA (~10(-6) S cm(-1)) and find it to be on par with pristine ?-conjugated polymers such as poly(phenylene vinylenes) (PPVs) and poly(3-alkylthiophenes) (P3ATs). Furthermore, we demonstrate that the addition of small molecules bearing stable radical groups provides for more solid state charge hopping sites without altering the chemical nature of radical polymers; this, in turn, allows for an increase in the conductivity of PTMA relative to neat PTMA thin films while still retaining the same high degree of optical transparency and device stability. Because of the synthetic flexibility and easily-controlled doping mechanisms (that do not alter the PTMA chemistry), radical polymers present themselves as promising and tunable materials for transparent solid state plastic electronic applications.

Rostro L; Baradwaj AG; Boudouris BW

2013-09-01

106

Arm Injuries and Disorders  

Science.gov (United States)

... your body, 3 of them are in your arm; the humerus, radius and ulna. Your arms are also made up of muscles, joints, tendons ... Injuries to any of these parts of the arm can occur during sports, a fall or an ...

107

The arms race control  

International Nuclear Information System (INIS)

[en] Written in 1961, this paper presents the content of a book entitled 'The arms race control' where the author outlined the difference between disarmament and arms control, described the economic and moral role of arms race, the importance of force balance for international security. He wandered whether arms control could ensure this balance and whether nuclear balance meant force balance. Force balance then appears to be a precarious and unsteady component of international security. He commented the challenges of disarmament, recalled some arguments for a nuclear disarmament. Then he discussed what would be an arms control with or without disarmament (either nuclear or conventional)

2010-01-01

108

Lightweight rocker arm  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a lightweight rocker arm assembly of the cam follows type for an internal combustion engine. It comprises: an elongated rocker arm body formed of a metal matrix composite material, the rocker arm body having a generally rectangular centralized opening extending between sidewalls thereof, a first end formed to engage a support upon which the rocker arm pivots and a second end for engaging and activating a valve stem; and cam engaging means comprising a roller formed of a first ceramic material for engaging a cam on a rotating cam shaft to pivot the rocker arm assembly, the roller being mounted for rotation on a roller shaft formed of a second ceramic material and mounted in circular openings in the sidewalls of the rocker arm body intermediate the rocker arm body first and second ends.

Allor, R.L.; Herman, J.A. Sr.; DeBell, G.C.

1991-02-26

109

Novel nanostructure amino acid-based poly(amide-imide)s enclosing benzimidazole pendant group in green medium: fabrication and characterization.  

Science.gov (United States)

In the present work, several novel optically active nanostructure poly(amide-imide)s (PAI)s were synthesized via step-growth polymerization reaction of chiral diacids based on pyromellitic dianhydride-derived dicarboxylic acids containing different natural amino acids such as L-alanine, S-valine, L-leucine, L-isoleucine, L-methionine, and L-phenylalanine with 2-(3,5-diaminophenyl)-benzimidazole under green conditions using molten tetrabutylammonium bromide. The new optically active PAIs were achieved in good yields and moderate inherent viscosity up to 0.41 dL/g. The synthesized polymers were characterized with FT-IR, (1)H-NMR, X-ray diffraction, field emission scanning electron microscopy (FE-SEM), elemental and thermogravimetric analysis (TGA) techniques. These polymers show high solubility in organic polar solvents due to the presence of amino acid and benzimidazole pendant group at room temperature. FE-SEM results show that, these chiral nanostructured PAIs have spherical shapes and the particle size is around 20-80 nm. On the basis of TGA data, such PAIs are thermally stable and can be classified as self-extinguishing polymers. In addition due to the existence of amino acids in the polymer backbones, these macromolecules are not only optically active but also could be biodegradable and thus may well be classified under environmentally friendly materials. PMID:22327513

Mallakpour, Shadpour; Dinari, Mohammad

2012-02-11

110

Novel nanostructure amino acid-based poly(amide-imide)s enclosing benzimidazole pendant group in green medium: fabrication and characterization.  

UK PubMed Central (United Kingdom)

In the present work, several novel optically active nanostructure poly(amide-imide)s (PAI)s were synthesized via step-growth polymerization reaction of chiral diacids based on pyromellitic dianhydride-derived dicarboxylic acids containing different natural amino acids such as L-alanine, S-valine, L-leucine, L-isoleucine, L-methionine, and L-phenylalanine with 2-(3,5-diaminophenyl)-benzimidazole under green conditions using molten tetrabutylammonium bromide. The new optically active PAIs were achieved in good yields and moderate inherent viscosity up to 0.41 dL/g. The synthesized polymers were characterized with FT-IR, (1)H-NMR, X-ray diffraction, field emission scanning electron microscopy (FE-SEM), elemental and thermogravimetric analysis (TGA) techniques. These polymers show high solubility in organic polar solvents due to the presence of amino acid and benzimidazole pendant group at room temperature. FE-SEM results show that, these chiral nanostructured PAIs have spherical shapes and the particle size is around 20-80 nm. On the basis of TGA data, such PAIs are thermally stable and can be classified as self-extinguishing polymers. In addition due to the existence of amino acids in the polymer backbones, these macromolecules are not only optically active but also could be biodegradable and thus may well be classified under environmentally friendly materials.

Mallakpour S; Dinari M

2012-10-01

111

Inorganic syntheses, v.38  

CERN Multimedia

The volumes in this continuing series provide a compilation of current techniques and ideas in inorganic synthetic chemistry. Includes inorganic polymer syntheses and preparation of important inorganic solids, syntheses used in the development of pharmacologically active inorganic compounds, small-molecule coordination complexes, and related compounds. Also contains valuable information on transition organometallic compounds including species with metal-metal cluster molecules. All syntheses presented here have been tested.

Shriver, Duward F

2009-01-01

112

Inorganic syntheses, v.48  

CERN Multimedia

The volumes in this continuing series provide a compilation of current techniques and ideas in inorganic synthetic chemistry. Includes inorganic polymer syntheses and preparation of important inorganic solids, syntheses used in the development of pharmacologically active inorganic compounds, small-molecule coordination complexes, and related compounds. Also contains valuable information on transition organometallic compounds including species with metal-metal cluster molecules. All syntheses presented here have been tested.

Shreeve, Jean'ne M

2009-01-01

113

Inorganic syntheses, v.50  

CERN Multimedia

The volumes in this continuing series provide a compilation of current techniques and ideas in inorganic synthetic chemistry. Includes inorganic polymer syntheses and preparation of important inorganic solids, syntheses used in the development of pharmacologically active inorganic compounds, small-molecule coordination complexes, and related compounds. Also contains valuable information on transition organometallic compounds including species with metal-metal cluster molecules. All syntheses presented here have been tested.

Allcock, Harry R

2009-01-01

114

Inorganic syntheses, v.58  

CERN Document Server

The volumes in this continuing series provide a compilation of current techniques and ideas in inorganic synthetic chemistry. Includes inorganic polymer syntheses and preparation of important inorganic solids, syntheses used in the development of pharmacologically active inorganic compounds, small-molecule coordination complexes, and related compounds. Also contains valuable information on transition organometallic compounds including species with metal-metal cluster molecules. All syntheses presented here have been tested.

Grimes, Russell N

2009-01-01

115

Inorganic syntheses, v.52  

CERN Document Server

The volumes in this continuing series provide a compilation of current techniques and ideas in inorganic synthetic chemistry. Includes inorganic polymer syntheses and preparation of important inorganic solids, syntheses used in the development of pharmacologically active inorganic compounds, small-molecule coordination complexes, and related compounds. Also contains valuable information on transition organometallic compounds including species with metal-metal cluster molecules. All syntheses presented here have been tested.

Kaesz, Herbert D

2009-01-01

116

Inorganic syntheses, v.40  

CERN Multimedia

The volumes in this continuing series provide a compilation of current techniques and ideas in inorganic synthetic chemistry. Includes inorganic polymer syntheses and preparation of important inorganic solids, syntheses used in the development of pharmacologically active inorganic compounds, small-molecule coordination complexes, and related compounds. Also contains valuable information on transition organometallic compounds including species with metal-metal cluster molecules. All syntheses presented here have been tested.

Busch, Daryle H

2009-01-01

117

Coalescence of pendant droplets on an inclined super-hydrophobic substrate  

Science.gov (United States)

Dynamics of micro droplets, coalescence underneath an inclined hydrophobic surface is explored, experimentally as well as computationally. Such a situation often arises during dropwise condensation, atmospheric dew formation, condensation in green houses, and metal vapor condensation during enrichment process, etc. Coalescence induced instability in the pendant mode is an effective means of passively enhancing heat transfer coefficient during dropwise condensation. Inclined substrates have natural advantages in terms of rendering effective passive sweeping of drops from the substrate, thereby exposing fresh preferred sites for renucleation. As compared to coalescences of sessile droplets, pendant mode induces flow instabilities at a much faster rate, thereby enhancing the associated heat/ mass transport characteristics. Against this background, the present study reports an experiment involving the coalescence of water drops in pendant mode on an inclined hydrophobic copper substrate of size 20 mm × 20 mm × 2 mm. The substrate has been prepared by developing a monolayer of n-octadecanethiol on it by chemical action. This work focuses on fundamental understanding of the mechanism of drop coalescence underneath an inclined super-hydrophobic substrate to provide aid in controlling and promoting dropwise mode of condensation in order to increase efficiency of condenser or to aid in enrichment of heavy liquid metals in closed vacuum condition. The coalescence process gets initiated by the extra available surface energy which gets released in the process. Immediately afterwards, the process of oscillating free surface formed during the coalescence is limited by viscous and inertia forces. The free surface oscillations can last ~ 10 to 100 milliseconds, depending on the size of droplets and their thermophysical properties. Depending on the local wettability, size of drops which are coalescing, substrate inclination and pinning/de-pinning behavior, droplet instability conditions are generated, which result in its slide-off motion on the substrate.

Sikarwar, Basant Singh; Khanderkar, Sameer; Muralidhar, K.

2013-07-01

118

Rapid deceleration-driven wetting transition during pendant drop deposition on superhydrophobic surfaces.  

UK PubMed Central (United Kingdom)

A hitherto unknown mechanism for wetting transition is reported. When a pendant drop settles upon deposition, there is a virtual "collision" where its center of gravity undergoes rapid deceleration. This induces a high water hammer-type pressure that causes wetting transition. A new phase diagram shows that both large and small droplets can transition to wetted states due to the new deceleration driven and the previously known Laplace mechanisms, respectively. It is explained how the attainment of a nonwetted Cassie-Baxter state is more restrictive than previously known.

Kwon HM; Paxson AT; Varanasi KK; Patankar NA

2011-01-01

119

Rapid Deceleration-Driven Wetting Transition during Pendant Drop Deposition on Superhydrophobic Surfaces  

Science.gov (United States)

A hitherto unknown mechanism for wetting transition is reported. When a pendant drop settles upon deposition, there is a virtual “collision” where its center of gravity undergoes rapid deceleration. This induces a high water hammer-type pressure that causes wetting transition. A new phase diagram shows that both large and small droplets can transition to wetted states due to the new deceleration driven and the previously known Laplace mechanisms, respectively. It is explained how the attainment of a nonwetted Cassie-Baxter state is more restrictive than previously known.

Kwon, Hyuk-Min; Paxson, Adam T.; Varanasi, Kripa K.; Patankar, Neelesh A.

2011-01-01

120

MULTIFUNCTIONAL ALCOHOLS OBTAINED FROM CARDANOL, MULTIFUNCTIONAL ACRYLIC CROSSLINKER AND PENDANT PHOSPHOROUS FLAME RETARDANT DERIVATIVES THEREOF  

UK PubMed Central (United Kingdom)

Multifunctional alcohols, polyols derived from cardanol containing at least 3 hydroxyl groups are disclosed. Such alcohols allow for synthesis of multifunctional crosslinkers such as acrylates, epoxies, and vinyl ethers and flame retardants such as >phosphates. The multifunctional alcohols or polyols can be used in polyurethanes and polycarbonates. The multifunctional crosslinkers can be used in optical coating and waveguide compositions to increase curing speed and crosslink density. The multifunctional phosphates can be used in flame resistant plastics as the highly pendant phosphorus containing phosphate non-halogen flame retardant additives.

PRASAD VADAKKETHONIPPURATHU SIVANKUTTY NAIR; PILLAI CHENNAKKATTU KRISHNA SADASIVAN

 
 
 
 
121

Multifunctional alcohols obtained from cardonal, multifunctional acrylic crosslinker and pendant phosphorous flame retardant derivatives thereof  

UK PubMed Central (United Kingdom)

Multifunctional alcohols, polyols derived from cardanol containing at least 3 hydroxyl groups are disclosed. Such alcohols allow for synthesis of multifunctional crosslinkers such as acrylates, epoxies, and vinyl ethers and flame retardants such as phosphates. The multifunctional alcohols or polyols can be used in polyurethanes and polycarbonates. The multifunctional crosslinkers can be used in optical coating and waveguide compositions to increase curing speed and crosslink density. The multifunctional phosphates can be used in flame resistant plastics as the highly pendant phosphorus containing phosphate non-halogen flame retardant additives.

PRASAD VADAKKETHONIPPURATHU SI; PILLAI CHENNAKKATTU KRISHNA SA

122

MULTIFUNCTIONAL ALCOHOLS OBTAINED FROM CARDANOL, MULTIFUNCTIONAL ACRYLIC CROSSLINKER AND PENDANT PHOSPHOROUS FLAME RETARDANT DERIVATIVES THEREOF  

UK PubMed Central (United Kingdom)

Multifunctional alcohols, polyols derived from cardanol containing at least 3 hydroxyl groups are disclosed. Such alcohols allow for synthesis of multifunctional crosslinkers such as acrylates, epoxies, and vinyl ethers and flame retardants such as phosphates. The multifunctional alcohols or polyols can be used in polyurethanes and polycarbonates. The multifunctional crosslinkers can be used in optical coating and waveguide compositions to increase curing speed and crosslink density. The multifunctional phosphates can be used in flame resistant plastics as the highly pendant phosphorus containing phosphate non-halogen flame retardant additives.

PRASAD VADAKKETHONIPPURATHU SIVANKUTTY NAIR; PILLAI CHENNAKKATTU KRISHNA SADASIVAN

123

Effects of Arm Number and Arm Length on Thermal Properties of Linear and Star-shaped Poly(D,L-lactide)s  

Directory of Open Access Journals (Sweden)

Full Text Available Influences of arm number and arm length of poly(D,L-lactide)s (PDLLs) on their thermal properties were investigated. The PDLLs with linear (1 arm) and star (4, 6 and 16 arms) shapes were synthesized via ring-opening polymerization of DLL monomer in bulk at 130°C for 24 h under nitrogen atmosphere. Stannous octoate was used as a catalyst. Initiators containing hydroxyl end groups of 1, 4, 6 and 16 were chosen as core molecules for synthesizing 1-, 4-, 6- and 16-armed PDLLs, respectively. Thermal properties of the PDLLs observed from their differential scanning calorimetric and thermogravimetric thermograms strongly depended upon their arm numbers and arm lengths. For the same DLL/initiator ratio (208/1 by mole), glass transition temperatures (Tg) and temperatures of maximum decomposition rate (Td, max) of the PDLLs decreased when the arm length decreased (or arm number increased). For similar PDLL arm lengths (4,500 and 4,900 g moL-1 for 6-armed star-shaped and 1-armed linear PDLLs, respectively), the Tg and Td, max of star-shaped PDLL was higher than that of the linear PDLL.

Mangkorn Srisa-ard; Yodthong Baimark

2010-01-01

124

Drilling arm. Bohrarm  

Energy Technology Data Exchange (ETDEWEB)

A drilling arm with a bracket, an extension arm pivoted thereon, which may be telescopic, which arm is displaceable via a lifting and lowering cylinder and a swivelling cylinder, the extension arm on its distal end, which may be rotatable about the longitudinal axis of the extension arm supporting a pivot axis, mounted for example in a fork head, on which axis a support pivotable by means of cylinders or the like is mounted, in which support a support shaft is mounted so as to be arranged substantially normal to the pivot axis, which shaft supports the drill mounting holder with a drill mounting device, a drilling device, and optionally an anchor setting device, characterised in that on the support shaft an arm is mounted, which has at its distal end a further shaft which is connected to the mounting holder, the support shaft and the further shaft being arranged substantially parallel to one another.

Kortan, O.; Schoen, K.

1988-01-07

125

Microarray Spot Synthesizer  

Science.gov (United States)

The Microarray Spot Synthesizer, developed at Davidson College, is an electronic resource that permits faculty to generate simulated DNA microarray data for use in their teaching. The Spot Synthesizer is not intended to produce real data; its purpose is to enable teachers to help students improve their ability to work efficiently with experimental data by giving them practice with known outcomes.

A. Malcolm Campbell (Davidson College;Martin Genomics Program- Biology); William T. Hatfield (Davidson College;Biology Department); Laurie J. Heyer (Davidson College;Mathematics); Verna Miller Case (University of Miami ;)

2010-05-28

126

Robot Arm Tutorial  

Science.gov (United States)

This tutorial provides background information on robotic arm technology and practical instructions for building your own. The author includes free-body diagrams, schematic drawings, help with performing force calculations in the joints, directions for setting torque parameters, and detailed explanations of each component in the system. For learners with little background in physics or engineering, the Robot Arm Calculator Tool determines the lifting capability of the robot arm. This resource is appropriate for courses in introductory physics or applied physics.

2012-03-15

127

Hydraulic Arm Challenge  

Science.gov (United States)

Students design and build a mechanical arm that lifts and moves an empty 12-ounce soda can using hydraulics for power. Small design teams (1-2 students) design and build a single axis for use in the completed mechanical arm. One team designs and builds the grasping hand, another team the lifting arm, and a third team the rotation base. The three design groups must work to communicate effectively through written and verbal communication and sketches.

The Tufts Center For Engineering Educational Outreach

128

Modelling of bionic arm  

Directory of Open Access Journals (Sweden)

Full Text Available The bionic arm is a prosthesis which will allow the amputees to control it with the help of their own brain instead of depending upon the mechanical functions of the artificial limbs which are at present available in the market. A complex design of control systems is embedded in the bionic arm which will receive and analyze the signals from the brain and convert the electrical energy to mechanical energy, making the bionic arm move.

Amartya Ganguly

2010-01-01

129

The arms race  

Energy Technology Data Exchange (ETDEWEB)

This book presents a comprehensive examination of the nature of the contemporary arms race, the forces that encourage arms competition, and the means by which these forces can be controlled. The author provides analyses of such specific issues as the viability of arms control agreements; the possibilities for nuclear disarmament; the means of deterrence, detection, and defense; and the methods of destruction themselves - nuclear, conventional, chemical, and space weapons.

Sheehan, M.

1983-01-01

130

Dean Kamen's Artificial Arm  

Science.gov (United States)

This 6-minute video chronicles the efforts of inventor/physicist Dean Kamen to develop a robotic arm with the functionality and dexterity of its human counterpart. "Prosthetic legs are in the 21st Century," says Kamen. "With prosthetic arms, we're in the Flintstones." The result of the project was the "Luke Arm", controlled with non-invasive measures using an interface like a joystick. This video is part of a series about advances in prosthetic arms, published by Inside Technology Spectrum a magazine sponsored by the Institute of Electrical and Electronics Engineers (IEEE).

2012-03-15

131

Biodegradable amphiphilic triblock copolymer bearing pendant glucose residues: preparation and specific interaction with Concanavalin A molecules.  

Science.gov (United States)

A novel biodegradable amphiphilic block copolymer PLGG-PEG-PLGG bearing pendant glucose residues is successfully prepared by the coupling reaction of 3-(2-aminoethylthio)propyl-alpha-D-glucopyranoside with the pendant carboxyl groups of PLGG-PEG-PLGG in the presence of N,N'-carbonyldiimidazole. The polymer PLGG-PEG-PLGG, i.e., poly{(lactic acid)-co-[(glycolic acid)-alt-(L-glutamic acid)]}-block-poly(ethylene glycol)-block- poly{(lactic acid)-co-[(glycolic acid)-alt-(L-glutamic acid)]}, is prepared by ring-opening copolymerization of L-lactide (LLA) with (3s)-benzoxylcarbonylethylmorpholine-2,5-dione (BEMD) in the presence of dihydroxyl PEG with molecular weight of 2000 as macroinitiator and Sn(Oct)2 as catalyst, and then by catalytic hydrogenation. The glucose-grafted copolymer shows a lower degree of cytotoxicity to ECV-304 cells and improved specific recognition and binding with Concanavalin A (Con A). Therefore, this kind of glucose-grafted copolymer may find biomedical applications. PMID:16768401

Lu, Changhai; Chen, Xuesi; Xie, Zhigang; Lu, Tiancheng; Wang, Xin; Ma, Jia; Jing, Xiabin

2006-06-01

132

Biodegradable amphiphilic triblock copolymer bearing pendant glucose residues: preparation and specific interaction with Concanavalin A molecules.  

UK PubMed Central (United Kingdom)

A novel biodegradable amphiphilic block copolymer PLGG-PEG-PLGG bearing pendant glucose residues is successfully prepared by the coupling reaction of 3-(2-aminoethylthio)propyl-alpha-D-glucopyranoside with the pendant carboxyl groups of PLGG-PEG-PLGG in the presence of N,N'-carbonyldiimidazole. The polymer PLGG-PEG-PLGG, i.e., poly{(lactic acid)-co-[(glycolic acid)-alt-(L-glutamic acid)]}-block-poly(ethylene glycol)-block- poly{(lactic acid)-co-[(glycolic acid)-alt-(L-glutamic acid)]}, is prepared by ring-opening copolymerization of L-lactide (LLA) with (3s)-benzoxylcarbonylethylmorpholine-2,5-dione (BEMD) in the presence of dihydroxyl PEG with molecular weight of 2000 as macroinitiator and Sn(Oct)2 as catalyst, and then by catalytic hydrogenation. The glucose-grafted copolymer shows a lower degree of cytotoxicity to ECV-304 cells and improved specific recognition and binding with Concanavalin A (Con A). Therefore, this kind of glucose-grafted copolymer may find biomedical applications.

Lu C; Chen X; Xie Z; Lu T; Wang X; Ma J; Jing X

2006-06-01

133

Tectonic evolution of the Oak Creek Volcanic Roof Pendant, eastern Sierra Nevada, California  

Energy Technology Data Exchange (ETDEWEB)

Detailed mapping, newly obtained U/Pb age analyses, and finite strain studies completed on a deformed volcanic roof pendant within the eastern Sierra indicate that: (1) little or no penetrative deformation affected the area during the Late Jurassic, and (2) the penetrative structure postdates the Nevadan orogeny by approximately 50 million years. The pendant consists of two volcanic sequences: a steeply dipping, homoclinal series of felsic ash flows and intermediate flows of Mid- to Late Jurassic age and an unconformably overlying series of felsic ash flows and mafic tuffs of Late Cretaceous age. Both sequences possess a single, well-developed, subvertical foliation that trends NNW. Quantitative strain analyses indicate that both the Jurassic and Cretaceous volcanic sequences underwent identical compressional strains of 30-40% shortening. This observation precludes the possibility that significant ductile deformation accompanied the rotation of the Jurassic volcanic rocks and suggests that the penetrative fabric developed within both units is Late Cretaceous in age. Isotopic age determinations on adjacent undeformed or only weakly deformed granitic plutons further indicate that the peak of deformation occurred prior to 102 Ma. Structural considerations and arguments based on the orientation of dikes of the Independence suite suggest that rotation of the Jurassic volcanic sequence took place prior to 148 Ma. in an extensional regime rather than during a Nevadan compressional event as generally interpreted.

Longiaru, S.

1987-01-01

134

Engine rocker arm assembly  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a rocker arm assembly of pedestal-mounted rocker arms adapted to be supported on an engine comprising: rocker arms, each having a bottom concave semicylindrical bearing surface having a flat-sided opening therein; fulcrum support means respectively associated with each rocker arm. Each support means has a semicylindrical body portion having a lower bearing surface slidably mating with the rocker arm bottom surface to form a pivot axis and having a flat-sided shank portion projecting downwardly from the lower bearing surface, through the opening in the rocker arm surface in relative rotation preventing rotation therewith, to a distal end adapted to engage an engine mounting surface; and a retainer means having a plurality of apertures respectively associated with each of the rocker arms. Each aperture receives and nonremovable engages the flat sides of the shank portion of the fulcrum support means in relative rotation preventing relation therewith such that a permanent assembly of the rocker arms, fulcrum support means, and retainer means is formed.

Belsanti, J.F.

1987-03-31

135

Inorganic Syntheses, 35  

CERN Multimedia

The Inorganic Syntheses series provides all users of inorganic substances with detailed and foolproof procedures for the preparation of important and timely compounds.: Includes complete, up-to-date procedures involving important inorganic substances; Contains subject, contributor, and formula indexes

Rauchfuss, Thomas

2010-01-01

136

Nuclear arms control  

Energy Technology Data Exchange (ETDEWEB)

Limited success in arms-control negotiations has left many in the national defense community frustrated and even pessimistic about the viability of nuclear treaties. Particularly frustrated are arms-control specialists who lack a simplified method for developing clear, defensible negotiating positions. The author thought the problems of arms-control negotiation stemmed from two sources: unclear national security policy, and vague methodologies for formulating negotiating positions; he believed he could do something about the second. This work offers a mathematical process for quantifying the net worth of nuclear arms control factors by addressing the interrelationships among weapons, yields, strategies, and force levels. The author sought to provide the analytical tool that could lead to consensus about the methods, and eventually the goals, of nuclear arms control.

Schaefer, H.W.

1986-04-01

137

Synthesis and chiral recognition of nickel(II) macrocyclic complex with (R)-naphthylethyleneamine pendant groups and its self-assembled framework.  

UK PubMed Central (United Kingdom)

A novel nickel(II) hexaaza macrocyclic complex, [Ni(L(R,R))](ClO(4))(2) (1), containing chiral pendant groups was synthesized by an efficient one-pot template condensation and characterized (L(R,R) ?1,8-di((R)-?-methylnaphthyl)-1,3,6,8,10,13-hexaazacyclotetradecane). The crystal structure of compound 1 was determined by single-crystal X-ray analysis. The complex was found to have a square-planar coordination environment for the nickel(II) ion. Open framework [Ni(L(R,R))](3) [C(6)H(3)(COO)(3)](2) (2) was constructed from the self-assembly of compound 1 with deprotonated 1,3,5-benzenetricarboxylic acid, BTC(3-). Chiral discrimination of rac-1,1'-bi-2-naphthol and rac-2,2,2-trifluoro-1-(9-anthryl)ethanol was performed to determine the chiral recognition ability of the chiral complex (1) and its self-assembled framework (2). Binaphthol showed a good chiral discrimination on the framework (2). The optimum experimental conditions for the chiral discrimination were examined by changing the weight ratio between the macrocyclic complex 1 or self-assembled framework 2 and racemates. The detailed synthetic procedures, spectroscopic data including single-crystal X-ray analysis, and the results of the chiral recognition for the compounds are described.

Min KS; Park MJ; Ryoo JJ

2013-01-01

138

Rocker arm construction  

Energy Technology Data Exchange (ETDEWEB)

A rocker arm is described for an internal combustion engine, the rocker arm mounting thereon a concentrically mounted cam roller engaging and rotating with a cam on the rotatable cam shaft of the engine, the rocker arm being elongated and having side and end walls and a bottom wall, and comprising an open, generally flat-topped tub-like container. One end of the rocker arm is provided with a generally concave semi-spherical depression, so as to be supported on a complementary shaped semi-spherical member at a fixed height, and the other end of which engages the stem of a valve of the engine. The rocker arm pivotable about its fixed height end by means of the cam engaging the cam roller to thus operate the valve, the rocker arm functioning as a reservoir for oil in which the cam roller rotates. The cam roller is rotatably mounted on a roller shaft journaled in circular openings in the side walls of the rocker arm and having anti-friction means comprising needle bearings surrounding its supporting shaft.

Malhorta, S.

1986-09-30

139

High-efficiency bipolar electroluminescent polymer containing an oxadiazole pendant group  

International Nuclear Information System (INIS)

By introducing electron-deficient 1,3,4-oxadiazole pendant units into poly(p-phenylenevinylene) as a side chain, we have achieved high-performance polymer light-emitting diodes with aluminum (Al) electrodes and a luminance efficiency of ? 20 cd/A. These results are attributed to the high electron affinity and the good electron transport of the oxadiazole units, which facilitate electron injection from the Al electrode, and bipolar transport in the active layer. The 'bipolar' nature of this system is strongly supported by the time-of-flight measurements, which exhibit symmetric photocurrent transients between the electrons and holes, these transients are mainly responsible for the excellent performance of this system because the help achieve charge balance in the devices.

2005-01-01

140

Pendant thiol groups-attached Pd(II) for initiating metal deposition  

Energy Technology Data Exchange (ETDEWEB)

A new activation method has been developed for initiating electroless metal deposition on silicon substrates without SnCl{sub 2} sensitization and roughening condition. Silicon wafers are first coated with thiol-terminated self-assembled monolayers (SAMs), and then catalyzed with a stable tin-free Pd(II)-based colloidal solution. Atomic force microscopy (AFM), Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS) were used to characterize the step-by-step surfaces and study the binding mechanism of Pd(II) with SAMs onto surfaces. Results show that Pd(II) oligomer particles are chemisorbed on pendant thiol surfaces through S-Pd bonds. This process involves fewer steps than the conventional Sn/Pd combined activation one. Furthermore, the chemical bound initiator possesses longevity and can be stored for a long time before metallization.

Xu Lina; Liao Jianhui; Huang Lan; Gu Ning; Zhang Haiqian; Liu Juzheng

2003-04-30

 
 
 
 
141

Investigation of the effect of temperature and pressure of wettability using modified pendant drop method  

Energy Technology Data Exchange (ETDEWEB)

Wettability is a key parameter that affects the petrophysical properties of reservoir rocks. The objective of the present work is to investigate the influence of temperature and pressure on the wettability of reservoir rocks. An experimental method for die measurements of contact angle at elevated temperature and pressure has been developed, in which a Pendant Drop Interfacial Tension Cell was modified. Experimental results of contact angle and interfacial tension for two different crude oil-brine-quartz/calcite and mineral oil-distilled water systems over a range of temperatures and pressures are reported. Contact angle for the systems studied increased with pressure, increased with temperature for sandstone system and decreased with temperature for carbonate system.

Wang, W.; Gupta, A.

1995-12-31

142

Measurement of interfacial tension by use of pendant drop video techniques  

Energy Technology Data Exchange (ETDEWEB)

This report describes an instrument to measure the interfacial tension (IFT) of aqueous surfactant solutions and crude oil. The method involves injection of a drop of fluid (such as crude oil) into a second immiscible phase to determine the IFT between the two phases. The instrument is composed of an AT-class computer, optical cell, illumination, video camera and lens, video frame digitizer board, monitor, and software. The camera displays an image of the pendant drop on the monitor, which is then processed by the frame digitizer board and non-proprietary software to determine the IFT. Several binary and ternary phase systems were taken from the literature and used to measure the precision and accuracy of the instrument in determining IFTs. A copy of the software program is included in the report. A copy of the program on diskette can be obtained from the Energy Science and Technology Software Center, P.O. Box 1020, Oak Ridge, TN 37831-1020. The accuracy and precision of the technique and apparatus presented is very good for measurement of IFTs in the range from 72 to 10{sup {minus}2} mN/m, which is adequate for many EOR applications. With modifications to the equipment and the numerical techniques, measurements of ultralow IFTs (<10{sup {minus}3} mN/m) should be possible as well as measurements at reservoir temperature and pressure conditions. The instrument has been used at the Idaho National Engineering Laboratory to support the research program on microbial enhanced oil recovery. Measurements of IFTs for several bacterial supernatants and unfractionated acid precipitates of microbial cultures containing biosurfactants against medium to heavy crude oils are reported. These experiments demonstrate that the use of automated video imaging of pendant drops is a simple and fast method to reliably determine interfacial tension between two immiscible liquid phases, or between a gas and a liquid phase.

Herd, M.D.; Thomas, C.P.; Bala, G.A.; Lassahn, G.D.

1993-09-01

143

ARM review, 1991  

Energy Technology Data Exchange (ETDEWEB)

The Department of Energy's Atmospheric Radiation Measurement Program (ARM) is a major component of the US research program in global change. ARMs goals of quantifying the effect of clouds on the earth's radiation budget is a key element in improving general circulation models (GCM) through enhancing understanding of the fast physics of the atmosphere. ARM is a well organized and managed program. A major concern for the programs future is the availability of adequate resources to establish and maintain observation sites in the Western tropical Pacific and on the north slope of Alaska.

Cornwall, J.; Dyson, F.; Flatte, S.; Koonin, S.; MacDonald, G.; Nierenberg, W.; Rothaus, O.; Zachariasen, F.

1992-02-01

144

ARM review, 1991  

Energy Technology Data Exchange (ETDEWEB)

The Department of Energy`s Atmospheric Radiation Measurement Program (ARM) is a major component of the US research program in global change. ARMs goals of quantifying the effect of clouds on the earth`s radiation budget is a key element in improving general circulation models (GCM) through enhancing understanding of the fast physics of the atmosphere. ARM is a well organized and managed program. A major concern for the programs future is the availability of adequate resources to establish and maintain observation sites in the Western tropical Pacific and on the north slope of Alaska.

Cornwall, J.; Dyson, F.; Flatte, S.; Koonin, S.; MacDonald, G.; Nierenberg, W.; Rothaus, O.; Zachariasen, F.

1992-02-01

145

ARM review, 1991  

Energy Technology Data Exchange (ETDEWEB)

The Department of Energy's Atmospheric Radiation Measurement Program (ARM) is a major component of the U.S. research program in global change. ARMs goals of quantifying the effect of clouds on the earth's radiation budget is a key element in improving global circulation models (GCM) through enhancing understanding of the fast physics of the atmosphere. ARM is a well organized and managed program. A major concern for the programs future is the availability of adequate resources to establish and maintain observation sites in the Western tropical Pacific and on the north slope of Alaska.

MacDonald, G.

1992-01-20

146

Arm support apparatus  

UK PubMed Central (United Kingdom)

Arm support apparatus, for independently supporting an arm section and a forearm section of an injured arm of a user has a support body including elbow, forearm and wrist supports, a front portion located away from a torso of the user and a rear portion disposed towards the torso. The apparatus includes a first shoulder strap for supporting the forearm section and having strap ends connected respectively to a first front portion connector connected to the front portion and to a first rear portion connector connected to the rear portion, both located towards the wrist support. A second shoulder strap for supporting the arm section has strap ends connected respectively to a second front portion connector connected to the front portion towards the elbow support and spaced apart from the first front portion connector and to the body towards the wrist support.

AVON GUY

147

Modeling armed conflicts.  

UK PubMed Central (United Kingdom)

Armed conflicts have been prevalent throughout history, in some cases having very great consequences. To win, one needs to understand the characteristics of an armed conflict and be prepared with resources and capabilities for responding to its specific challenges. An important tool for understanding these characteristics and challenges is a model--an abstraction of the field of conflict. Models have evolved through the years, addressing different conflict scenarios with varying techniques.

Kress M

2012-05-01

148

Process for synthesizing dialkyldiphenylamine  

UK PubMed Central (United Kingdom)

The invention discloses a synthesizing method of dialkyldiphenylamine, which is characterized by the following: adopting diphenylamine and diisobutylene as raw material making catalyst through H beta zeolite and gamma-Al2O3 operating continuously under liquid-phase condition regenerating and recycling catalyst reducing manufacturing cost.

MA HAO AI

149

Inorganic syntheses, v.64  

CERN Document Server

The Inorganic Synthesis Series provides all users of inorganic substances with detailed and foolproof procedures for the preparation of important and timely compounds. This new volume includes information on water-solubilizing ligands for organometallics, labile ligand complexes, and the syntheses of cluster compounds and hydrides.

Darensbourg, Marcetta York

2009-01-01

150

Infinitely many-armed bandits  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We consider multi-armed bandit problems where the number of arms is larger than the possible number of experiments. We make a stochastic assumption on the mean-reward of a new selected arm which characterizes its probability of being a near-optimal arm. Our assumption is weaker than in previous work...

Wang, Yizao; Audibert, Jean-Yves; Munos, Rémi

151

Method for synthesizing Seocalcitol  

UK PubMed Central (United Kingdom)

The invention provides a method for synthesizing Seocalcitol, which mainly solves the technical problem of high production cost, difficult product purification and the like in the conventional synthetic method. The method comprises the following steps of: performing a Wittig/Wittig-Horner Julia/Horner-Wadsworth-Emmons name reaction by utilizing an aldehyde intermediate 7 and a Ylide intermediate 2 under the action of an alkali to construct carbon-carbon double bonds so as to form a precursor compound 10 of Seocalcitol, and then performing an illumination reaction and a deprotection reaction to prepare Seocalcitol 11. The invention also provides a method for synthesizing the key Ylide intermediate 2. The method has the advantages of simple operation, no side reaction, convenient purification, high yield and low cost, and is suitable for preparing high-purity Seocalcitol products through industrial production.

HUAWEI CHENG; XIAOYONG LI; ZHESHENG LIU

152

Method for synthesizing clethodim  

UK PubMed Central (United Kingdom)

The invention relates to a method for synthesizing clethodim, in particular to a process for synthesizing an agricultural herbicide clethodim, namely (+/-)-2-[(E)-3-chloro-allyloxyimino]propyl-5-[2-(ethylthio)propyl]-3-hydroxy-cyclohexyl-2-keten. The method uses petroleum ether as a solvent and a ketone complex as a stabilizing agent to perform condensation reaction on propyl-triketone and allyl amine oxide to prepare the clethodim. Under the condition that the ketone complex serves as the stabilizing agent, the method can perform the condensation reaction at a low temperature by using the petroleum ether as the solvent, and prevent the clethodim product obtained through the reaction from being decomposed due to a high temperature to cause yield declination and content to decrease, thus the yield of the method can reach about 97 percent and the content reaches 94 percent.

GUOQUAN YU; WEI YU; ZHIYANG JI; JIANRONG WANG

153

Counterbalanced refueling arm assembly  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a counter balanced refueling arm. It comprises: a supporting platform, wheels supporting the platform, an outer caster assembly. The wheel, a first swivel joint mounted on the outboard caster assembly having a substantially vertical axis of rotation, an inlet and an outlet defined on the joint, a fuel supply conduit communicating with the joint inlet, a second swivel joint mounted on the platform having a substantially horizontal axis of rotation, an inlet and an outlet, a rigid conduit interconnecting the first joint outlet with the second joint inlet establishing communication between the first and second joint, a substantially rigid arm conduit having an axis, an inner end affixed to and communicating with the second joint outlet and an outer end. The arm conduit being pivoted about the second joint axis within a substantially vertical plane, a first elbow swivel coupling having an inlet connected to the arm conduit outer end, an outlet and an axis of rotation transverse to the arm conduit axis, a second elbow swivel coupling having an inlet connected to the first coupling outlet, an outlet and an axis of rotation transverse to aid first coupling axis, a third elbow swivel coupling having an inlet connected to the second coupling outlet, an outlet and an axis of rotation transverse to the coupling axis, and a nozzle connected to the third coupling outlet.

Fournier, P.J.E.; Reinker, J.F., Jr.

1990-02-06

154

The influence of pendant carboxylic acid loading on surfaces of statistical poly(4-hydroxystyrene)-co-styrene)s  

DEFF Research Database (Denmark)

Copolymers 9f 4-tert-butoxystyrene (tB5) and styrene (5) have been prepared by free radical copolymerization and the copolymer ratios of TtBS == 0.97 and Ts == 1.12 have been determined by the Kelen-Tiidos method. After deprotection to 4-hydroxystyrene, alkynes were introduced by a Williamson ether synthesis with propargyl bromide and the copolymers were functionalized with pendant aliphatic or aromatic carboxylic acids by click chemistry. Differential scanning calorimetry of the copolymers demonstrates the large influence on Tg ofthe different functional groups and the backbone composition. In particular, aliphatic and aromatic pendant groups differ by 92°C in Tg• Contact angle measurements onspin coated films have shown a maximum effect of the functional groups in the advancing contact angle at a 75/100 copolymer loading. In addition to this, X-ray photoelectron spectroscopy shows the presence of acid groups on the surface.

Daugaard, Anders Egede; Hvilsted, SØren

2008-01-01

155

The Gesture Pendant: A Self-illuminating, Wearable, Infrared Computer Vision System for Home Automation Control and Medical Monitoring  

UK PubMed Central (United Kingdom)

In this paper we present a wearable device for control of home automation systems via hand gestures. This solution has many advantages over traditional home automation interfaces in that it can be used by those with loss of vision, motor skills, and mobility. By combining other sources of context with the pendant we can reduce the number and complexity of gestures while maintaining functionality. As users input gestures, the system can also analyze their movements for pathological tremors. This information can then be used for medical diagnosis, therapy, and emergency services.Currently, the Gesture Pendant can recognize control gestures with an accuracy of 95% and user defined gestures with an accuracy of 97% It can detect tremors above 2HZ within /- Hz.

Thad Starner; Jake Auxier; Daniel Ashbrook; Maribeth Gandy

156

Arm To Arm Interface Using Embedded C  

Directory of Open Access Journals (Sweden)

Full Text Available Embedded systems are the most emerging field in these recent years. In this paper a different number of ARM processors (LPC2148 and LPC2378) are interconnected using C for distributed services. N numbers of processors are connected as the network and each processing devices are interlinked with each other, so that the each data that is processed by the devices and it can be used by the other device to activate their entire process. All the processed data’s are communicated to other device through Xbee interface card. LPC2148 and LPC2378 ARM processors are used in this prototype and winXtalk is used as a software terminal window. In this paper, the ultimate benefits of multiple processor interactions related to the embedded applications and design issues of processor interconnection are discussed. The features of multiple processor interaction in inter process communication and executions of embedded multitasking are also discussed. In modern embedded computing platform, embedded processor used in various applications like home automation, industrial control, medical system, access control, etc. In this paper, using embedded processor interactions, the several data communication is established.

Manivannan.D; Mohanraj.C

2013-01-01

157

Direct Four-Electron Reduction of O2 to H2 O on TiO2 Surfaces by Pendant Proton Relay.  

Science.gov (United States)

Relay race: By using polyprotic-acid-based pendant proton relays (phosphate, L-glutamic acid, and malonic acid), the oxygen reduction reaction (ORR) on a TiO2 surface is switched from a single-electron process to a concerted 4?e(-) /4?H(+) reduction to H2 O. In contrast, monocarboxylic acids (PA and AA) without pendant proton relays only enhance the ORR reduction rate but barely change the reaction pathway. PMID:23873729

Sheng, Hua; Ji, Hongwei; Ma, Wanhong; Chen, Chuncheng; Zhao, Jincai

2013-07-19

158

Direct Four-Electron Reduction of O2 to H2 O on TiO2 Surfaces by Pendant Proton Relay.  

UK PubMed Central (United Kingdom)

Relay race: By using polyprotic-acid-based pendant proton relays (phosphate, L-glutamic acid, and malonic acid), the oxygen reduction reaction (ORR) on a TiO2 surface is switched from a single-electron process to a concerted 4?e(-) /4?H(+) reduction to H2 O. In contrast, monocarboxylic acids (PA and AA) without pendant proton relays only enhance the ORR reduction rate but barely change the reaction pathway.

Sheng H; Ji H; Ma W; Chen C; Zhao J

2013-09-01

159

THE INTERNATIONAL ARMS TRADE  

Directory of Open Access Journals (Sweden)

Full Text Available Everyone is aware of the existence of the arms trade but few have any idea of the nature of its workings or of its implications, both actual and potential. Some information as to the methods employed in the sale of arms was made available via the Lockheed and Northrop scandals, but by and large this was information that could not be evaluated in terms of all the elements of the system. It is the aim of this article to provide some insight into the various facets that go together to make up the arms trade, in this way by no means giving an all-embracing account but merely providing some interesting facts and figures.

M. Japhet

2012-01-01

160

Unifying robot arm control  

Energy Technology Data Exchange (ETDEWEB)

The authors present a unified approach to three stages of robot arm control based on the Newton-Euler equations of motion. The stages unified are: resolved motion, gross motion, and fine motion. Apart from the conceptual advantage this unification can require less computation than if the three stages are computed separately. In particular, less computations are required for arms with no more than about a dozen joints (a number unlikely to be exceeded for most arms, at least in the near future). Computation times are estimated assuming the computing elements are fabricated from current VLSI technology. It is also shown how friction can be incorporated into the unified approach. The concept of pseudo-force is introduced to relate fine motion to the Newton-Euler equations. 19 references.

Mudge, T.N.; Turney, J.L.

1982-01-01

 
 
 
 
161

PHENIX Muon Arms  

Energy Technology Data Exchange (ETDEWEB)

The PHENIX Muon Arms detect muons at rapidities of |y|=(1.2-2.4) with full azimuthal acceptance. Each muon arm must track and identify muons and provide good rejection of pions and kaons ({approx}10{sup -3}). In order to accomplish this we employ a radial field magnetic spectrometer with precision tracking (Muon Tracker) followed by a stack of absorber/low resolution tracking layers (Muon Identifier). The design, construction, testing and expected run parameters of both the muon tracker and the muon identifier are described.

Akikawa, H.; Al-Jamel, A.; Archuleta, J.B.; Archuleta, J.R.; Armendariz, R.; Armijo, V.; Awes, T.C.; Baldisseri, A.; Barker, A.B.; Barnes, P.D.; Bassalleck, B.; Batsouli, S.; Behrendt, J.; Bellaiche, F.G.; Bland, A.W.; Bobrek, M.; Boissevain, J.G.; Borel, H.; Brooks, M.L.; Brown, A.W.; Brown, D.S.; Bruner, N.; Cafferty, M.M.; Carey, T.A.; Chai, J.-S.; Chavez, L.L.; Chollet, S.; Choudhury, R.K.; Chung, M.S.; Cianciolo, V.; Clark, D.J.; Cobigo, Y.; Dabrowski, C.M.; Debraine, A.; DeMoss, J.; Dinesh, B.V.; Drachenberg, J.L.; Drapier, O.; Echave, M.A.; Efremenko, Y.V.; En' yo, H.; Fields, D.E.; Fleuret, F.; Fried, J.; Fujisawa, E.; Funahashi, H.; Gadrat, S.; Gastaldi, F.; Gee, T.F.; Glenn, A.; Gogiberidze, G.; Gonin, M.; Gosset, J.; Goto, Y.; Granier de Cassagnac, R.; Hance, R.H.; Hart, G.W.; Hayashi, N.; Held, S.; Hicks, J.S.; Hill, J.C.; Hoade, R.; Hong, B.; Hoover, A.; Horaguchi, T.; Hunter, C.T.; Hurst, D.E.; Ichihara, T.; Imai, K.; Isenhower, L.D.L. Davis; Isenhower, L.D.L. Donald; Ishihara, M.; Jang, W.Y.; Johnson, J.; Jouan, D.; Kamihara, N.; Kamyshkov, Y.; Kang, J.H.; Kapoor, S.S.; Kim, D.J.; Kim, D.-W.; Kim, G.-B.; Kinnison, W.W.; Klinksiek, S.; Kluberg, L.; Kobayashi, H.; Koehler, D.; Kotchenda, L.; Kuberg, C.H.; Kurita, K.; Kweon, M.J.; Kwon, Y.; Kyle, G.S.; LaBounty, J.J.; Lajoie, J.G.; Lee, D.M.; Lee, S.; Leitch, M.J.; Li, Z.; Liu, M.X.; Liu, X.; Liu, Y.; Lockner, E.; Lopez, J.D.; Mao, Y.; Martinez, X.B.; McCain, M.C.; McGaughey, P.L.; Mioduszewski, S.; Mischke, R.E.; Mohanty, A.K.; Montoya, B.C.; Moss, J.M.; Murata, J.; Murray, M.M.; Nagle, J.L.; Nakada, Y.; Newby, J.; Obenshain, F.; Palounek, A.P.T.; Papavassiliou, V.; Pate, S.F.; Plasil, F.; Pope, K.; Qualls, J.M.; Rao, G.; Read, K.F. E-mail: readkf@ornl.gov; Robinson, S.H.; Roche, G.; Romana, A.; Rosnet, P.; Roth, R.; Saito, N.; Sakuma, T.; Sandhoff, W.F.; Sanfratello, L.; Sato, H.D.; Savino, R.; Sekimoto, M.; Shaw, M.R.; Shibata, T.-A.; Sim, K.S.; Skank, H.D.; Smith, D.E.; Smith, G.D. [and others

2003-03-01

162

PHENIX Muon Arms  

International Nuclear Information System (INIS)

[en] The PHENIX Muon Arms detect muons at rapidities of |y|=(1.2-2.4) with full azimuthal acceptance. Each muon arm must track and identify muons and provide good rejection of pions and kaons (?10-3). In order to accomplish this we employ a radial field magnetic spectrometer with precision tracking (Muon Tracker) followed by a stack of absorber/low resolution tracking layers (Muon Identifier). The design, construction, testing and expected run parameters of both the muon tracker and the muon identifier are described

2003-03-01

163

Binding of adenosine to pendant phenylboronate groups of thermoresponsive copolymer: a quantitative study.  

Science.gov (United States)

Binding of adenosine to the thermosensitive copolymer of N-isopropylacrylamide and 3-(acrylamido)aminophenylboronic acid (82:18, Mn = 47,000 g . mol(-1)) was studied by equilibrium dialysis at 22 degrees C and 37 degrees C, in a 0.1 M glycine buffer containing 0.1 M NaCl at pH 9.2. The copolymer exhibited a the phase transition temperature (T(p)) of 26.5 degrees C under the above conditions. At 22 degrees C the binding of adenosine to the water-soluble copolymer was well described by a Langmuir model, accounting for preferential ionisation of the boronate-nucleoside complexes and, therefore, restricted reactivity of the rest of boronates. At saturation, the copolymer contained 38% of its phenylboronic acid groups in the form of complexes, whereas the association constant was 1,400 M(-1). At 37 degrees C no binding of adenosine to thermally precipitated copolymer was found, presumably owing to interaction of the phenylboronates with hydrophobic segments of polyNIPAM. At high loading of the copolymer by the reversibly bound adenosine the T(p) steeply increases with increasing fraction of the phenylboronate-adenosine complexes in the chains. The increase of the T(p) observed above the saturating adenosine concentration (>1 x 10(-3) M, 22 degrees C) very probably testifies to competition of the nucleoside with hydrophobic polyNIPAM segments for binding to the pendant phenylboronates. PMID:16096993

Ivanov, Alexander E; Galaev, Igor Yu; Mattiasson, Bo

2005-08-12

164

Chemoenzymatically synthesized glycoconjugate polymers.  

Science.gov (United States)

Glycoconjugate polymers with poly(vinyl alcohol) (PVA) backbone were synthesized via a chemoenzymatic method. The sugar alcohols of maltose and lactose were submitted to transesterification in the presence of lipases. The esterification was achieved with high selectivity and yield, and the resulting maltitol and lactitol 6-vinyl sebacates were polymerized by a conventional radical initiator with hydrogen peroxide and ascorbic acid. The glycoconjugate polymers carrying alpha-glucose and beta-galactose as recognition signals showed the biological activity such as lectin recognition abilities and hepatocyte adhension. The biodegradability of these polymers was modest but higher than PVA. PMID:12625739

Miura, Yoshiko; Ikeda, Takayasu; Kobayashi, Kazukiyo

165

Method for synthesizing taspine  

UK PubMed Central (United Kingdom)

The invention relates to a method for synthesizing taspine. The method is characterized by comprising the following steps: taking isovanillin as a raw material, obtaining 4-methoxy-3-benzyloxy-2-methyl bromobenzoate by bromization, benzyl protection, oxidation and esterification, then obtaining a benzyl-protecting bifendate compound by an ullmann reaction, removing benzyl by palladium/carbon catalysis, selectively etherifying one of hydroxyl groups with allyl, and obtaining the taspine by Claisen rearrangement, double bonds oxidation into aldehyde, reduction and amination. The method has the advantages of mild reaction conditions, simple operation in the reaction process, cheap and available reagents, higher total yield (16.5%) and the like.

LANGCHONG HE; BIN CHENG; SANQI ZHANG; JIE ZHANG; XIAOFANG HOU; XILING LI

166

Method for synthesizing filbertone  

UK PubMed Central (United Kingdom)

The invention relates to a method for synthesizing spice with nut fragrance, namely filbertone. The method comprises the following steps: firstly, condensing butanone and acetaldehyde into 3-methyl-3-amylene-2-ketone secondly, catalytically hydrogenating the intermediate substance 3-methyl-3-amylene-2-ketone to generate an intermediate substance 3-methyl-2-pentanone finally, condensing the intermediate substance 3-methyl-3-amylene-2-ketone with acetaldehyde to generate the filbertone. In the preparation process, Grignard reaction and stoichiometric oxidation reaction are avoided. The method has small pollution, simple reaction and high product purity, and is applicable to industrial production.

CUNZHAO CHENG

167

METHOD FOR SYNTHESIZING THYMOSINS  

UK PubMed Central (United Kingdom)

The invention relates to a method for obtaining thymosins and/or the pharmaceutically acceptable salts thereof by means of solid-phase synthesis on polymeric supports, which comprises the steps of linearly synthesizing the thymus-derived peptides in solid phase, incorporating at least one Thr or Ser in the sequence, in pseudoproline dipeptide form, obtaining the thymosins by treating the peptidyl resin with trifluoroacetic acid, and purifying the thymosins by RP-HPLC. The present invention also protects the isolated and/or purified compound obtained by means of said method and also the use thereof in the preparation of a medicinal product.

FERNANDEZ CARNEADO JIMENA; PONSATI OBIOLS BERTA; CLEMENTE RODRIGUEZ JAVIER; RUBIRES FERRER RAIMON; PAVON FERNANDEZ SERGI

168

METHOD FOR SYNTHESIZING THYMOSINS  

UK PubMed Central (United Kingdom)

Method for obtaining thymosins and/or the pharmaceutically acceptable salts thereof by means of solid-phase synthesis on polymeric supports, which comprises the steps of linearly synthesizing the thymus-derived peptides in solid phase, incorporating at least one Thr or Ser in the sequence, in pseudoproline dipeptide form, obtaining the thymosins by treating the peptidile resin with trifluoroacetic acid, and purifying the thymosins by RP-HPLC. The present invention also protects the isolated and/or purified compound obtained by means of said method and also the use thereof in the preparation of a medicinal product.

FERNANDEZ CARNEADO JIMENA; PONSATI OBIOLS BERTA; CLEMENTE RODRIGUEZ JAVIER; RUBIRES FERRER RAIMON; PAVON FERNANDEZ SERGI

169

Method for synthesizing thymosins  

UK PubMed Central (United Kingdom)

The invention relates to a method for obtaining thymosins and/or the pharmaceutically acceptable salts thereof by means of solid-phase synthesis on polymeric supports, which comprises the steps of linearly synthesizing the thymus-derived peptides in solid phase, incorporating at least one Thr or Ser in the sequence, in pseudoproline dipeptide form, obtaining the thymosins by treating the peptidyl resin with trifluoroacetic acid, and purifying the thymosins by RP-HPLC. The present invention also protects the isolated and/or purified compound obtained by means of said method and also the use thereof in the preparation of a medicinal product.

JIMENA FERNANDEZ CARNEADO; BERTA PONSATI OBIOLS; JAVIER CLEMENTE RODRIGUEZ; RAIMON RUBIRES FERRER; SERGI PAVON FERNANDEZ

170

Security and arms control  

Energy Technology Data Exchange (ETDEWEB)

This book focuses on the broad analytical perspectives that are relevant to the security and arms central considerations of any national government. The chapters are organized under the following headings: Using and threatening force, The control of force and threats, Surmounting force and threats.

Kolodziej, E.A.; Morgan, P.M.

1989-01-01

171

American arms supermarket  

Energy Technology Data Exchange (ETDEWEB)

Tracing U.S. policies, practices, and experiences in military sales from the 1950s to the present, the author explains how the formation of U.S. arms exports has proved to be an unreliable instrument of policy, often producing results that diminish - rather than enhance - fundamental American interests.

Klare, M.T.

1985-01-01

172

Globalisation and Armed Conflict  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Globalization and Armed Conflict addresses one of the most important and controversial issues of our time: Does global economic integration foster or suppress violent disputes within and among states? Here, cutting-edge research by leading figures in international relations shows that expanding comm...

173

Method for synthesizing indiplon  

UK PubMed Central (United Kingdom)

The invention relates to a method for synthesizing indiplon, which comprises the following steps: using low-cost available 3-aminoacetophenone as a starting raw material reacting the 3-aminoacetophenone with acetic anhydride to convert the 3-aminoacetophenone into 3-acetamido-acetophenone reacting the obtained 3-acetamido-acetophenone with powdered potassium hydrate first and then with iodomethane to convert the 3-acetamido-acetophenone into N-methyl-N-(3-acetyl-phenyl)-acetamide reacting the obtained N-methyl-N-(3-acetyl-phenyl)-acetamide with ethyl formate under the action of sodium ethylate to obtain an alkali metal 3-(N-methyl-N-acetyl)amino-beta-ketone-phenyl-propionaldehyde enol salt and synthesizing the indiplon by condensing the obtained alkali metal 3-(N-methyl-N-acetyl) amino-beta-ketone-phenyl-propionaldehyde enol salt and (3-amino-1H-pyrazole-4-yl)-2-thiophene ketone. The method has the advantages of low cost, mild reaction condition, safety and environmental protection, and easy industrialized production, and the obtained indiplon can be used as hypnagogue for treating anhypnosis.

XIANGDONG ZHOU; CHANGRONG XU; MIN SU

174

SYNTH: A spectrum synthesizer  

International Nuclear Information System (INIS)

A computer code has been written at the Pacific Northwest Laboratory (PNL) to synthesize the results of typical gamma-ray spectroscopy experiments. The code, dubbed SYNTH, allows a use r to specify physical characteristics of a gamma-ray source, the quantity of the nuclides producing the radiation, the source-to-detector distance and the type and thickness of absorbers, the size and composition of the detector (Ge or NaI), and the electronic set up used to gather the data. In the process of specifying the parameters needed to synthesize a spectrum, several interesting intermediate results are produced, including a photopeak transmission function vs energy, a detector efficiency curve, and a weighted list of gamma and x rays produced from a set of nuclides. All of these intermediate results are available for graphical inspection and for printing. SYNTH runs on personal computers. It is menu driven and can be customized to user specifications. SYNTH contains robust support for coaxial germanium detectors and some support for sodium iodide detectors. SYNTH is not a finished product. A number of additional developments are planned. However, the existing code has been compared carefully to spectra obtained from National Institute for Standards and Technology (NIST) certified standards with very favorable results. Examples of the use of SYNTH and several spectral results will be presented

1994-01-01

175

SYNTH: A spectrum synthesizer  

International Nuclear Information System (INIS)

[en] A computer code has been written at the Pacific Northwest Laboratory (PNL) to synthesize the results of typical gamma ray spectroscopy experiments. The code, dubbed SYNTH, allows a user to specify physical characteristics of a gamma ray source, the quantity of the nuclides producing the radiation, the source-to-detector distance and the presence of absorbers, the type and size of the detector, and the electronic set up used to gather the data. In the process of specifying the parameters needed to synthesize a spectrum, several interesting intermediate results are produced, including a photopeak transmission function versus energy, a detector efficiency curve, and a weighted list of gamma and x rays produced from a set of nuclides. All of these intermediate results are available for graphical inspection and for printing. SYNTH runs on personal computers. It is menu driven and can be customized to user specifications. SYNTH contains robust support for coaxial germanium detectors and some support for sodium iodide detectors. SYNTH is not a finished product. A number of additional developments are planned. However, the existing code has been compared carefully to spectra obtained from National Institute for Standards and Technology (NIST) certified standards with very favorable results. Examples of the use of SYNTH and several spectral results are presented

1993-10-30

176

Star Formation in Spiral Arms  

CERN Document Server

The origin and types of spiral arms are reviewed with an emphasis on the connections between these arms and star formation. Flocculent spiral arms are most likely the result of transient instabilities in the gas that promote dense cloud formation, star formation, and generate turbulence. Long irregular spiral arms are usually initiated by gravitational instabilities in the stars, with the gas contributing to and following these instabilities, and star formation in the gas. Global spiral arms triggered by global perturbations, such as a galaxy interaction, can be wavemodes with wave reflection in the inner regions. They might grow and dominate the disk for several rotations before degenerating into higher-order modes by non-linear effects. Interstellar gas flows through these global arms, and through the more transient stellar spiral arms as well, where it can reach a high density and low shear, thereby promoting self-gravitational instabilities. The result is the formation of giant spiral arm cloud complexes,...

Elmegreen, Bruce G

2011-01-01

177

Baghouse with rotating sweep arm  

Energy Technology Data Exchange (ETDEWEB)

A cleaning arm for a cylindrical baghouse pivoting centrally of the clean air plenum with a cam controlled valve to provide backflushing air to successive concentric rings of filter bags with each full revolution of the cleaning arm is described.

Noland, R.D.

1980-11-11

178

Replantation (Finger, Hand, or Arm)  

Science.gov (United States)

... the surgical reattachment of a finger, hand, or arm that has been completely cut from a person’s ... the replanted part. Generally, the further down the arm the injury occurs, the better the return of ...

179

Sensitization of nanocrystalline TiO2 anchored with pendant catechol functionality using a new tetracyanato ruthenium(II) polypyridyl complex.  

UK PubMed Central (United Kingdom)

We have synthesized a new photoactive ruthenium(II) complex having a pendant catechol functionality (K(2)[Ru(CN)(4)(L)] (1) (L is 4-[2-(4'-methyl-2,2'-bipyridinyl-4-yl)vinyl]benzene-1,2-diol) for studying the dynamics of the interfacial electron transfer between nanoparticulate TiO(2) and the photoexcited states of this Ru(II) complex using femtosecond transient absorption spectroscopy. Steady-state absorption and emission studies revealed that the complex 1 showed a strong solvatochromic behavior in solvents or solvent mixtures of varying polarity. Our steady-state absorption studies further revealed that 1 is bound to TiO(2) surfaces through the catechol functionality, though 1 has two different types of functionalities (catecholate and cyanato) for binding to TiO(2) surfaces. The longer wavelength absorption band tail for 1, bound to TiO(2) through the proposed catecholate functionality, could also be explained on the basis of the DFT calculations. Dynamics of the interfacial electron transfer between 1 and TiO(2) nanoparticles was investigated by studying kinetics at various wavelengths in the visible and near-infrared region. Electron injection to the conduction band of the nanoparticulate TiO(2) was confirmed by detection of the conduction band electron in TiO(2) ([e(-)](TiO(2))(CB)) and cation radical of the adsorbed dye (1(*+)) in real time as monitored by transient absorption spectroscopy. A single exponential and pulse-width limited (<100 fs) electron injection was observed. Back electron transfer dynamics was determined by monitoring the decay kinetics of 1(*+) and [e(-)](TiO(2))(CB). This is the first report on ultrafast ET dynamics on TiO(2) nanoparticle surface using a solvatochromic sensitizer molecule.

Kar P; Verma S; Sen A; Das A; Ganguly B; Ghosh HN

2010-05-01

180

Sensitization of nanocrystalline TiO2 anchored with pendant catechol functionality using a new tetracyanato ruthenium(II) polypyridyl complex.  

Science.gov (United States)

We have synthesized a new photoactive ruthenium(II) complex having a pendant catechol functionality (K(2)[Ru(CN)(4)(L)] (1) (L is 4-[2-(4'-methyl-2,2'-bipyridinyl-4-yl)vinyl]benzene-1,2-diol) for studying the dynamics of the interfacial electron transfer between nanoparticulate TiO(2) and the photoexcited states of this Ru(II) complex using femtosecond transient absorption spectroscopy. Steady-state absorption and emission studies revealed that the complex 1 showed a strong solvatochromic behavior in solvents or solvent mixtures of varying polarity. Our steady-state absorption studies further revealed that 1 is bound to TiO(2) surfaces through the catechol functionality, though 1 has two different types of functionalities (catecholate and cyanato) for binding to TiO(2) surfaces. The longer wavelength absorption band tail for 1, bound to TiO(2) through the proposed catecholate functionality, could also be explained on the basis of the DFT calculations. Dynamics of the interfacial electron transfer between 1 and TiO(2) nanoparticles was investigated by studying kinetics at various wavelengths in the visible and near-infrared region. Electron injection to the conduction band of the nanoparticulate TiO(2) was confirmed by detection of the conduction band electron in TiO(2) ([e(-)](TiO(2))(CB)) and cation radical of the adsorbed dye (1(*+)) in real time as monitored by transient absorption spectroscopy. A single exponential and pulse-width limited (<100 fs) electron injection was observed. Back electron transfer dynamics was determined by monitoring the decay kinetics of 1(*+) and [e(-)](TiO(2))(CB). This is the first report on ultrafast ET dynamics on TiO(2) nanoparticle surface using a solvatochromic sensitizer molecule. PMID:20349939

Kar, Prasenjit; Verma, Sandeep; Sen, Anik; Das, Amitava; Ganguly, Bishwajit; Ghosh, Hirendra Nath

2010-05-01

 
 
 
 
181

The Arm Lie Group Theory  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We developp the Arm-Lie group theory which is a theory based onthe exponential of a changing of matrix variable u(X). We de ne a corresponding u-adjoint action, the corresponding commutation relations in the Arm-Lie algebra and the u-Jacobi identity. Throught the exponentiation, Arm-Lie algebras bec...

Arm, Boris

182

Arm movement effect on balance.  

UK PubMed Central (United Kingdom)

The background research shows a high incidence of falls and loss of balance related injuries, which cause serious consequences to individual health and quality of life, as well as substantial healthcare impact in services and costs. The literature review emphasizes that arm movements have a potentially significant effect on balance, and indentifies the use of balance boards as a relevant and meaningful tool for dynamic balance evaluation. The primary objective of this initial study was to develop a method to test and evaluate the effect of arm movements on the maintenance of postural stability. Further we investigated the impact of dominant and non-dominant arms, the reaction time of arms, and the amount of activity of arms related to dynamic balance control. The study applied an accelerometer-based balance board test to measure postural stability as related to arm movements. The evaluation consists of accelerometers placed on the two arms and the balance board. Data were acquired from four different subjects and processed accordingly. The finding verified that arms play an important role in the improvement of balance. Our findings suggest that the dominant arm is more active in balance control and that the movement of arms most often occurs just prior to and during loss of balance. The results also suggest that the amount of arm movement activity directly relates to balance control and the use of the dominant arm.

Shafeie M; Manifar S; Milosevic M; McConville KM

2012-01-01

183

Perspectives on the arms race  

Energy Technology Data Exchange (ETDEWEB)

The arms race and in particular its nuclear aspect is too often analyzed in a purely East--West and even a bipolar context. But with signs of lessening Soviet--American tension it may increasingly be recognized that the arms race is a multidimensional phenomenon. This book presents some perspectives on the arms race, given the current global political situation.

Carlton, D.; Schaerf, C.

1989-01-01

184

A chemical waveform synthesizer.  

UK PubMed Central (United Kingdom)

Algorithms and methods were developed to synthesize complex chemical waveforms in open volumes by using a scanning-probe microfluidic platform. Time-dependent variations and oscillations of one or several chemical species around the scanning probe, such as formation of sine waves, damped oscillations, and generation of more complex patterns, are demonstrated. Furthermore, we show that intricate bursting and chaotic calcium oscillations found in biological microdomains can be reproduced and that a biological cell can be used as a probe to study receptor functionalities as a function of exposure to time-dependent variations of receptor activators and inhibitors. Thus, the method allows for studies of biologically important oscillatory reactions. More generally, the system allows for detailed studies of complex time-varying chemical and physical phenomena in solution or at solution/surface interfaces.

Olofsson J; Bridle H; Sinclair J; Granfeldt D; Sahlin E; Orwar O

2005-06-01

185

A chemical waveform synthesizer.  

Science.gov (United States)

Algorithms and methods were developed to synthesize complex chemical waveforms in open volumes by using a scanning-probe microfluidic platform. Time-dependent variations and oscillations of one or several chemical species around the scanning probe, such as formation of sine waves, damped oscillations, and generation of more complex patterns, are demonstrated. Furthermore, we show that intricate bursting and chaotic calcium oscillations found in biological microdomains can be reproduced and that a biological cell can be used as a probe to study receptor functionalities as a function of exposure to time-dependent variations of receptor activators and inhibitors. Thus, the method allows for studies of biologically important oscillatory reactions. More generally, the system allows for detailed studies of complex time-varying chemical and physical phenomena in solution or at solution/surface interfaces. PMID:15928088

Olofsson, Jessica; Bridle, Helen; Sinclair, Jon; Granfeldt, Daniel; Sahlin, Eskil; Orwar, Owe

2005-05-31

186

Method for synthesizing HMX  

Energy Technology Data Exchange (ETDEWEB)

A method and apparatus for electrochemically synthesizing N.sub.2 O.sub.5 cludes oxidizing a solution of N.sub.2 O.sub.4 /HNO.sub.3 at an anode, while maintaining a controlled potential between the N.sub.2 O.sub.4 /HNO.sub.3 solution and the anode. A potential of about 1.35 to 2.0 V vs. SCE is preferred, while a potential of about 1.80 V vs. SCE is most preferred. Thereafter, the N.sub.2 O.sub.5 is reacted with either 1.5-diacetyl-3,7-dinitro-1,3,5,7-tetraazacyclooctane (DADN) or 1,3,5,7-tetraacetyl-1,3,5,7-tetraazacyclooctane (TAT) to form cyclotetramethylenetetraamine (HMX).

McGuire, Raymond R. (Brentwood, CA); Coon, Clifford L. (Fremont, CA); Harrar, Jackson E. (Castro Valley, CA); Pearson, Richard K. (Pleasanton, CA)

1984-01-01

187

Method for synthesizing finasteride  

UK PubMed Central (United Kingdom)

The invention provides a method for synthesizing finasteride. The method comprises the following steps: (1) dissolving trifluoroacetamide in solvent, reacting the solvent with trimethylchlorosilane in the presence of organic alkali or inorganic alkali, filtering out solid from reaction products, and collecting filtrate and (2) dissolving the filtrate obtained in step (1) in the solvent, adding 3-carbonyl-4-aza-5 alpha-androstane-17 belta-tert-butylformamide and dehydrogenation agent into the solvent for reaction, and collecting target products from reaction products. The method has the advantages that the method has higher yield, high selectivity, and is simple and safe after simple purification, the purity of the finasteride can reach more than 99 percent moreover, the method has easily obtained reagents used in the whole reaction, simultaneously having high reaction yield and mild reaction conditions, reclaiming the solvent and facilitating the industrialized production.

XIRONG LIU; LAIBIN XIE; AIGUO HU

188

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

Science.gov (United States)

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.

Tümer, Yasemin; Asmafiliz, Nuran; K?l?ç, Zeynel; Hökelek, Tuncer; Yasemin Koç, L.; Aç?k, Leyla; Yola, Mehmet Lütfi; Solak, Ali Osman; Öner, Ya?mur; Dündar, Devrim; Yavuz, Makbule

2013-10-01

189

Molecular modeling of the pendant chain in Nafion{reg_sign}  

Energy Technology Data Exchange (ETDEWEB)

Ion transport through perfluorosulfonic acid ionomers such as Nafion{reg_sign} is controlled by both the microstructure of the polymer and the charge and water distribution in the hydrated polymer. The authors present here the results of theoretical calculations on the side chain of Nafion{reg_sign}, establishing microscopic information for the modeling of water modeling of water modeling of water and proton transport in the membrane. Optimized geometries for the trifluoromethane sulfonic acid fragment (CF{sub 3}SO{sub 3}H), the di-trifluoromethane ether fragment (CF{sub 3}OCF{sub 3}), and the side chain (CF{sub 3}{single_bond}OCF{sub 2}CF(CF{sub 3})OCF{sub 2}CF{sub 2}SO{sub 3}H) were determined by means of both ab initio Hartree Fock theory with second order Moeller-Plesset electron correlation corrections, and density functional theory with Becke`s three parameter hybrid method. Several rotational potential energy surfaces were calculated to assess chain flexibility and proton accessibility. A probe water molecule was added to each of the fragments to characterize hydrophilic sites. These calculations confirmed that the sulfonic acid group is hydrophilic and the ethers are hydrophobic. Molecular dynamics simulations were then performed on the side chain to check the conditions required to stretch the pendant chain. Thermal averages of several structural parameters assessing the flexibility and stretch of the chain were computed from selected conformations produced in the simulation and these results indicate that although the sulfonate group is free to rotate, the chain stretches little. The construction of a potential energy surface for rotation about the second ether group suggests that the side chain exists in a folded or curled up conformation. A physical continuum dielectric solvent model was used to obtain free energies of electrostatic interaction of the fragments and the full chain with the solvent.

Paddison, S.J.; Zawodzinski, T.A.

1998-03-01

190

Polythiophene derivative comprising carbazoles as pendant groups for polymer solar cell applications  

International Nuclear Information System (INIS)

We have prepared a polythiophene copolymer (CzPh-PT) containing 9-position substituted carbazoles as bulky pendants and investigated its application in polymer solar cell (PSC). Electrochemical study presented that the onset oxidation potential positively shifted 0.47 eV for CzPh-PT in comparison with that of poly(3-hexyl thiophene). By incorporating the bulky substituent of CzPh-PT, the effective conjugation length can be curtailed, and consequently a lowered HOMO energy level (-5.38 eV) was acquired. This promises better air stability and a high open circuit voltage (Voc) for the PSC. Moreover, the optical properties of CzPh-PT reveal that the presence of ?-? interaction between carbazole units can enhance light harvesting ability in visible region, leading to a wide absorbance. PSC was fabricated based on an interpenetrating network of CzPh-PT as electron-sufficient polymer and [6,6]-phenyl C61 butyric acid methyl ester (PC61BM) as electron-deficient material. The PSC device based on the blend of CzPh-PT/PC61BM (w/w = 1:1) gave the best preliminary result with a Voc of 0.85 V, a short-circuit current of 1.57 mA/cm2, and a fill factor of 0.27, offering an overall power conversion efficiency of 0.36%. Our finding suggests that the polythiophene derivative comprising bulky steric groups as side chains is promising for PSC applications.

2011-05-31

191

Swinging Spiral Arms  

CERN Document Server

We study transient spiral structures in an isothermal, thin, galactic disc. We find no instability that can grow everywhere from infinitesimal disturbances, but spiral structure does grow in the disc due to an arbitrarily strong, asymmetric, central source. An initially finite spiral undergoes transient swing amplification as it is gradually wound-up by differential rotation. An independent sequence in negative time describes a leading spiral swinging to a trailing spiral. The dynamical coupling is established between the swinging potential and the arm particles, by ensuring that this potential constrains a locally rotating distribution function centred on the arms. This swing amplification propagates in radius at the constant rotational speed of the disc, and leaves behind an exponential density decline in space and time.

Henriksen, Richard N

2012-01-01

192

Robot arm apparatus  

Energy Technology Data Exchange (ETDEWEB)

A robot arm apparatus is provided for inspecting and/or maintaining an interior of a steam generator which has an outside wall and a port for accessing the interior of the steam generator. The robot arm apparatus includes a flexible movable conduit for conveying inspection and/or maintenance apparatus from outside the steam generator to the interior of the steam generator. The flexible conduit has a terminal working end which is translated into and around the interior of the steam generator. Three motors located outside the steam generator are employed for moving the terminal working end inside the steam generator in ``x,`` ``y,`` and ``z`` directions, respectively. Commonly conducted inspection and maintenance operations include visual inspection for damaged areas, water jet lancing for cleaning sludge deposits, core boring for obtaining sludge deposits, and scrubbing of internal parts.

Nachbar, H.D.

1990-12-31

193

Microelectromechanical safe arm device  

Energy Technology Data Exchange (ETDEWEB)

Microelectromechanical (MEM) apparatus and methods for operating, for preventing unintentional detonation of energetic components comprising pyrotechnic and explosive materials, such as air bag deployment systems, munitions and pyrotechnics. The MEM apparatus comprises an interrupting member that can be moved to block (interrupt) or complete (uninterrupt) an explosive train that is part of an energetic component. One or more latching members are provided that engage and prevent the movement of the interrupting member, until the one or more latching members are disengaged from the interrupting member. The MEM apparatus can be utilized as a safe and arm device (SAD) and electronic safe and arm device (ESAD) in preventing unintentional detonations. Methods for operating the MEM apparatus include independently applying drive signals to the actuators coupled to the latching members, and an actuator coupled to the interrupting member.

Roesler, Alexander W. (Tijeras, NM)

2012-06-05

194

Robot arm apparatus  

Energy Technology Data Exchange (ETDEWEB)

A robot arm apparatus is provided for inspecting and/or maintaining an interior of a steam generator which has an outside wall and a port for accessing the interior of the steam generator. The robot arm apparatus includes a flexible movable conduit for conveying inspection and/or maintenance apparatus from outside the steam generator to the interior of the steam generator. The flexible conduit has a terminal working end which is translated into and around the interior of the steam generator. Three motors located outside the steam generator are employed for moving the terminal working end inside the steam generator in "x", "y", and "z" directions, respectively. Commonly conducted inspection and maintenance operations include visual inspection for damaged areas, water jet lancing for cleaning sludge deposits, core boring for obtaining sludge deposits, and scrubbing of internal parts.

Nachbar, Henry D. (Ballston Lake, NY)

1992-01-01

195

Worldwide report, arms control  

Energy Technology Data Exchange (ETDEWEB)

This report contains translations/transcriptions of articles and/or broadcasts about Arms Control. Titles include: USSR: Strategic, Historical, Economic Critique of SDI; FRG Foreign Minister Comments on Eureka Projects; Moscow Daily Interviews Scottish Professor on SDI, SALT, INF; FRG Paper Calls U.S. Abrogation of SALT II Unjustified; Australia, New Zealand Agree to Monitor Tests; FRG Press Comments on NATO Foreign Ministers Meeting; PRC Liberation Army Daily Analyzes Prospects for World Peace; and others.

NONE

1987-02-27

196

Cutting arm. Bras haveur  

Energy Technology Data Exchange (ETDEWEB)

According to the invention, notches are arranged along the peripheries of the drive wheel and return wheel of a cutting arm, the notches being separated from one another by crests. This arrangement makes it possible to transmit the torque to the endless element, whose outside is fitted with cutting tools and whose inside is laced with guide blocks, by the totality of the fibres adjacent to the main fibres of the endless element and not by the guide blocks.

Hallez, C.P.

1988-09-28

197

Small arms ammunition  

Energy Technology Data Exchange (ETDEWEB)

An elongate projectile for small arms use has a single unitary mass with a hollow nose cavity defined by a sharp rigid cutting edge adapted to make initial contact with the target surface and cut therethrough. The projectile then enters the target mass in an unstable flight mode. The projectile base is substantially solid such that the nose cavity, while relatively deep, does not extend entirely through the base and the projectile center of gravity is aft of its geometric center.

Huerta, Joseph (399 Clover St., Aberdeen, MD 21001)

1992-01-01

198

Sdi and arms control  

Energy Technology Data Exchange (ETDEWEB)

President Reagan's Strategic Defense Initiative, or SDI, and the pursuit of defenses to protect against ballistic missile attack are issues of significant debate. Some praise the proposal, first made in a presidential address to the nation on 23 March 1983, as a grand vision that will abolish nuclear blackmail by adopting a totally defensive posture. Others condemn it as being destabilizing, a Pandora's box of strategic transition that could precipitate armed conflict.

DeWolf, H.G.

1989-11-01

199

Method for synthesizing famciclovir  

UK PubMed Central (United Kingdom)

The invention relates to a method for synthesizing famciclovir, which includes preparing sodium salt of diethyl malonate at the acting of sodium ethylate by taking diethyl malonate as raw charge and ethyl hydrate as dissolvent, preparing bromo ethyl group diethyl malonate by carrying out nucleophilic substitution reaction with 1, 2-dibromoethane and sodium salt of diethyl malonate, preparing bromo ethyl group propanediol by deoxidizing bromo ethyl group diethyl malonate at the acting of sodium borohydride, preparing 2-acetyl oxygen radicel methyl radicel -4-bromo butyl acetic ester by carrying out reaction with bromo ethyl group propanediol and acylating agent acetic oxide, preparing 2-(2-acetyl oxygen radicel-4-bromo butyl acetic ester)-6-chloropurine by carrying out condensation with 2-acetyl oxygen radicel methyl radical-4-bromo butyl acetic ester and 2-amidocyanogen-6-chloropurine, and then preparing famciclovir by carrying out dechlorination with 2-(2-acetyl oxygen radicel methyl radical -4-bromo butyl acetic ester)-6-chloropurine. This method is suitable for the industrial production with short production line, high yield and low cost.

YANG PENG

200

Technique for synthesizing vitacampher  

UK PubMed Central (United Kingdom)

The invention discloses a process for synthesizing oxocamphor. The process comprises the steps of dissolving camphor in chloroform, adding bromine for completing bromination, obtaining pi-acetyloxaphor through esterification and reduction, adding potassium hydroxide and ethanol for hydrolysis, extracting through chloroform, adding solvent oil for crystallization, dissolving crystals in water, adding sulfuric acid and the like for oxidation, performing addition after neutralization, adding aether for extraction to obtain oxocamphor addition liquid, adding sodium carbonate for decomposition reaction, using aether for extraction to obtain oxocamphor aether liquid, sequentially performing concentration, alkali washing, water washing, dehydration and decoloration, and obtaining the oxocamphor. The process has the advantages of substituting bromination reaction for chlorine reaction, changing gaseous reaction, realizing liquid reaction, lowering risk, reducing reaction steps, using copper acetate substituted zinc powder as a reducing agent, lowering risk and raising product yield. As an end product is purified through extraction, decomposition and re-extraction after salt formation, the purity of the product is improved and reaches the current injection standard that the purity is higher than 99 percent in China.

DAWEI GUAN; PEIGE DU; YUFENG SUN; SHUANG JIANG

 
 
 
 
201

Reduced-impact logging effects on commercial non-vascular pendant epiphyte biomass in a tropical montane forest in Costa Rica.  

UK PubMed Central (United Kingdom)

Compatibility of different commercial uses of a montane tropical oak–bamboo forest in Costa Rica was assessed for selective logging and harvesting of non-vascular pendant epiphytes, a locally valuable non-timber forest product (NTFP). The non-vascular pendant epiphyte taxa examined were mosses (Pilotrichella flexilis, Phyllogonium viscosum, Zelometeorium sp., Squamidium leucotrichum); liverworts (Frullania convoluta and Frullania spp.); and lichens (Usnea spp.). All of these species have pendant life-forms, and apparently play key roles in water interception, thereby influencing the hydrological balance in tropical montane ecosystems. Since the growth of pendant non-vascular epiphytes conversely depends on fog and mist, these species could be used as indicators of health of the tropical montane forests where they abound. Nine years after careful selective logging, no negative impacts were detected on the biomass of these NTFPs at the heights at which they are commercially harvested (1–3 m). This result was established through comparisons of logged and non-logged plots on the basis of abundance (biomass) of the commercial bryophytes and related variables such as substrate length availability and substrate type (shade tolerant, pioneer species, or bamboo, and substrate diameter). Pendant epiphytes were most abundant on thin substrates (branches <1 cm in diameter); the highest biomass values per unit substrate length were found on branches of shade-tolerant species.

Romero C

1999-06-01

202

Inorganic syntheses reagents for transition metal complex and organometallic syntheses  

CERN Document Server

The volumes in this continuing series provide a compilation of current techniques and ideas in inorganic synthetic chemistry. Includes inorganic polymer syntheses and preparation of important inorganic solids, syntheses used in the development of pharmacologically active inorganic compounds, small-molecule coordination complexes, and related compounds. Also contains valuable information on transition organometallic compounds including species with metal-metal cluster molecules. All syntheses presented here have been tested.

Angelici, Robert J

2009-01-01

203

Electromyographic investigation of hypnotic arm levitation: differences between voluntary arm elevation and involuntary arm levitation.  

UK PubMed Central (United Kingdom)

Thirty-three volunteers were randomly exposed to 3 conditions: hypnotic arm levitation, holding up the arm voluntarily without hypnosis, and imagined arm lifting without hypnosis. Trapezius, deltoid, extensor digitorum, flexor digitorum profundus, biceps brachii, and triceps brachii muscles were measured. Strain and muscle activity during lifting and holding up the right arm for 3 minutes were used as dependent variables. During hypnotic arm levitation, the total muscle activity was lower than during holding it up voluntarily (p < .01); the activity in the deltoid was 27% lower (p < .001). Without hypnosis, the muscle activity showed a positive correlation with strain. However, there was no such correlation in the hypnotic condition. Apparently, it is possible to reduce strain and to objectively measure muscle activity in an uplifted arm through hypnotic arm levitation.

Peter B; Schiebler P; Piesbergen C; Hagl M

2012-01-01

204

MARS--multiple automated robotic synthesizer for continuous flow of peptides.  

Science.gov (United States)

We have designed and constructed a multiple automated robotic synthesizer, the MARS. Its novel timing procedure for handling multiple synthetic tasks eliminates unnecessary respite time by keeping the robotic arm in continuous operation. Polypropylene syringes equipped at the bottom with polypropylene frits serve as physically independent reaction vessels. All operations are performed by the robotic arm, which is equipped with a specially designed gripper to hold a syringe and to aspirate and dispense liquid. Typically, the MARS synthesizes concurrently 5 to 15 peptides of different length, and once one peptide is finished it automatically starts the synthesis of the next peptide in the queue, assuring a continuous flow of peptides. PMID:8727483

Krchnák, V; Cabel, D; Lebl, M

205

Liquid-vapour surface tension measurements of refractory metals by the pendant drop method under ultrahigh vacuum conditions  

International Nuclear Information System (INIS)

A careful implementation of the pendant drop technique for preparing the samples processed in an ultrahigh vacuum drop tube allows to measure accurately the liquid-vapor surface tension of a new set of refractory metals (Hf, V, Ti). It is shown that the result value disparity is essentially due to the complex action of the gases that are present in the drop volume. This study may also help to understand the significant disparities observed between the published values of this property. (authors). 12 refs., 1 fig., 2 tabs.

1994-01-01

206

Hyper-efficient quenching of non-conjugated pendant polymer by silver nanoparticles: A demonstration and versatile mechanistic proposition  

Science.gov (United States)

Hyper-efficient quenching of fluorescence of non-conjugated polymer poly(N-vinylcarbazole) by silver nanoparticles is demonstrated. The quenching efficiency increases with an increase in the length of the polymer chain containing the pendant chromophore units. The Stern-Volmer constants (109-1010 mol-1 dm3) are found to be orders of magnitude higher than the normal photochemical quenching processes. Although nanoparticle induced hyper-quenching is reported for conjugated polymers, similar observation in non-conjugated polymers is unprecedented. A versatile mechanism is proposed that rationalizes the hyper-quenching of both conjugated and non-conjugated polymers.

Ghosh, Debanjana; Chattopadhyay, Nitin

2012-04-01

207

Triarylphosphine Ligands with Pendant Electron-Rich "[Fe(?(2)-dppe)(?(5)-C5Me5)(C?C)]-" Substituents.  

UK PubMed Central (United Kingdom)

The synthesis of four triaylphosphine ligands featuring electron-rich Fe(II) "Fe(?(2)-dppe)(?(5)-C5Me5)C?C-" pendant substituents in para and meta position(s) (1-4) is reported along with that of their corresponding radical cations (1-2[PF6] or 3-4[PF6]3). These triarylphosphines possessing redox-active organometallic substituents constitute a new class of phosphorus-based metallo-ligands. In contrast to many related ferrocenylphosphines, these metallo-ligands are stable and isolable in two redox-states. Their steric and electronic properties are also briefly discussed.

Tohmé A; Grelaud G; Argouarch G; Roisnel T; Bondon A; Paul F

2013-08-01

208

Arms race modeling: systematic analysis and synthesis. (Volumes I and II)  

Energy Technology Data Exchange (ETDEWEB)

In recent years there has been a significant proliferation of arms race models in journals and books across many disciplines. Numerous factors have been put forth as relevant by arms race modelers and diverse analytical and explanatory approaches have been employed. This indicates that arms race modeling can be advanced by a systematic analysis (review) and synthesis. This is the purpose of this thesis). Part I discusses the perspective, purposes, and organization of this thesis, definitions of arms race, and mathematical modeling as a tool of arms race research. Parts II-VI review in detail over 125 arms race models and numerous other defense determination models. Part VII synthesizes arms race modeling factors and approaches from the perspective of economics. Each side in an arms race is viewed as facing an economic choice problem of how to allocate scarce resources between defense and nondefense goods. Part VIII undertakes policy analysis using the models developed in Part VII. The three issues investigated are (1) nuclear-conventional substitutability in the European theater, (2) the Strategic Defense Initiative, and (3) the impact of arms races on outputs and factor rewards. Part IX discusses future research avenues related to arms race modeling.

Anderton, C.H.

1986-01-01

209

H-1 NMR relaxivity of aqueous suspensions of titanium dioxide nanoparticles coated with a gadolinium(III) chelate of a DOTA-monoamide with a phenylphosphonate pendant arm  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A new efficient and easy method to anchor Gd(III) chelates onto a TiO2 surface in order to prepare a nanoparticulate T-1 MRI contrast agent is reported. For this purpose, a new ligand, DOTAPP, a DOTA-monoamide derivative containing a phenylphosphonic acid function in the amide side chain, was synthe...

Rehor, I.; Kubicek, V.; Kotek, J.; Hermann, P.; Lukes, I.; Szakova, J.; Vander Elst, Luce; Muller, Robert; Peters, J. A.

210

Investigation on Al(III) and Zn(II) complexes containing a calix[4]arene bearing two 8-oxyquinoline pendant arms used as emitting materials for OLEDs  

International Nuclear Information System (INIS)

A comparison between [Al?1]3+ and [Zn?1]2+ complexes (1 = 5,11,17,23-tetra-tert-butyl-25,27-bis[(quinoline-8-oxy)propyloxy]-26, 28-dihydroxy-calix[4]arene) has been made using electrochemical techniques and the experimental results obtained in the fabrication of organic light emitting devices (OLEDs). The electrochemically determined values of the ionization potential Ip and electron affinity Ea parameters for the [Al?1]3+ (Ip = 5.82eV, Ea = 2.80eV) and [Zn?1]2+ (Ip = 5.67eV, Ea = 2.32eV) evidenced that the [Al?1]3+ complex is a better electron transporting layer with respect to the Zn complex one. The fabricated OLEDs based on these supramolecular complexes show a superior quality with the [Al?1]3+ systems expected from the energy level diagrams.

2009-01-01

211

Light duty utility arm  

Energy Technology Data Exchange (ETDEWEB)

The Light-Duty Utility Arm (LDUA) System is a mobile, multi-axis positioning system capable of deploying tools and sensors (end effecters) inside radioactive waste tanks for tank wall inspection, waste characterization, and waste retrieval. The LDUA robotic manipulator enters a tank through existing openings (risers) in the tank dome of the underground tanks. Using various end effecters, the LDUA System is a versatile system for high-level waste tank remediation. The LDUA System provides a means to deploy tools, while increasing the technology resources available to the U.S. Department of Energy (DOE). Ongoing end effecter development will provide additional capabilities to remediate the waste tanks.

NONE

1998-12-01

212

Internal combustion engine rocker arm  

Energy Technology Data Exchange (ETDEWEB)

This patent describes an internal combustion engine cylinder head exhaust valve operating elongated rocker arm having a friction reducing valve stem end contacting roller journalled by a bolt extending through a transverse bore in one end portion of the rocker arm normal to the axis of the valve stem. The improvement comprises: means for adjusting the position of the roller longitudinally of the rocker arm and relative to the axis of the exhaust valve stem.

Craig, J.A.

1987-09-22

213

Build Your Own Robot Arm  

Science.gov (United States)

In this lesson, learners develop a robot arm using common materials. Learners explore design, construction, and teamwork, as well as materials selection and use. The robot arm must be at least 18 inches in length and must be able to pick up an empty Styrofoam cup. Teams of learners must agree on a design for the robot arm and identify what materials will be used. Learners will draw a sketch of their design prior to construction. Resulting robot arms are then tested and checked for range of motion and satisfaction of the given criteria.

Ieee

2012-01-01

214

Pulsars as spiral arm tracers  

Energy Technology Data Exchange (ETDEWEB)

Pulsars are used to trace the spiral arms of the Galaxy. Present pulsar characteristics are used to divide them into two pulsar types as defined by Huang (1987). The ages of Type II pulsars and the galactic rotation curve are used to determine their position at birth. The spiral arm pattern velocity is used to reconstruct the arms from which the individual Type II pulsars originated. It is found that the best fit to the data requires spiral arm segments with a pitch angle of 14.5 deg. 25 refs.

Morgan, S. (Washington Univ., Seattle (USA))

1990-01-01

215

Synthesis and photochemical properties of a novel iron-sulfur-nitrosyl cluster derivatized with the pendant chromophore protoporphyrin IX.  

UK PubMed Central (United Kingdom)

The novel Roussin red-salt ester (PPIX-RSE) with a pendant porphyrin chromophore was prepared and investigated as a precursor for the photochemical generation of nitric oxide. PPIX-RSE has the general formula Fe(2)(NO)(4)[(mu-S,mu-S')P] (where (S,S')P is the bis(2-thiolatoethyl) diester of protoporphyrin IX. The photoexcitation of PPIX-RSE with 436- or 546-nm light in an aerated chloroform solution led to the photodecomposition of the cluster with the respective quantum yields (5.2 +/- 0.7) x 10(-4) and (2.5 +/- 0.5 x 10(-4)) and the concomitant release of NO. PPIX-RSE is a significantly more effective NO generator at longer wavelength excitation than are other Fe(2)(mu-SR)(2)(NO)(4) esters for which R is a simple alkyl group such as CH(3)CH(2)- because of the much higher absorptivity of the pendant PPIX chromophore at these wavelengths and a modestly higher quantum yield. Fluorescence intensity and lifetime data indicate that the photoexcited porphyrin of PPIX-RSE is largely quenched by the energy transfer to the Fe(2)S(2)(NO)(4) cluster's core. However, a small fraction of this emission is not quenched, and it is proposed that PPIX-RSE may exist in solution as two conformers.

Conrado CL; Wecksler S; Egler C; Magde D; Ford PC

2004-09-01

216

X-Armed Bandits  

CERN Document Server

We consider a generalization of stochastic bandits where the set of arms, $\\cX$, is allowed to be a generic measurable space and the mean-payoff function is "locally Lipschitz" with respect to a dissimilarity function that is known to the decision maker. Under this condition we construct an arm selection policy, called HOO hierarchical optimistic optimization), with improved regret bounds compared to previous results for a large class of problems. In particular, our results imply that if $\\cX$ is the unit hypercube in a Euclidean space and the mean-payoff function has a finite number of global maxima around which the behavior of the function is locally H\\"older continuous with a known exponent, then the expected of HOO regret is bounded up to a logarithmic factor by $\\sqrt{n}$, i.e., the rate of growth of the regret is independent of the dimension of the space. We also prove the minimax optimality of our algorithm when the dissimilarity is a metric.

Bubeck, Sébastien; Stoltz, Gilles; Szepesvari, Csaba

2010-01-01

217

A cyclopalladated complex of corannulene with a pyridine pendant and its columnar self-assembly.  

UK PubMed Central (United Kingdom)

Bowl-shaped corannulene provides various metal binding modes with its curved ?-surfaces and rim. Herein, we report the syntheses of 2-pyridylcorannulene and its cyclopalladated complex. Its expanded ?-system and columnar self-assembly in the crystal state were revealed by NMR and UV-vis spectroscopies, ESI-TOF mass spectrometry and single-crystal X-ray analysis.

Yamada M; Tashiro S; Miyake R; Shionoya M

2013-03-01

218

A modular synthesis of dithiocarbamate pendant unnatural α-amino acids  

Science.gov (United States)

Unnatural α-amino acids containing dithiocarbamate side chains were synthesized by a one-pot reaction of in-situ generated dithiocarbamate anions with sulfamidates. A wide range of these anions participated in the highly regio- and stereo-selective ring opening of sulfamidates to...

219

Synthesis and photophysical properties of new chromium(III) complexes of N-derivatized 1,4,8,11-tetraazacyclotetradecane ligands cis-[Cr(1,8-R(2)cyclam)Cl(2)]Cl, where R is a pendant chromophore. exclusive formation of the cis isomer.  

UK PubMed Central (United Kingdom)

Several new chromium(III) complexes have been synthesized utilizing derivatives of the macrocyclic ligand cyclam (1,4,8,11-tetraazacyclotetradecane) with various N-substituted chromophores in the 1 and 8 positions (1,8-R(2)cyclam) where R = CH(3), CH(2)Ph, CH(2)Nph (Nph = naphthyl), and CH(2)Anth (Anth = anthracyl). X-ray crystal structures were determined for all four complexes, and these are formed exclusively in the cis configuration with the two tertiary amines in the "hinge" positions (i.e., along the folding axis) of the coordinated ligand. As a result, the cis isomers appear to be inert to isomerization under conditions dramatically more forcing than needed to effect the cis to trans isomerization of the unsubstituted Cr(cyclam)Cl(2)(+) ion. Photophysical studies demonstrated that emission occurs solely from the metal-centered ligand field doublet excited states regardless of whether initial excitation is into the quartet ligand field bands or into the pi-pi bands of the pendant chromophore. Thus, excitation of the pendant chromophore results in efficient intramolecular energy transfer to the metal centered ligand field excited states.

DeRosa F; Bu X; Ford PC

2003-06-01

220

Farming with an Arm Amputation  

Science.gov (United States)

Farming with an Arm Amputation Farmers with upper-extremity amputations are at risk of secondary injuries because they may (a) have decreased padding ... crops, livestock, or equipment, (c) use the noneffected arm or hand to break a fall or perform ...

 
 
 
 
221

Rocker arm support assembly  

Energy Technology Data Exchange (ETDEWEB)

A support assembly is described for mounting at least one rocker arm rotatably journaled on a cylindrical shaft on an internal combustion engine. The assembly is for operating a valve connected with an engine cylinder in response to actuation by a push rod and an engine cylinder head having a locating means for accurately positioning the support assembly relative to the engine valves. The support assembly comprises: (a) pedestal means for engaging the shaft and securing the shaft to the engine head; and (b) pedestal positioning means located on the pedestal means to extend downwardly therefrom for positively engaging the corresponding location means of the head for positioning the pedestal means so that the shaft is in substantial alignment with the longitudinal axis of the cylinder head.

Wells, L.; Baugh, J.D.

1987-04-07

222

ARM SUPPORT APPARATUS  

UK PubMed Central (United Kingdom)

Arm support apparatus with a support body including elbow, forearm and wri st supports, a front portion located away from a torso of a user and a rear portion disposed towards the torso. The apparatus includes a first front portion connector connected to the front portion and a first rear portion connector connected to the rear portion, each are located towards the wrist support. A second front portion connector is connected to the front portion and spaced apart from the first front portion connector, and is located towards the elb ow support. A wrist end connector is connected to the support and located towar ds the wrist support. A first shoulder strap has strap ends, each being connect ed respectively to the front and rear connectors. A second shoulder strap has strap ends, one being connected to the second front portion connector, the other being connected to the wrist end connector member.

AVON GUY

223

The Neanderthal lower arm.  

Science.gov (United States)

Neanderthal forearms have been described as being very powerful. Different individual features in the lower arm bones have been described to distinguish Neanderthals from modern humans. In this study, the overall morphology of the radius and ulna is considered, and morphological differences among Neanderthals, Upper Paleolithic Homo sapiens and recent H. sapiens are described. Comparisons among populations were made using a combination of 3D geometric morphometrics and standard multivariate methods. Comparative material included all available complete radii and ulnae from Neanderthals, early H. sapiens and archaeological and recent human populations, representing a wide geographical and lifestyle range. There are few differences among the populations when features are considered individually. Neanderthals and early H. sapiens fell within the range of modern human variation. When the suite of measurements and shapes were analyzed, differences and similarities became apparent. The Neanderthal radius is more laterally curved, has a more medially placed radial tuberosity, a longer radial neck, a more antero-posteriorly ovoid head and a well-developed proximal interosseous crest. The Neanderthal ulna has a more anterior facing trochlear notch, a lower M. brachialis insertion, larger relative mid-shaft size and a more medio-lateral and antero-posterior sinusoidal shaft. The Neanderthal lower arm morphology reflects a strong cold-adapted short forearm. The forearms of H. sapiens are less powerful in pronation and supination. Many differences between Neanderthals and H. sapiens can be explained as a secondary consequence of the hyper-polar body proportions of the Neanderthals, but also as retentions of the primitive condition of other hominoids. PMID:21762953

De Groote, Isabelle

2011-07-16

224

The Neanderthal lower arm.  

UK PubMed Central (United Kingdom)

Neanderthal forearms have been described as being very powerful. Different individual features in the lower arm bones have been described to distinguish Neanderthals from modern humans. In this study, the overall morphology of the radius and ulna is considered, and morphological differences among Neanderthals, Upper Paleolithic Homo sapiens and recent H. sapiens are described. Comparisons among populations were made using a combination of 3D geometric morphometrics and standard multivariate methods. Comparative material included all available complete radii and ulnae from Neanderthals, early H. sapiens and archaeological and recent human populations, representing a wide geographical and lifestyle range. There are few differences among the populations when features are considered individually. Neanderthals and early H. sapiens fell within the range of modern human variation. When the suite of measurements and shapes were analyzed, differences and similarities became apparent. The Neanderthal radius is more laterally curved, has a more medially placed radial tuberosity, a longer radial neck, a more antero-posteriorly ovoid head and a well-developed proximal interosseous crest. The Neanderthal ulna has a more anterior facing trochlear notch, a lower M. brachialis insertion, larger relative mid-shaft size and a more medio-lateral and antero-posterior sinusoidal shaft. The Neanderthal lower arm morphology reflects a strong cold-adapted short forearm. The forearms of H. sapiens are less powerful in pronation and supination. Many differences between Neanderthals and H. sapiens can be explained as a secondary consequence of the hyper-polar body proportions of the Neanderthals, but also as retentions of the primitive condition of other hominoids.

De Groote I

2011-10-01

225

Anionic polymerization and polyhomologation: an ideal combination to synthesize polyethylene-based block copolymers.  

UK PubMed Central (United Kingdom)

A novel one-pot methodology combining anionic polymerization and polyhomologation, through a "bridge" molecule (BF3OEt2), was developed for the synthesis of polyethylene (PE)-based block copolymers. The anionically synthesized macroanion reacts with the "bridge" molecule to afford a 3-arm star (trimacromolecular borane) which serves as an initiator for the polyhomologation.

Zhang H; Alkayal N; Gnanou Y; Hadjichristidis N

2013-09-01

226

Anionic polymerization and polyhomologation: an ideal combination to synthesize polyethylene-based block copolymers.  

Science.gov (United States)

A novel one-pot methodology combining anionic polymerization and polyhomologation, through a "bridge" molecule (BF3OEt2), was developed for the synthesis of polyethylene (PE)-based block copolymers. The anionically synthesized macroanion reacts with the "bridge" molecule to afford a 3-arm star (trimacromolecular borane) which serves as an initiator for the polyhomologation. PMID:23963373

Zhang, Hefeng; Alkayal, Nazeeha; Gnanou, Yves; Hadjichristidis, Nikos

2013-09-10

227

Worldwide report: Arms control, [April 22, 1987  

Energy Technology Data Exchange (ETDEWEB)

This document contains articles on arms control throughout the world. Some topics discussed include strategic defense initiative, space arms, US-USSR nuclear and space arms talks, intermediate-range nuclear forces, chemical and biological weapons, and nuclear testing.

NONE

1987-04-22

228

After Arizona: Military Musicians in the Second World War Après Arizona: les musiciens dans la marine américaine pendant la Seconde Guerre mondiale  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Cet article traite du rôle des musiciens dans la marine américaine pendant la Seconde Guerre mondiale. L’histoire de l’USS Arizona — et de son orchestre, noyé avec le cuirassé lors de l’attaque surprise des forces japonaises — étant bien connue, je m’appuie sur cet exemple comme point de départ afin...

Rosemary Peters

229

Corrections to the article "The metric dimension of graph with pendant edges" [Journal of Combinatorial Mathematics and Combinatorial Computing, 65 (2008) 139--145  

CERN Multimedia

We show that the principal results of the article "The metric dimension of graph with pendant edges" [Journal of Combinatorial Mathematics and Combinatorial Computing, 65 (2008) 139--145] do not hold. In this paper we correct the results and we solve two open problems described in the above mentioned paper.

Kuziak, D; Yero, I G

2010-01-01

230

Battery saving frequency synthesizer arrangement  

Energy Technology Data Exchange (ETDEWEB)

An arrangement for reducing the amount of battery supplied power to a high frequency synthesizer. The phase-locked loop section of the synthesizer is periodically disconnected from the battery supplied power. In order to prevent substantial drift of the phase-locked loop during such power interruption, a control signal is provided for maintaining the VCO frequency. By minimizing the frequency drift, the loop can be re-locked in a short period of time following each power interruption.

Challen, R. F.

1985-06-04

231

JPRS report: Arms control, [December 14, 1987  

Energy Technology Data Exchange (ETDEWEB)

This document contains articles about arms control throughout the world. Some topics discussed are strategic defense initiative, space arms, chemical and biological weapons, nuclear testing, security and treaties.

NONE

1987-12-14

232

JPRS report: Arms control, [September 18, 1987  

Energy Technology Data Exchange (ETDEWEB)

Topics include SDI, Space arms; Space arms talks; Intermediate-range nuclear forces; Chemical weapons; Biological weapons; European conferences; Nuclear testing and free zone proposals; and related issues.

NONE

1987-09-18

233

La evolución de la relación salarial durante la post convertibilidad L’évolution du rapport salarial pendant la post-convertibilité The evolution of the labor-wage nexus during the post-convertibility phase  

Directory of Open Access Journals (Sweden)

Full Text Available Este capítulo constituye una síntesis de trabajos realizados conjuntamente con Robert Boyer durante la década pasada y tiene como objetivo mostrar los cambios y la evolución de la relación salarial durante el periodo de la post-convertibilidad, es decir desde 2002 hasta fines de 2011, así como las principales restricciones que debe enfrentar el nuevo modo de desarrollo desde la crisis de los subprimes, que se manifiestan con fuerza desde el inicio del Segundo Mandato de la Dra. Cristina Fernández de Kirchner.Ce chapitre est une synthèse des travaux réalisés pendant la décennie dernière. Il analyse les changements du rapport salarial après l'abandon de la convertibilité, c´est-à-dire depuis 2002 et jusqu´à la fin de 2011. Il explicite ensuite les principales contraintes qui s'imposent au nouveau mode de développement depuis la crise des subprimes et limitent sa viabilité. Ces tensions se manifestent avec force dès le début du deuxième mandat de la présidente Cristina Fernández de Kirchner.This contribution synthesizes a decade of research. It analyses the dynamics of the wage-labor nexus after the convertibility period, i.e. from 2002 until the end of 2011. It also scrutinizes the most salient constraints arising in the development mode after the subprime crisis that limit its viability. These problems are becoming more obvious since the beginning of President Cristina Fernández de Kirchner second term.

Julio César Neffa

2012-01-01

234

Histoire culturelle et linguistique des dictionnaires bilingues en Algérie pendant la période coloniale : 1830-1930  

Directory of Open Access Journals (Sweden)

Full Text Available Cet article décrit les dictionnaires bilingues composés en Algérie pendant la période coloniale (1830-1930) envisagés dans leur multidimensionnalité. Pour examiner ces outils linguistiques et culturels, nous avons opté pour une perspective alliant à la fois les avantages de la dimension historique, l’apport de la sociolinguistique et la dimension critique de la métalexicographie. La dimension historique tend à mettre au jour les circonstances d’apparition, de développement et de réception des dictionnaires bilingues dans le contexte colonial. Elle permet de restituer le contexte historique ainsi que les conditions sociétales de l’apparition des dictionnaires bilingues. L’approche sociolinguistique permet d’aborder la lexicographie bilingue coloniale dans l’ensemble des processus de production, de réception et de circulation sociale. Cette dimension enrichit la dimension proprement métalexicographique abordant les dictionnaires dans leur composante linguistique à travers une méthodologie éprouvée s’inscrivant dans la francophonie.

François Gaudin; Mahfoud Mahtout

2013-01-01

235

Nommer le conflit. Le cas de l’Alsace pendant son annexion de fait au Troisième Reich, 1940-1945  

Directory of Open Access Journals (Sweden)

Full Text Available L’étude des comportements et opinions de la population en Alsace entre 1940 et 1945 fait appel à la nécessité de nommer une conflictualité parfois floue, ambivalente et qui évolue au cours de la période. Il convient de s’interroger sur l’adaptation des outils de définition des comportements développés en France et en Allemagne pour la situation alsacienne pendant l’annexion de fait de son territoire.   Alsace 1940-1945, oppositions au nazisme, comportements collectifsDie Erforschung des Verhaltens und der Meinung der Bevölkerung im Elsass zwischen 1940-1945 bringt die Notwendigkeit mit sich, eine zuweilen undurchsichtige, zweideutige Konfliktträchtigkeit zu benennen, die sich im Zeitraum der Annektierung zudem entwickelte. Die methodischen Werkzeuge zur Definition kollektiven Verhaltens, die in Frankreich und Deutschland für diesen elsässischen Fall entwickelt wurden, müssen hierbei angepasst werden.

Anne-Ségolène Verneret

2011-01-01

236

Equilibrium shapes and stability of nonconducting pendant drops surrounded by a conducting fluid in an electric field  

Energy Technology Data Exchange (ETDEWEB)

The shapes and stability of pendant drops in the presence of an electric field is a classical problem in capillarity. This problem has been studied in great detail by numerous investigators when the drops are either perfect conductors or nonconductors and the surrounding fluid is a nonconductor. In this paper, the axisymmetric equilibrium shapes and stability of a nonconducting drop hanging from a nonconducting nozzle that is immersed in a perfectly conducting ambient fluid, a problem that has heretofore not been considered in the literature, are determined by solving the free boundary problem comprised of the Young-Laplace equation for drop shape and an integral equation for the electric field distribution. Here the free boundary problem is discretized by a hybrid technique in which the Young-Laplace equation is solved by the finite element method and the electrostatic problem solved by the boundary element method.

Harris, M.T.; Basaran, O.A. [Oak Ridge National Lab., TN (United States). Chemical Technology Division

1995-03-15

237

Les femmes et les enfants, prisonniers politiques ou déportés à titre préventif pendant la guerre civile grecque  

Directory of Open Access Journals (Sweden)

Full Text Available Les conditions et stratégies de survie des milliers de femmes condamnées ou déportées de la guerre civile grecque permettent d'établir une typologie.Pendant la guerre civile grecque (1946-1949) des milliers de personnes sont emprisonnées, déportées dans des camps de concentration ou exilées dans des îles, une population hétéroclite d’hommes et de femmes, persécutés pour leurs idées, leurs origines ou même des liens de parenté avec les communistes. Dans la présente étude, nous nous intéresserons à un groupe lui-même peu homogène, les femmes et les enfants, prisonniers politiques ou déportés à titre préventif pendant le conflit. Après un bref rappel de la pratique de la déportation et une esquisse de typologie de la réclusion, nous étudierons les conditions de détention et les stratégies de survie des femmes, souvent emprisonnées avec leurs enfants, leur statut au sein des prisonniers politiques ainsi que le sens de l'engagement politique dans leur système de valeurs.During the Greek Civil War (1946-1949) thousands of persons were imprisoned, deported to concentration camps or exiled on the islands, a heteroclite population of men and women, persecuted for their ideas, their origins or even their association with the Communists. In the present study, we are interested in a not particularly homogeneous group of women and children, political prisoners or deportees who had been detained for preventive reasons during the conflict. Following a brief summary of the practice of deportation and a typological sketch of the imprisonment, we shall study the detention conditions and the survival strategies of the women, often imprisoned with their children, their status vis-à-vis the political prisoners as well as the meaning of political commitment in their value system.

Christina Alexopoulos

2011-01-01

238

Introduction of bridging and pendant organic groups into mesoporous alumina materials.  

UK PubMed Central (United Kingdom)

Incorporation of organic functionalities into soft-templated mesoporous alumina was performed via organosilane-assisted evaporation induced self-assembly using aluminum alkoxide precursors and block copolymer templates. This strategy permits one to obtain mesoporous alumina-based materials with tailorable adsorption, surface and structural properties. Isocyanurate, ethane, mercaptopropyl, and ureidopropyl-functionalized mesoporous alumina materials were synthesized with relatively high surface area and large pore volume with uniform and wormhole-like mesopores. The presence of organosilyl groups within these hybrid materials was confirmed by IR or Raman spectroscopy and their concentration was determined by elemental analysis.

Grant SM; Woods SM; Gericke A; Jaroniec M

2011-11-01

239

Introduction of bridging and pendant organic groups into mesoporous alumina materials.  

Science.gov (United States)

Incorporation of organic functionalities into soft-templated mesoporous alumina was performed via organosilane-assisted evaporation induced self-assembly using aluminum alkoxide precursors and block copolymer templates. This strategy permits one to obtain mesoporous alumina-based materials with tailorable adsorption, surface and structural properties. Isocyanurate, ethane, mercaptopropyl, and ureidopropyl-functionalized mesoporous alumina materials were synthesized with relatively high surface area and large pore volume with uniform and wormhole-like mesopores. The presence of organosilyl groups within these hybrid materials was confirmed by IR or Raman spectroscopy and their concentration was determined by elemental analysis. PMID:21988174

Grant, Stacy M; Woods, Stephan M; Gericke, Arne; Jaroniec, Mietek

2011-10-25

240

LISA long-arm interferometry  

Energy Technology Data Exchange (ETDEWEB)

The Laser Interferometer Space Antenna (LISA) will observe gravitational radiation in the millihertz band by measuring picometer-level fluctuations in the distance between drag-free proof masses over baselines of approximately 5 x 10{sup 9}m. The measurement over each baseline will be divided into three parts: two 'short-arm' measurements between the proof masses and a fiducial point on their respective spacecraft, and a 'long-arm' measurement between fiducial points on separate spacecraft. This work focuses on the technical challenges associated with these long-arm measurements and the techniques that have been developed to overcome them.

Thorpe, James Ira, E-mail: james.i.thorpe@nasa.go [NASA/GSFC, Greenbelt, MD 20771 (United States)

2010-04-21

 
 
 
 
241

ARM Lead Mentor Selection Process  

Energy Technology Data Exchange (ETDEWEB)

The ARM Climate Research Facility currently operates more than 300 instrument systems that provide ground-based observations of the atmospheric column. To keep ARM at the forefront of climate observations, the ARM infrastructure depends heavily on instrument scientists and engineers, also known as Instrument Mentors. Instrument Mentors must have an excellent understanding of in situ and remote-sensing instrumentation theory and operation and have comprehensive knowledge of critical scale-dependent atmospheric processes. They also possess the technical and analytical skills to develop new data retrievals that provide innovative approaches for creating research-quality data sets.

Sisterson, DL

2013-03-13

242

Locking arm for well tool  

Energy Technology Data Exchange (ETDEWEB)

A well tool is described, comprising: a housing; a locking arm mounted in the housing for movement between a retracted position and a deployment position; a first piston for moving the arm from the retracted position to the deployed position; and a second piston having a cross-sectional area larger than the cross-sectional area of the first piston for locking the arm in the deployed position wherein the first piston is slidably positioned within a bore formed in the second piston.

Petermann, S.G.

1989-04-11

243

Rocker arm pivot assembly  

Energy Technology Data Exchange (ETDEWEB)

A rocker arm pivot assembly for valve gear of an engine is described comprising: (a) an elongated post member having means for attachment thereto provided on one end thereof and a reaction surface disposed distally of the attachment means and extending in a direction to resist loads applied thereto generally in the direction of elongation of the post; (b) a fulcrum member having the post member received therethrough, the fulcrum registered on one side thereof against the reaction surface and having a pair of journalling surfaces thereon extending transversely of the post in opposing directions; (c) rolling bearing means received on each of the journalling surfaces of the fulcrum member; (d) a semi-cylindrical sleeve member with the post member received therethrough, the sleeve member having a pair of spaced journalling surfaces provided on the inner periphery thereof, the surfaces each contacting one of the bearing means; (e) flexible retaining means with the post member received therethrough, the retaining means including journalling surfaces formed thereon engageable with the bearing means, and means formed thereon engaging the sleeve whereby the bearing means are maintained in position between the sleeve and the retaining means; and (f) spacer means operative to maintain the fulcrum member in contact with the post reaction surface upon attachment of the post member to an engine.

Clark, D.P.

1988-01-12

244

ARM Standards Policy Committee Report  

Energy Technology Data Exchange (ETDEWEB)

Data and metadata standards promote the consistent recording of information and are necessary to ensure the stability and high quality of Atmospheric Radiation Measurement (ARM) Climate Research Facility data products for scientific users. Standards also enable automated routines to be developed to examine data, which leads to more efficient operations and assessment of data quality. Although ARM Infrastructure agrees on the utility of data and metadata standards, there is significant confusion over the existing standards and the process for allowing the release of new data products with exceptions to the standards. The ARM Standards Policy Committee was initiated in March 2012 to develop a set of policies and best practices for ARM data and metadata standards.

Cialella, A; Jensen, M; Koontz, A; McFarlane, S; McCoy, R; Monroe, J; Palanisamy, G; Perez, R; Sivaraman, C

2012-09-19

245

ARM: A climate process observatory  

Energy Technology Data Exchange (ETDEWEB)

In May 1992 the Department of Energy`s Atmospheric Radiation Measurement (ARM) Program began deploying instrumentation and conducting measurements at its first field site near Lamont in North Central Oklahoma. ARM is a major program of atomospheric measurement and modeling intended to improve understanding of the processes and properties that affect atmospheric radiation. Particular emphasis is being placed on the role of clouds in radiative transport and on improving the representation of clouds and cloud radiative properties in climate models. In this paper we provide a brief overview of the ARM Program. We discuss the philosophy behind the ARM experiment design, describe the types of experiments underway and their objectives, and we portray how the suite of instrumentation and the observational strategy is expected to evolve as the process of experiment design, hypothesis testing, and learning plays out over the next decade.

Stokes, G.M.; Pennell, W.T.

1994-01-01

246

Arm fat and muscle areas in infancy.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Growth of arm muscle, fat and water areas were evaluated longitudinally in a prospective study in 81 infants from birth to the age of 12 months. The percentage of arm fat area v the cross sectional upper arm area increased at the age of 15 days with a peak peak at the age of 6 months while arm muscl...

Sann, L; Durand, M; Picard, J; Lasne, Y; Bethenod, M

247

Laboratory Syntheses of Insect Pheromones.  

Science.gov (United States)

Provides background information and procedures for the multi-step synthesis of tiger moth and boll weevil pheromones (sex attractants). These syntheses require several laboratory periods. The tiger moth pheromone synthesis is suitable for introductory organic chemistry while the boll weevil pheromone is recommended for an advanced laboratory…

Cormier, Russell A.; Hoban, James N.

1984-01-01

248

Method of synthesizing pyrite nanocrystals  

Energy Technology Data Exchange (ETDEWEB)

A method of synthesizing pyrite nanocrystals is disclosed which in one embodiment includes forming a solution of iron (III) diethyl dithiophosphate and tetra-alkyl-ammonium halide in water. The solution is heated under pressure. Pyrite nanocrystal particles are then recovered from the solution.

Wadia, Cyrus; Wu, Yue

2013-04-23

249

Phosphodiester cleavage properties of copper(II) complexes of 1,4,7-triazacyclononane ligands bearing single alkyl guanidine pendants.  

UK PubMed Central (United Kingdom)

Three new metal-coordinating ligands, L(1)·4HCl [1-(2-guanidinoethyl)-1,4,7-triazacyclononane tetrahydrochloride], L(2)·4HCl [1-(3-guanidinopropyl)-1,4,7-triazacyclononane tetrahydrochloride], and L(3)·4HCl [1-(4-guanidinobutyl)-1,4,7-triazacyclononane tetrahydrochloride], have been prepared via the selective N-functionalization of 1,4,7-triazacyclononane (tacn) with ethylguanidine, propylguanidine, and butylguanidine pendants, respectively. Reaction of L(1)·4HCl with Cu(ClO(4))(2)·6H(2)O in basic aqueous solution led to the crystallization of a monohydroxo-bridged binuclear copper(II) complex, [Cu(2)L(1)(2)(?-OH)](ClO(4))(3)·H(2)O (C1), while for L(2) and L(3), mononuclear complexes of composition [Cu(L(2)H)Cl(2)]Cl·(MeOH)(0.5)·(H(2)O)(0.5) (C2) and [Cu(L(3)H)Cl(2)]Cl·(DMF)(0.5)·(H(2)O)(0.5) (C3) were crystallized from methanol and DMF solutions, respectively. X-ray crystallography revealed that in addition to a tacn ring from L(1) ligand, each copper(II) center in C1 is coordinated to a neutral guanidine pendant. In contrast, the guanidinium pendants in C2 and C3 are protonated and extend away from the Cu(II)-tacn units. Complex C1 features a single ?-hydroxo bridge between the two copper(II) centers, which mediates strong antiferromagnetic coupling between the metal centers. Complexes C2 and C3 cleave two model phosphodiesters, bis(p-nitrophenyl)phosphate (BNPP) and 2-hydroxypropyl-p-nitrophenylphosphate (HPNPP), more rapidly than C1, which displays similar reactivity to [Cu(tacn)(OH(2))(2)](2+). All three complexes cleave supercoiled plasmid DNA (pBR 322) at significantly faster rates than the corresponding bis(alkylguanidine) complexes and [Cu(tacn)(OH(2))(2)](2+). The high DNA cleavage rate for C1 {k(obs) = 1.30 (±0.01) × 10(-4) s(-1) vs 1.23 (±0.37) × 10(-5) s(-1) for [Cu(tacn)(OH(2))(2)](2+) and 1.58 (±0.05) × 10(-5) s(-1) for the corresponding bis(ethylguanidine) analogue} indicates that the coordinated guanidine group in C1 may be displaced to allow for substrate binding/activation. Comparison of the phosphate ester cleavage properties of complexes C1-C3 with those of related complexes suggests some degree of cooperativity between the Cu(II) centers and the guanidinium groups.

Tjioe L; Joshi T; Forsyth CM; Moubaraki B; Murray KS; Brugger J; Graham B; Spiccia L

2012-01-01

250

Regenerator cross arm seal assembly  

Energy Technology Data Exchange (ETDEWEB)

In a gas turbine engine having block means defining a pressurized air passage and a hot exhaust gas passage and a cross arm partition separating portions of the air and the exhaust passages, a regenerator disc on the block means intersecting the air and the exhaust passages and rotatable to transfer heat from the exhaust gas to the pressurized air and including an inboard surface, and rim seal means between the disc inboard surface and the block means operative to prevent pressurized air and exhaust gas leakage around the periphery of the disc, an improved cross arm seal assembly is described comprising: a platform generally extensive with the cross arm partition disposed between the latter and the disc inboard surface, a porous and compliant support layer on a surface of the platform facing the disc inboard surface, a seal and wear layer on the support layer defining a barrier to gas passage and sealingly engaging the disc inboard surface, dike means between the seal and wear layer and the platform preventing communication through the support layer between the air and the exhaust passages, seal means between the platform and the cross arm partition preventing communication between the air and the exhaust passages across the cross arm partition, and means on the block means and on the platform operative to direct air from the pressurized air passage to and through the support layer thereby to cool the seal and wear layer.

Jackman, A.V.

1988-01-12

251

Azathia crown ethers carrying pyrene pendant as receptor molecules for metal sensor systems  

International Nuclear Information System (INIS)

A series of crown ethers carrying a pyrene group with nitrogen-sulfur donor atoms, that differ in having three, four and five sulfur atoms in the macrocycle was designed and synthesized by the reaction of the corresponding macrocyclic compound and 1-bromomethylpyrene. The influence of metal cations such as Mn2+, Fe2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Hg2+, Pb2+ and Al3+ on the spectroscopic properties of the ligands was investigated in acetonitrile-dichloromethane (1:1) by means of absorption and emission spectrometry. Absorption spectra show isosbestic points in the spectrophotometric titration of Fe2+, Zn2+, Cu2+, Pb2+ and Hg2+. The results of spectrophotometric titration experiments disclosed the complexation compositions and complex stability constants of the novel ligands with Fe2+, Zn2+, Cu2+, Pb2+ and Hg2+ cations. The monoazatetrathia crown ether showed good sensitivity for Cu2+ with linearity in the range 5.0x10-7-2.5x10-6 M and detection limit of 1.6x10-8 M. - Research highlights: ? We report a series of crown ethers carrying a pyrene group with nitrogen-sulfur donor atoms. ? The influence of metal cations on the spectroscopic properties of the ligands is investigated. ? We have carried out the monoazatetrathia crown ether showed good sensitivity for Cu2+.

2011-01-01

252

The polymer electrolyte based on polysiloxane containing both alkyl cyanide and oligo ethylene oxide pendants  

International Nuclear Information System (INIS)

[en] The monomers (3-cyanopropyl) methylsiloxane cyclics (D4CN) and (3-(2-(2-(2-methoxyethoxy)ethoxy)ethoxy)propyl) methylsiloxane cyclics (D4TEG) were prepared by a hydrosilylation reaction of 2,4,6,8-tetramethylcyclotetrasiloxane (D4H) with allyl cyanide and tri(ethylene glycol) methyl allyl ether (allyl TEG), respectively, in toluene using a platinum(0)-1,3-divinyl-1,1,3,3-tetramethyl disiloxane complex as the catalyst. The new crosslinkable polymers with alkyl cyanide and ethylene oxide groups as the pendent were synthesized by ring opening polymerization and characterized by GPC and 1H NMR. And then, the crosslinked solid polymer electrolyte was prepared by UV radiation curing. The conductivities of samples were measured by impedance spectroscopy using an indium-tin oxide (ITO) electrode. As the results, the maximum ionic conductivities of the polymer were 1.15 x 10-5 S cm-1 at 20 deg. C and 1 x 10-4 S cm-1 at 60 deg. C. The electrolyte was stable electrochemically to 5 V versus Li+/Li at room temperature

2004-11-30

253

Les infirmières-visiteuses pendant l’entre-deux-guerres en Haute-Normandie : entre professionnalisme officiel et bénévolat officieux  

Directory of Open Access Journals (Sweden)

Full Text Available Marginale avant 1914, révélée pendant la Première Guerre mondiale, adulée ou décriée pendant l’entre-deux-guerres, l’évolution de la profession d’infirmière-visiteuse est étrangement commune à l’évolution de la place des femmes dans le travail salarié. En effet, même si une législation est venue encadrer ce nouveau corps de femmes au début des années vingt, force est de constater, au travers des exemples des départements de Seine-Inférieure et de l’Eure, que celui-ci a gardé de nombreux attributs propres au bénévolat. D’ailleurs, bien que les dirigeants de l’action antituberculeuse, Albert Calmette en tête, aient régulièrement encensé la profession, ils ont néanmoins cherché à l’encadrer strictement, redoutant des envies trop fortes d’autonomie. À cette professionnalisation toute relative se sont ajoutées des conditions de travail particulièrement rudes pour ces jeunes femmes novices, finalement peu préparées à côtoyer une misère insoupçonnée. Ainsi, si la fonction d’infirmière-visiteuse correspond à un virage non négligeable dans l’acceptation du travail qualifié des femmes par la société, son efficacité dans le cadre des luttes contre les fléaux sociaux (tuberculose et mortalité infantile) reste tout de même mesurée dans les faits.The evolutions of the status of the visiting nurse echo the evolution in women's position within the workforce: marginal prior to 1914, revealed during the First World War, idolized or disparaged in the inter-war years. Despite legislation governing this new corps of women nurses in the early twenties, examples from the departments of the Seine-Inférieure and  the Eure make clear that it retained many attributes of volunteer work. Moreover, although the leaders of the war against tuberculosis, such as Albert Calmette, regularly praised the profession, they nonetheless sought to regulate it strictly, fearing a move toward excessive autonomy. The article considers the nature of this relative professionalization as well as the particularly difficult working conditions of these novice women professionals, who were ultimately ill-equipped to handle the misery they encountered.  Thus, while the emergence of the visiting nurse represented a major shift in the acceptance of women’s skilled work in French society, the ability of these women to exert their skills effectively in the context of struggles against social scourges (tuberculosis and infant mortality) was limited in practice.

Stéphane Henry

2009-01-01

254

Les inhibiteurs sp?cifiques du recaptage de la s?rotonine pendant la grossesse et l?issue du nourrisson.  

UK PubMed Central (United Kingdom)

R?SUM?Il est tr?s important de bien soigner la d?pression pendant la grossesse pour la sant? de la m?re, du f?tus, puis du nouveau-n?. Les inhibiteurs s?lectifs du recaptage de la s?rotonine (ISRS) sont souvent utilis?s comme antid?presseurs. D?apr?s une ?tude am?ricaine, environ 7 % des femmes enceintes se sont fait prescrire des ISRS en 2004?2005. L?utilisation d?ISRS pendant le premier trimestre, dans leur ensemble, risque peu d?accro?tre le risque de malformations cong?nitales. La parox?tine peut s?associer ? une l?g?re augmentation du risque de malformations cardiaques, mais les donn?es probantes demeurent non concluantes. L?exposition du f?tus aux ISRS plus pr?s du moment de l?accouchement peut entra?ner des sympt?mes respiratoires, moteurs, gastro-intestinaux et du syst?me nerveux central chez environ 10 % ? 30 % des nouveau-n?s (syndrome du comportement n?onatal li? ? l?exposition aux ISRS). Ces sympt?mes sont g?n?ralement b?nins et transitoires. L?hypertension pulmonaire persistante du nouveau-n? est une cons?quence extr?mement rare d?exposition du f?tus aux ISRS. Il faudrait tenir compte de ces renseignements pour prendre des d?cisions risques-avantages individuelles lorsqu?on envisage le traitement de la d?pression pendant la grossesse. Les nouveau-n?s expos?s aux ISRS en fin de grossesse devraient demeurer en observation ? l?h?pital pendant au moins 48 heures.

Jefferies AL

2011-11-01

255

ARM Education Center: Lesson Plans  

Science.gov (United States)

The Atmospheric Radiation Measurement (ARM) Program is described as an important part of the US Department of Energy's strategy to understand global climate change. The ARM Education and Outreach Program offers the Lesson Plans Web site that strives to create basic science lessons related to weather and climate for K-12. Educators will find lessons on outgassing, air density and temperature, air pressure, winds, making clouds, the effect of solar radiation on land and sea, coastal erosion, acid rain, and many more -- each with a complete description of methods and materials needed. Other resources that can be found on the site include an extensive atmospheric science glossary, a learn how to graph activity, specific lessons that utilize ARM's Program data, quizzes, and related links.

256

Utility insulated cross-arm  

Energy Technology Data Exchange (ETDEWEB)

A utility insulated cross-arm is described for supporting electrical wires from a utility pole comprising: a triangular frame having a base and a peak, the triangular frame being constructed from an insulative material; left and right horizontal cross-arms integral with the triangular frame and constructed from an insulative material, located at the base of the triangular frame, the horizontal cross-arms each having an upper surface; an upper support member integral with and located at the peak of the triangular frame and construct ed from an insulative material; attachment means for attaching the electrical wire to the upper support member; and mounting means for mounting the triangular frame to the utility pole, the mounting means comprised of holes located along a vertical centerline of the triangular frame, for bolting the triangular frame to the utility pole.

King, H.C. Jr.; King, N.

1987-07-28

257

Arms Control past and future  

Energy Technology Data Exchange (ETDEWEB)

I am going to talk today about Arms Control. First, I want to go over the recent history of the process. Five years ago, the pace of arms control changed dramatically. From an outsider it probably didn't appear that way -- but those working it, the shift from the historic glacial speed normally associated with this process to one of pressures -- political and economic -- national and global -- to actually conclude meaningful, verifiable agreements was a major change. Then, I want to spend a few minutes covering the future of arms control new that we have lost our enemy, and it is no longer a bipolar world. I also want to leave time for easy questions.

Fox, T.R.

1991-12-01

258

Arms Control past and future  

Energy Technology Data Exchange (ETDEWEB)

I am going to talk today about Arms Control. First, I want to go over the recent history of the process. Five years ago, the pace of arms control changed dramatically. From an outsider it probably didn`t appear that way -- but those working it, the shift from the historic glacial speed normally associated with this process to one of pressures -- political and economic -- national and global -- to actually conclude meaningful, verifiable agreements was a major change. Then, I want to spend a few minutes covering the future of arms control new that we have lost our enemy, and it is no longer a bipolar world. I also want to leave time for easy questions.

Fox, T.R.

1991-12-01

259

METHOD FOR SYNTHESIZING TETRAHYDROBIOPTERIN MASSIVELY  

UK PubMed Central (United Kingdom)

PURPOSE: A method for synthesizing tetrahydrobiopterin massively is provided, thereby easily and cheaply preparing tetrahydrobiopterin useful for medical applications. CONSTITUTION: A vector contains a polynucleotide encoding dihydroneopterin triphosphate 2'-epimerase of SEQ ID NO: 1 and the antibiotic resistant gene sequence, wherein the antibiotic resistant gene is selected from kanamycin resistant gene, chloramphenicol resistant gene and tetracycline resistant gene; and the vector is pMPSA. A recombinant cell is prepared by using the polynucleotide encoding dihydroneopterin triphosphate 2'-epimerase of SEQ ID NO: 1 and the antibiotic resistant gene sequence, wherein the cell is Escherichia coli MPSA-KO(DE3) KCTC 10313BP.A method for synthesizing tetrahydrobiopterin massively comprises blocking the biosynthesis pathway from dihydroneopterin triphosphate to monapterin to facilitate the biosynthesis of a teridine compound, wherein the teridine compound is tetrahydrobiopterin; and the monapterin biosynthesis pathway is blocked by knock out of dihydroneopterin triphosphate 2'-epimerase.

AHN CHI YOUNG; YIM JEONG BIN

260

Synthesis and electrochemical studies of cobalt(III) monohydride complexes containing pendant amines.  

Science.gov (United States)

Two new tetraphosphine ligands, P(nC-PPh2)2N(Ph)2 (1,5-diphenyl-3,7-bis((diphenylphosphino)alkyl)-1,5-diaza-3,7-diphosphacyclooctane; alkyl = (CH2)2, n = 2 (L2); (CH2)3, n = 3 (L3)), have been synthesized. Coordination of these ligands to cobalt affords the complexes [Co(II)(L2)(CH3CN)](2+) and [Co(II)(L3)(CH3CN)](2+), which are reduced by KC8 to afford [Co(I)(L2)(CH3CN)](+) and [Co(I)(L3)(CH3CN)](+). Protonation of the Co(I) complexes affords [HCo(III)(L2)(CH3CN)](2+) and [HCo(III)(L3)(CH3CN)](2+). The cyclic voltammetry of [HCo(III)(L2)(CH3CN)](2+), analyzed using digital simulation, is consistent with an ErCrEr reduction mechanism involving reversible acetonitrile dissociation from [HCo(II)(L2)(CH3CN)](+) and resulting in formation of HCo(I)(L2). Reduction of HCo(III) also results in cleavage of the H-Co bond from HCo(II) or HCo(I), leading to formation of the Co(I) complex [Co(I)(L2)(CH3CN)](+). Under voltammetric conditions, the reduced cobalt hydride reacts with a protic solvent impurity to generate H2 in a monometallic process involving two electrons per cobalt. In contrast, under bulk electrolysis conditions, H2 formation requires only one reducing equivalent per [HCo(III)(L2)(CH3CN)](2+), indicating a bimetallic route wherein two cobalt hydride complexes react to form 2 equiv of [Co(I)(L2)(CH3CN)](+) and 1 equiv of H2. These results indicate that both HCo(II) and HCo(I) can be formed under electrocatalytic conditions and should be considered as potential catalytic intermediates. PMID:23945020

Wiedner, Eric S; Roberts, John A S; Dougherty, William G; Kassel, W Scott; DuBois, Daniel L; Bullock, R Morris

2013-08-14

 
 
 
 
261

Synthesis and Electrochemical Studies of Cobalt(III) Monohydride Complexes Containing Pendant Amines.  

UK PubMed Central (United Kingdom)

Two new tetraphosphine ligands, P(nC-PPh2)2N(Ph)2 (1,5-diphenyl-3,7-bis((diphenylphosphino)alkyl)-1,5-diaza-3,7-diphosphacyclooctane; alkyl = (CH2)2, n = 2 (L2); (CH2)3, n = 3 (L3)), have been synthesized. Coordination of these ligands to cobalt affords the complexes [Co(II)(L2)(CH3CN)](2+) and [Co(II)(L3)(CH3CN)](2+), which are reduced by KC8 to afford [Co(I)(L2)(CH3CN)](+) and [Co(I)(L3)(CH3CN)](+). Protonation of the Co(I) complexes affords [HCo(III)(L2)(CH3CN)](2+) and [HCo(III)(L3)(CH3CN)](2+). The cyclic voltammetry of [HCo(III)(L2)(CH3CN)](2+), analyzed using digital simulation, is consistent with an ErCrEr reduction mechanism involving reversible acetonitrile dissociation from [HCo(II)(L2)(CH3CN)](+) and resulting in formation of HCo(I)(L2). Reduction of HCo(III) also results in cleavage of the H-Co bond from HCo(II) or HCo(I), leading to formation of the Co(I) complex [Co(I)(L2)(CH3CN)](+). Under voltammetric conditions, the reduced cobalt hydride reacts with a protic solvent impurity to generate H2 in a monometallic process involving two electrons per cobalt. In contrast, under bulk electrolysis conditions, H2 formation requires only one reducing equivalent per [HCo(III)(L2)(CH3CN)](2+), indicating a bimetallic route wherein two cobalt hydride complexes react to form 2 equiv of [Co(I)(L2)(CH3CN)](+) and 1 equiv of H2. These results indicate that both HCo(II) and HCo(I) can be formed under electrocatalytic conditions and should be considered as potential catalytic intermediates.

Wiedner ES; Roberts JA; Dougherty WG; Kassel WS; Dubois DL; Bullock RM

2013-09-01

262

Catalytic method for synthesizing hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

A method for synthesizing hydrocarbons from carbon monoxide and hydrogen by contacting said gases with a slurry of a catalyst composed of palladium or platinum and cobalt supported on a solid phase is disclosed. The catalyst is prepared by heating a heterogeneous component of the palladium or platinum deposited on the solid support in a solution of cobalt carbonyl or precursors thereof. The catalyst exhibits excellent activity, stability in air, and produces highly desirable product fractions even with dilute gaseous reactants.

Sapienza, Richard S. (Shoreham, NY); Sansone, Michael J. (Summit, NJ); Slegeir, William A. R. (Hampton Bays, NY)

1984-01-01

263

ARM Static Library Identification Framework  

Directory of Open Access Journals (Sweden)

Full Text Available A static library identification framework is proposed through studying library as “dcc”, which dynamically extracts binary characteristic file on applications under ARM processor. This framework obtains function modules according to ARM assemble characteristics, on the basis of which dynamic signature is generated due to pattern files through analyzing coding characteristics of assemble addressing mode and that of corresponding binary codes, then signatures of candidate functions are matched with signatures of library functions using hash algorithm to identify library functions. This method can recognize library functions efficiently and solve conflict between massive library files and matching efficiency effectively.

Qing Yin; Fei Huang; Liehui Jiang

2010-01-01

264

[MR imaging of the arm].  

Science.gov (United States)

Thirty arms of healthy adults were studied with MR imaging using surface coil. Fine structures of the arm, such as muscular bundles, small vessels and nerves were clearly demonstrated. Deep fascia dividing muscular bundles appeared as high intensity on T1-weighed image due to fat deposition beneath the fascia. Aponeurosis is also flat sheet of densely arranged collagen fibers. With rather thicker layer of collagen fibers than fascia, aponeurosis appeared as low intensity sheet that was frequently demonstrated on MR images of the extremities. PMID:2232278

Niitsu, M; Anno, I; Matsumoto, K; Kuno, S; Akisada, M

1990-09-01

265

[MR imaging of the arm  

UK PubMed Central (United Kingdom)

Thirty arms of healthy adults were studied with MR imaging using surface coil. Fine structures of the arm, such as muscular bundles, small vessels and nerves were clearly demonstrated. Deep fascia dividing muscular bundles appeared as high intensity on T1-weighed image due to fat deposition beneath the fascia. Aponeurosis is also flat sheet of densely arranged collagen fibers. With rather thicker layer of collagen fibers than fascia, aponeurosis appeared as low intensity sheet that was frequently demonstrated on MR images of the extremities.

Niitsu M; Anno I; Matsumoto K; Kuno S; Akisada M

1990-09-01

266

A complex of cyclohexane-1,2-diaminoplatinum with an amphiphilic biodegradable polymer with pendant carboxyl groups.  

UK PubMed Central (United Kingdom)

A biodegradable and amphiphilic copolymer, MPEG-b-P(LA-co-MCC), which contains pendant carboxyl groups, was chosen as a drug carrier for the active anticancer part (DACH-Pt) of oxaliplatin to form an MPEG-b-P(LA-co-MCC/Pt) complex. It was able to self-assemble into micelles with a mean diameter of 30-40 nm, and a surface potential near -10 mV. The typical platinum content was 10 wt.%. The micelles showed acid-responsive drug release kinetics, which is beneficial for drug release in the intracellular environment. The Pt(II) species were released mainly in the form of DACH-Pt-Cl(2) in 150 mM NaCl solution and DACH-Pt(2+)-(H(2)O)(2) in pure water according to the results obtained by high-performance liquid chromatography coupled with inductively coupled plasma mass spectrometry and X-ray photoelectron spectroscopy. In vitro evaluation showed that the micelles displayed the same or higher cytotoxicities against SKOV-3, HeLa, and EC-109 cancer cells compared with oxaliplatin. The enhanced cytotoxicity against SKOV-3 cells is attributed to effective internalization of the micelles by the cells via endocytosis and the sensitivity of SKOV-3 cells to platinum drugs. This novel biodegradable and amphiphilic copolymer-based platinum drug will have great potential application in clinical use.

Xiao H; Zhou D; Liu S; Zheng Y; Huang Y; Jing X

2012-05-01

267

Sensibilité des œufs de truite arc-en-ciel aux chocs mécaniques pendant la phase de durcissement  

Directory of Open Access Journals (Sweden)

Full Text Available Des œufs de Truite arc-en-ciel en provenance de plusieurs femelles ont été transférés en eau douce après insémination et soumis à une agitation mécanique pendant une heure. Généralement on observe après 30 mn d'agitation une diminution du pourcentage d'œufs embryonnés qui est significative (P Eggs provided by several rainbow trout (Salmo gairdneri) were placed in freshwater after insemination and agitated mechanically for one hour. Usually agitation for more than 30 minutes significantly reduced the percentage of eggs found developing at 100 degree-days (P < 0.001 and P < 0.05). In one case no significant reduction was found. If agitation occurs between 30 and 60 minutes after egg transfer to freshwater no reduction of developing eggs was found. Therefore there is no particularly sensitive stage. during hardening ; total duration of agitation is the most important factor. These results show that embryonic development of eggs for some females may be reduced by prolonged agitation of eggs during the phase of hardening. The manipulation of fertilized eggs should be avoided after the first hour in freshwater.

BILLARD R.

2008-01-01

268

Fabrication and bioproperties of raspberry-type hybrid nanoparticles of Au-thioethyl pendant ligand@chitosan.  

UK PubMed Central (United Kingdom)

Synthesis of nanoparticles with desired size/morphology has enormous importance, especially in the compelling field of nanotechnology. In this case, a novel kind of raspberry-type hybrid nanoparticles was prepared by hybridization of chitosan (CS) with thioethyl pendant ligand (TPL) modified Au nanoparticles (Au-TPL@CS NPs). Such method was based on ionic gelation using sodium tripolyphosphate as a counterion. The blood compatibility of Au-TPL@CS NPs was characterized by coagulation tests, plasma recalcification time, hemolysis assay, morphological changes of red blood cells (RBCs) and complement activation in vitro. The results showed that Au-TPL@CS NPs exhibited good blood compatibility. The possible underlying mechanism was also present. Finally, the direct electron transfer reactivity of the Hemoglobin/Au-TPL@CS NPs/multi-walled carbon nanotubes/glassy carbon electrode was investigated with cyclic voltammetry measurements. The biosensor exhibited a good electrocatalytic activity to the reduction of H2O2. Such new type of Au-TPL@CS NPs provides a promising platform of biological system for early illness detection and treatment in future.

Huang B; Tong F; Chen Y; Zhu Q; Xing L; Lv M; Mao C; Lu Z; Shen J

2013-01-01

269

Synthesis and characterization of novel polyamide-ethers based on bis-imidazole containing bulky aryl pendant groups  

Scientific Electronic Library Online (English)

Full Text Available Abstract in english A series of novel polyamide-ethers (PAEs) based on bis-imidazole containing bulky aryl pendant groups was prepared by direct polycondensation of a diamine, 4-(1-(4-(4-(2-(4-aminophenyl)-4,5-diphenyl-1H-imidazol-1-yl)phenoxy)phenyl)-4,5-diphenyl-1H-imidazol-2-yl)benzenamine (DABI), and various dicarboxylic acids. All the resulting polyamide-ethers were amorphous with inherent viscosities ranged from 0.52 to 0.61 dL/g and were readily soluble in many organic solvents which (more) could be solution-cast into transparent and tough films. The glass transition temperatures (Tg) of these polymers were affected considerably by their chemical structure and ranged from 230 to 310 ºC. They had useful levels of thermal stability associated with relatively high temperatures of 10% weight loss (T10) in the range of 329-399 ºC in air atmosphere.

Saadati, Seyed Mahdi; Mosslemin, Mohammad Hossein; Behmadi, Hossein

2013-01-01

270

ARM Data for Cloud Parameterization  

Energy Technology Data Exchange (ETDEWEB)

The PI's ARM investigation (DE-IA02-02ER633 18) developed a physically-based subgrid-scale saturation representation that fully considers the direct interactions of the parameterized subgrid-scale motions with subgrid-scale cloud microphysical and radiative processes. Major accomplishments under the support of that interagency agreement are summarized in this paper.

Xu, Kuan-Man

2006-10-02

271

Tamasese distributing arms, Apia, Samoa  

Digital Repository Infrastructure Vision for European Research (DRIVER)

200 x 145 mm. A view showing Tamasese sitting on the ground, with rifles in front of him, and people sitting around. British sailors stand on the verandah of the building in the background. Tamasese was vice-king to Malietoa Tahu, whom Britain supported for the kingship. The arms seen here were ...

272

The Arm Prime Factors Decomposition  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We introduce the Arm prime factors decomposition which is the equivalent of the Taylor formula for decomposition of integers on the basis of prime numbers. We make the link between this decomposition and the p-adic norm known in the p-adic numbers theory. To see how it works, we give examples of the...

Arm, Boris

273

The p-Arm Theory  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We introduce the p-Arm theory which give rise to a new mathematical object that we call the "p-exponential" which is invariant under p derivation. We calculate its derivate and we use this new function to solve di erential equations. Next, we de ne its real and imaginary part which are the p-cosinus...

Arm, Boris

274

Super gripper variable vane arm  

Energy Technology Data Exchange (ETDEWEB)

This patent describes in combination with a turbine engine, a variable vane assembly comprising: a vane system which may be rotated. The vane stem has a tip with first and second parallel slots on opposite sides of it spaced below the vane stem's tip. The vane stem has an end slot in the tip, the end slot, being perpendicular to the first and second parallel slots; and a vane arm which integrally fits on the tip of the vane stem without threaded fasteners, the vane arm thereby being capable of being rotated by the vane stem within the turbine engine. The vane arm comprises a flat wide metal strip with two ears near one end, the ears being outer edges of the metal strip which are turned outwards to engage the first and second parallel slots in the vane stem. The metal strip also has a central leaf which turns downwards between the two ears to engage the end slot in the tip of the vane stem. The central leaf thereby serves as an axial retainer as the vane stem rotates the vane arm.

Ludwick, G.E.

1987-05-26

275

MOBILE ARM RETRIEVAL SYSTEM (MARS)  

International Nuclear Information System (INIS)

[en] The power point presentation included an overview of the Mobile Arm Retreival System (MARS) including background information, schedule and design strategy, and described the sound tank system, assumed leaking tank system, key technical issues, the design progress, and the fabrication process

2009-01-01

276

Scanning ARM Cloud Radar Handbook.  

Science.gov (United States)

The scanning ARM cloud radar (SACR) is a polarimetric Doppler radar consisting of three different radar designs based on operating frequency. These are designated as follows: (1) X-band SACR (X-SACR); (2) Ka-band SACR (Ka-SACR); and (3) W-band SACR (W-SAC...

K. Johnson K. Widener N. Bharadwaj

2012-01-01

277

Nuclear physicist, arms control advocate  

CERN Multimedia

Victor F. Weisskopf, a nuclear physicist who worked on the Manhattan Project to build the first atomic bomb in World War II and later became an ardent advocate of arms control, died Monday at his home in Newton, MA, USA. He was 93 (1 page).

Chang, K

2002-01-01

278

Worldwide report: Arms control, [October 4, 1985  

Energy Technology Data Exchange (ETDEWEB)

This document contains articles on arms control throughout the world. Some topics discussed are strategic defense initiative, space arms, intermediate range nuclear forces, disarmament, chemical and biological weapons, and nuclear testing.

NONE

1985-10-04

279

JPRS report: Arms control, [June 30, 1987  

Energy Technology Data Exchange (ETDEWEB)

This document contains articles translated from foreign periodicals into English concerning arms control throughout the world. Some topics discussed are strategic defense initiative, space arms, intermediate range nuclear forces, chemical and biological weapons, and nuclear testing.

NONE

1987-06-30

280

Worldwide report: Arms control, [January 13, 1986  

Energy Technology Data Exchange (ETDEWEB)

This document contains articles on arms control throughout the world. Some topics discussed are SDI and space arms, US-USSR Geneva talks, chemical-biological weapons, conferences, negotiations, reductions, national security and disarmament.

NONE

1986-01-13

 
 
 
 
281

Herpes zoster (shingles) on the arm (image)  

Science.gov (United States)

... a picture of herpes zoster (shingles) on the arm. Shingles are caused by the same virus that ... skin. This distribution pattern, seen here on the arm, follows a dermatome (see the "dermatomes" picture).

282

JPRS report: Arms control, [January 4, 1991  

Energy Technology Data Exchange (ETDEWEB)

This document contains articles from foreign periodicals that have been translated into English. These articles concern arms control. Topics include strategic defense initiative, conventional forces in Europe, space arms, nuclear forces, nuclear testing, security, disarmament and military doctrine.

NONE

1991-01-04

283

New technologies and the arms race  

Energy Technology Data Exchange (ETDEWEB)

This volume contains the proceedings of the International Conference on Technology, the Arms Race and Arms Control. Topics covered include: Cosmic space and the role of Europe and Non-military justification for investments in military technologies.

Schaerf, C.; Reid, B.H.; Carlton, D.

1989-01-01

284

Low-cost robotic arm control  

Science.gov (United States)

A low-cost robotic arm and controller system is presented. The controller is a desktop model of the robotic arm with the same degrees of freedom whose joints are equipped with sensors. Manipulating the controller by hand causes the robotic arm to mimic the movement in maser-slave fashion. The system takes advantage of the low cost and wide availability of hobby radio control components and uses a low-cost, easy-to-program microprocessor. The system is implemented with a video camera on the robotic arm, and the arm is mounted on an unmanned omnidirectional vehicle inspection robot. With a camera on the end of a robot arm, the vehicle inspection system can reach difficult to-access regions of the vehicle underbody. Learning to manipulate the robot arm with this controller is faster than learning with a traditional joystick. Limitations of the microcontroller are discussed, and suggestions for further development of the robot arm and control are made.

Rogers, John R.

2008-05-01

285

Fiber-optic color synthesizer.  

UK PubMed Central (United Kingdom)

Full-color synthesis was achieved, for what we believe is the first time, utilizing a novel 3x1 hard polymer-clad fiber coupler along with red, green, and blue (RGB) LED primaries. By using RGB LEDs that are coupled to three input ports, the device rendered full color from the output port with a circular emitting pixel of 135 microm in diameter with an extended color gamut. The proposed fiber-optic color synthesizer can provide a compact waveguide solution for the beam scanning display and the tunable pure white source for LED backlighting.

Jeong Y; Lee D; Lee JW; Oh K

2006-07-01

286

Method of synthesizing tungsten nanoparticles  

Energy Technology Data Exchange (ETDEWEB)

A method to synthesize tungsten nanoparticles has been developed that enables synthesis of nanometer-scale, monodisperse particles that can be stabilized only by tetrahydrofuran. The method can be used at room temperature, is scalable, and the product concentrated by standard means. Since no additives or stabilizing surfactants are required, this method is particularly well suited for producing tungsten nanoparticles for dispersion in polymers. If complete dispersion is achieved due to the size of the nanoparticles, then the optical properties of the polymer can be largely maintained.

Thoma, Steven G; Anderson, Travis M

2013-02-12

287

Multiple Identifications in Multi-Armed Bandits  

CERN Document Server

We study the problem of identifying the top $m$ arms in a multi-armed bandit game. Our proposed solution relies on a new algorithm based on successive rejects of the seemingly bad arms, and successive accepts of the good ones. This algorithmic contribution allows to tackle other multiple identifications settings that were previously out of reach. In particular we show that this idea of successive accepts and rejects applies to the multi-bandit best arm identification problem.

Bubeck, Sébastien; Viswanathan, Nitin

2012-01-01

288

Dynamic arm swinging in human walking  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Humans tend to swing their arms when they walk, a curious behaviour since the arms play no obvious role in bipedal gait. It might be costly to use muscles to swing the arms, and it is unclear whether potential benefits elsewhere in the body would justify such costs. To examine these costs and benefi...

Collins, Steven H.; Adamczyk, Peter G.; Kuo, Arthur D.

289

JPRS report: Arms control, [June 25, 1987  

Energy Technology Data Exchange (ETDEWEB)

This document contains articles from foreign periodicals that have been translated into English. These articles concern arms control throughout the world. Some topics discussed are strategic defense initiative, space arms, US-USSR nuclear and space arms talks, intermediate-range nuclear forces, and nuclear testing.

NONE

1987-06-25

290

JPRS report: Arms control, [August 18, 1987  

Energy Technology Data Exchange (ETDEWEB)

This document contains articles translated from foreign periodicals into English that concern arms control throughout the world. Some topics that are discussed include strategic defense initiative, space arms, nuclear weapons, space arms talks, intermediate range nuclear forces, conferences, nuclear testing, and free zone proposals.

NONE

1987-08-18

291

Preventing Interstate Armed Conflict : whose responsibility?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This is a study of interstate armed conflict prevention. The concept of conflict, armed conflict and conflict prevention is defined and explained in order to be able to investigate if there is any single institution saddled with the responsibility of preventing interstate armed conflict and also to ...

Otunba, Ganiyu

292

Worldwide report: Arms control, [June 21, 1985  

Energy Technology Data Exchange (ETDEWEB)

This document contains articles on arms control throughout the world. Some topics discussed are national security, arms talks, international relations, space arms, strategic defense initiative, SALT/START issues, intermediate range nuclear forces, nuclear missiles, rockets, disarmament, nuclear free zones, chemical and biological weapons, policies, defense treaties and pacts, and nuclear testing.

NONE

1985-06-21

293

[Humeral fracture caused by arm wrestling  

UK PubMed Central (United Kingdom)

Humeral shaft fractures may occur as a result of arm wrestling ("Indian wrestling," "iron arm"), a contest in which the antagonists sit face-to-face, grip hands with their elbows on a table, and try to force the opponent's arm back. A case of this type is reported.

Alkalay I; Greenberg B; Daniel M

1981-02-01

294

PARLAK: Parametrized Lock Cache Synthesizer  

UK PubMed Central (United Kingdom)

thispaper, we present PARLAK, a parametrized lock cache synthesizer tool. PARLAK generates a synthesizable SoCLC architecture with a user specifiednumber of lock variables and user specified number and type(s) of processor(s).Several configurations of SoCLC hardware have been generated using PARLAK and the designs have been synthesized in Design Compiler fromSynopsys. For example, PARLAK can generate a full range of customized SoCLCs, from a version for two processors with 32 lock variables occupying1,790 gates of area to a version for 14 processors with 256 lock variables occupying 37,380 gates of area (in TSMC 0.25 technology). The synthesisarea results reported in this paper indicate that the area occupied by SoCLC increases linearly as the number of locks/processors is increased. PARLAKis an important contribution to IP-generator tools for both custom SoC design and programming of reconfigurable SoC designs.Categories and Subject Descriptors: B.5 [Hardware]: Register-Transfer-Level Implementation; B.5.2 [Register-Transfer-Level Implementation]:Design Aids; D.4 [Operating Systems]: Process Management; D.4.1 [Process Management]: Synchronization, Mutual ExclusionGeneral Terms: Design, PerformanceAdditional Key Words and Phrases: critical section, lock synchronization, multiprocessors, mutual exclusion, shared memory, synchronization1.

Bilge E. S. Akgul; Vincent J. Mooney

295

Performance of arm locking in LISA  

International Nuclear Information System (INIS)

For the Laser Interferometer Space Antenna (LISA) to reach its design sensitivity, the coupling of the free-running laser frequency noise to the signal readout must be reduced by more than 14 orders of magnitude. One technique employed to reduce the laser frequency noise will be arm locking, where the laser frequency is locked to the LISA arm length. In this paper we detail an implementation of arm locking. We investigate orbital effects (changing arm lengths and Doppler frequencies), the impact of errors in the Doppler knowledge that can cause pulling of the laser frequency, and the noise limit of arm locking. Laser frequency pulling is examined in two regimes: at lock acquisition and in steady state. The noise performance of arm locking is calculated with the inclusion of the dominant expected noise sources: ultrastable oscillator (clock) noise, spacecraft motion, and shot noise. We find that clock noise and spacecraft motion limit the performance of dual arm locking in the LISA science band. Studying these issues reveals that although dual arm locking [A. Sutton and D. A. Shaddock, Phys. Rev. D 78, 082001 (2008)] has advantages over single (or common) arm locking in terms of allowing high gain, it has disadvantages in both laser frequency pulling and noise performance. We address this by proposing a modification to the dual arm-locking sensor, a hybrid of common and dual arm-locking sensors. This modified dual arm-locking sensor has the laser frequency pulling characteristics and low-frequency noise coupling of common arm locking, but retains the control system advantages of dual arm locking. We present a detailed design of an arm-locking controller and perform an analysis of the expected performance when used with and without laser prestabilization. We observe that the sensor phase changes beneficially near unity-gain frequencies of the arm-locking controller, allowing a factor of 10 more gain than previously believed, without degrading stability. With a time-delay error of 3 ns (equivalent of 1 m interspacecraft ranging error), time-delay interferometry (TDI) is capable of suppressing 300 Hz/?(Hz) of laser frequency noise to the required level. We show that if no interspacecraft laser links fail, arm locking alone surpasses this noise performance for the entire mission. If one interspacecraft laser link fails, arm locking alone will achieve this performance for all but approximately 1 h per year, when the arm length mismatch of the two remaining arms passes through zero. Therefore, the LISA sensitivity can be realized with arm locking and time-delay interferometry only, without any form of prestabilization.

2009-11-15

296

Labs drive the arms race  

Energy Technology Data Exchange (ETDEWEB)

The conviction of laboratory managers that high technology can provide safety and national security in a dangerous world and that technological solutions are paramount over political solutions has been a major driving force in perpetuating the nuclear arms race. The credo in the laboratories appears to be that there are never enough designs of nuclear weapons for deterrence so that there is always a need to develop such new ideas as the nuclear-pumped X-ray laser as a defense against energy missiles. The author outlines several alternative steps, including the ratification and reaffirmation of arms control treaties, negotiations, and a halt to the Star Wars program. A central point is to stop nuclear weapons testing. 7 references.

DeWitt, H.E.

1984-11-01

297

Regenerator cross arm seal assembly  

Science.gov (United States)

A seal assembly for disposition between a cross arm on a gas turbine engine block and a regenerator disc, the seal assembly including a platform coextensive with the cross arm, a seal and wear layer sealingly and slidingly engaging the regenerator disc, a porous and compliant support layer between the platform and the seal and wear layer porous enough to permit flow of cooling air therethrough and compliant to accommodate relative thermal growth and distortion, a dike between the seal and wear layer and the platform for preventing cross flow through the support layer between engine exhaust and pressurized air passages, and air diversion passages for directing unregenerated pressurized air through the support layer to cool the seal and wear layer and then back into the flow of regenerated pressurized air.

Jackman, Anthony V. (Indianapolis, IN)

1988-01-01

298

Synthesizing Grasps from Generalized Prototypes  

UK PubMed Central (United Kingdom)

This paper introduces a grasp synthesis algorithmthat can use any grasp prototype as the starting pointin a search for a good grasp. The algorithm makesthe given prototype more effective by generalizing itfor a specific task. This generalization step expandsthe range of application of the prototype to a widevariety of target object geometries, while ensuring thatthe resulting grasps are appropriate for the intendedtask. An example whole-hand grasp synthesized forthe Salisbury hand is shown at the end of the paper.1 IntroductionIt has been very difficult to successfully automatethe processes of acquiring and manipulating objectsusing today's robotic hands. Because many successfulgrasps are whole-hand, or enveloping grasps, onetempting solution is to develop prototypes, such asa generic cylinder grasp, to be applied to commonobjects, an approach motivated by studies of humangrasping (e.g. see Napier [17], and Jeannerod [10]).Prototype grasps benefit from requiring ver...

Nancy S. Pollard

299

Coenzyme Q10 synthesizing process  

UK PubMed Central (United Kingdom)

The coenzyme Q10 synthesizing process with coenzyme Q0 hydroquinone and isodecyl alcohol deca-isopentyl alcohol of purity not lower than 95 % as material includes dewatering and condensation reaction at room temperature under the catalysis of trifluoro methane sulfonic acid in no oxygen environment to obtain coenzyme Q10 hydroquinone, the oxidation of the reacted product without passing through any treatment with hydrogen peroxide and water solution of ferric trichloride to obtain crude coenzyme Q10 product, and crystallization of the crude coenzyme Q10 product in acetone to obtain yellow coenzyme Q10 product powder in content over 99 % and yield over 65 %. The present invention has simple operation, easy purification of the product, high yield, mild reaction condition, safe and controllable production process and industrial production value.

WANG GUOPING SHEN

300

Synthesizing Robust Systems with RATSY  

Directory of Open Access Journals (Sweden)

Full Text Available Specifications for reactive systems often consist of environment assumptions and system guarantees. An implementation should not only be correct, but also robust in the sense that it behaves reasonably even when the assumptions are (temporarily) violated. We present an extension of the requirements analysis and synthesis tool RATSY that is able to synthesize robust systems from GR(1) specifications, i.e., system in which a finite number of safety assumption violations is guaranteed to induce only a finite number of safety guarantee violations. We show how the specification can be turned into a two-pair Streett game, and how a winning strategy corresponding to a correct and robust implementation can be computed. Finally, we provide some experimental results.

Roderick Bloem; Hans-Jürgen Gamauf; Georg Hofferek; Bettina Könighofer; Robert Könighofer

2012-01-01

 
 
 
 
301

Synthesizing Customized Planners from Specifications  

CERN Document Server

Existing plan synthesis approaches in artificial intelligence fall into two categories -- domain independent and domain dependent. The domain independent approaches are applicable across a variety of domains, but may not be very efficient in any one given domain. The domain dependent approaches need to be (re)designed for each domain separately, but can be very efficient in the domain for which they are designed. One enticing alternative to these approaches is to automatically synthesize domain independent planners given the knowledge about the domain and the theory of planning. In this paper, we investigate the feasibility of using existing automated software synthesis tools to support such synthesis. Specifically, we describe an architecture called CLAY in which the Kestrel Interactive Development System (KIDS) is used to derive a domain-customized planner through a semi-automatic combination of a declarative theory of planning, and the declarative control knowledge specific to a given domain, to semi-autom...

Srivastava, B

1998-01-01

302

Method for synthesizing methyl benzoate  

UK PubMed Central (United Kingdom)

The invention discloses a method for synthesizing methyl benzoate. The method is characterized in that N,N-dimetbylformamide, tetraethylammonium iodide and bromobenzene are mixed, saturated with CO2 under normal pressure and then electrolyzed by constant current and the electrolyte is esterified and rotationally distilled to obtain the methyl benzoate. Compared with the prior art, the method has the advantages of simplicity, convenient and safe operation, easily obtained raw materials, low cost, high yield and no environment pollution, effectively utilize greenhouse-effect gas, namely the carbon dioxide, not only saves the production cost, but also greatly reduces the atmospheric pollution, relieve the problem that the energy is increasingly exhausted, has significance on environmental protection, and is a process route with industrial synthesis value.

JIAXING LU; JINGBO ZHANG; DONGFANG NIU; KAI ZHANG; GUIRONG ZHANG; HUAN WANG

303

Arms control and nonproliferation technologies  

Energy Technology Data Exchange (ETDEWEB)

This report includes information concerning: the Department of Energy's Office of Arms Control and Nonproliferation; the nuclear inspections in Iraq, lessons for verification; detection technologies needed for each step of nuclear weapon development; nuclear proliferation problems; strengthening the nuclear reactor fuel cycle against proliferation; monitoring using unattended remote nondestructive assay; seismic monitoring in a proliferation environment; forensic science center, remote infrared spectrometry for nonproliferation applications; and acoustic instrument for identifying chemical munitions.

Staehle, G.; Talaber, C.; Stull, S.

1992-01-01

304

Robot Arm Control Exploiting Natural Dynamics  

UK PubMed Central (United Kingdom)

This thesis presents an approach to robot arm control exploiting natural dynamics. The approachconsists of using a compliant arm whose joints are controlled with simple non-linear oscillators.The arm has special actuators which makes it robust to collisions and gives it a smooth compliantmotion. The oscillators produce rhythmic commands of the joints of the arm, and feedback of thejoint motions is used to modify the oscillator behavior. The oscillators enable the resonant propertiesof the arm to be exploited to perform a variety of rhythmic and discrete tasks. These tasks includetuning into the resonant frequencies of the arm itself, juggling, turning cranks, playing with a Slinkytoy, sawing wood, throwing balls, hammering nails and drumming.For most of these tasks, the controllers at each joint are completely independent, being coupledby mechanical coupling through the physical arm of the robot. The thesis shows that this mechanicalcoupling allows the oscillators to automat...

Rodney A. Brooks; Arthur C. Smith; Matthew M. Williamson

305

Coming clean in Bull Arm  

Energy Technology Data Exchange (ETDEWEB)

The environmental impacts of the Hibernia offshore drilling platform on the marine environment at Bull Arm, Newfoundland, were discussed. A rigidly controlled environmental monitoring program has been in effect since 1991. Eight sampling stations were chosen near the construction site and in the outer part of the arm. Six shallow and two deep water stations were established to collect samples of bottom sediment, near-bottom suspended sediment, blue mussels and winter flounder. Organic and inorganic tissue settling from the water column is measured. The rate of sediment accumulated and the quality of those sediments are monitored. Mussels and the liver enzyme system and gill tissue of winter flounder are known to be good indicators of possible contamination. The rigorous monitoring program to date resulted in a clean bill of health, i.e. the Hibernia project has not created any appreciable damage to the marine environment at Bull Arm. The monitoring program will be continued into the production phase on an annual basis until the year 2000, and biennially thereafter.

Anon.

1997-04-01

306

Regenerator cross arm seal assembly  

Energy Technology Data Exchange (ETDEWEB)

This patent describes improvement in a gas turbine engine having block means defining a pressurized air passage and a hot exhaust gas passage and a cross arm partition separating portions of the air and the exhaust passages, a regenerator disc on the block means intersecting the air and the exhaust passages and rotatable to transfer heat from the exhaust gas to the pressurized air and including an inboard surface, and rim seal means between the disc inboard surface and the block means operative to prevent pressurized air and exhaust gas leakage around the periphery of the disc. An improved cross arm seal assembly which comprises a platform generally coextensive with the cross arm partition disposed between the latter and the disc inboard surface, a porous and compliant support layer on a surface of the platform facing the disc inboard surface, a seal and wear layer on the support layer defining a barrier to gas passage and sealingly engaging the disc inboard surface, dike means between the seal and wear layer and the platform preventing communication through the support layer.

Jackman, A.V.

1988-01-26

307

Effects of unsupported arm training on arm exercise-related perception in COPD patients.  

UK PubMed Central (United Kingdom)

We hypothesized that arm training might affect unsupported arm exercise-related perception by decreasing motor output to arm/torso muscles in patients with chronic obstructive pulmonary disease (COPD). Eleven patients were studied at 80% of peak incremental arm exercise, before and after unsupported arm training. Training increased endurance time, decreased respiratory effort and much more arm effort (by Borg scale) without affecting chest wall dynamic hyperinflation or configuration. Ventilatory response to carbon dioxide output was the same before and after training so that at isotime the reduction in ventilation correlated strongly with a simultaneous reduction in metabolic output. These changes reflect a reduced ventilatory drive. We conclude that: (i) a reduced level of ventilation, relative to a decrease in central motor output, is the contribution of arm training to symptom alleviation during unsupported arm exercise in COPD patients, and (ii) arm training improved patients' exercise-related perception without affecting chest wall operational volumes or configuration.

Romagnoli I; Scano G; Binazzi B; Coli C; Bruni GI; Stendardi L; Gigliotti F

2013-03-01

308

Synthesis, Structure, and DNA Cleavage Properties of Copper(II) Complexes of 1,4,7-Triazacyclononane Ligands Featuring Pairs of Guanidine Pendants.  

UK PubMed Central (United Kingdom)

Two new ligands, L(1) and L(2), have been prepared via N-functionalization of 1,4,7-triazacyclononane (tacn) with pairs of ethyl- or propyl-guanidine pendants, respectively. The X-ray crystal structure of [CuL(1)](ClO(4))(2) (C1) isolated from basic solution (pH 9) indicates that a secondary amine nitrogen from each guanidine pendants coordinates to the copper(II) center in addition to the nitrogen atoms in the tacn macrocycle, resulting in a five-coordinate complex with intermediate square-pyramidal/trigonal bipyramidal geometry. The guanidines adopt an unusual coordination mode in that their amine nitrogen nearest to the tacn macrocycle binds to the copper(II) center, forming very stable five-membered chelate rings. A spectrophotometric pH titration established the pK(app) for the deprotonation and coordination of each guanidine group to be 3.98 and 5.72, and revealed that [CuL(1)](2+) is the only detectable species present in solution above pH ?8. The solution speciation of the CuL(2) complex (C2) is more complex, with at least 5 deprotonation steps over the pH range 4-12.5, and mononuclear and binuclear complexes coexisting. Analysis of the spectrophotometric data provided apparent deprotonation constants, and suggests that solutions at pH ?7.5 contain the maximum proportion of polynuclear complexes. Complex C1 exhibits virtually no cleavage activity toward the model phosphate diesters, bis(p-nitrophenyl)phosphate (BNPP) and 2-hydroxypropyl-p-nitrophenyl phosphate (HPNPP), while C2 exhibits moderate activity. For C2, the respective k(obs) values measured at pH 7.0 (7.24 (±0.08) × 10(-5) s(-1) (BNPP at 50 °C) and 3.2 (±0.3) × 10(-5) s(-1) (HPNPP at 25 °C)) are 40- and 10-times faster than [Cu(tacn)(OH(2))(2)](2+) complex. Both complexes cleave supercoiled pBR 322 plasmid DNA, indicating that the guanidine pendants of [CuL(1)](2+) may have been displaced from the copper coordination sphere to allow for DNA binding and subsequent cleavage. The rate of DNA cleavage by C2 is twice that measured for [Cu(tacn)(OH(2))(2)](2+), suggesting some degree of cooperativity between the copper center and guanidinium pendants in the hydrolysis of the phosphate ester linkages of DNA. A predominantly hydrolytic cleavage mechanism was confirmed through experiments performed either in the presence of various radical scavengers or under anaerobic conditions.

Tjioe L; Joshi T; Brugger J; Graham B; Spiccia L

2010-12-01

309

Oxidative addition/decarbonylation of. alpha. ,. omega. -alkanedioyl dichlorides. Metallacycle formation via intramolecular reductive cyclization of a pendant acid chloride with samarium(II) iodide  

Energy Technology Data Exchange (ETDEWEB)

Controlled oxidative addition and decarbonylation at one end of {alpha},{omega}-alkanedioyl dichlorides is reported with (Ph{sub 3}P){sub 2}Ir(N{sub 2})Cl, giving Ir(III) alkyl complexes bearing a pendant acid chloride functionality. The use of the dinitrogen complex enables suppression of competitive intramolecular lactonization processes. Use of 2 equiv of samarium(II) diiodide uniquely promotes intramolecular reductive cyclometalation of one of these complexes, forming a cyclic acyl complex. This cyclization is highly sensitive to both electronic factors in the substrate and the nature and stoichiometry of the reducing agent.

Zizelman, P.M.; Stryker, J.M. (Indiana Univ., Bloomington (USA))

1990-06-01

310

Assistant template and co-template agents in modeling mesoporous silicas and post-synthesizing organofunctionalizations  

Science.gov (United States)

Mesoporous SBA-16 silicas were synthesized through a direct methodology using the template (F127) combined with co-templates (ethanol and n-butanol), with tetraethylorthosilicate as the silica source. These ordered mesoporous silica were characterized by elemental analyses, infrared spectroscopy, solid-state nuclear magnetic resonance for 13C (CP/MAS) and 29Si (HP/DEC) nuclei, nitrogen sorption/desorption processes, small angle X-ray analyses (SAXS) and transmission electron microscopy (TEM). SAXS and TEM results confirmed the space group Im3m and cubic 3D symmetry, typical for highly ordered SBA-16. The sorption/desorption data for SBA-16 and when functionalized gave type IV isotherms, with hysteresis loop H2. Surface areas of 836; 657 and 618 m2 g?1 and average pore diameters of 7.99; 8.10 and 9.85 nm, for SBA-16A, SBA-16B and SBA-16C were obtained, respectively. When functionalized the silicas presented a reduction in surface area, pore volume and pore diameter due to the pendant chains that interfere with nitrogen sorption in these measurements. The co-template ethanol favors the ordered mesopores with highest wall thicknesses.

Oliveira, Vaeudo V.; Airoldi, Claudio

2012-12-01

311

Process for synthesizing paliperidone intermediate  

UK PubMed Central (United Kingdom)

The invention relates to a method for synthesizing an important intermediate of paliperidone. The method relates to the intermediate of 3-(2-chloroethyl)-6, 7, 8, 9-tetrahydrochysene-9-oxhydryl-2-methyl-4H-pyridino-(1, 2-a)pyrimidine-4-kektone, and comprises: step one, in a solvent, catalytically cyclizing 2-amido-3-oxhydryl-pyridine and alpha-acetyl-gamma-butyrolactone by acid to obtain a compound 3 step two, in the solvent, catalytically hydrogenating a pyridine ring of the compound 3 by a transitional metal catalyst to obtain a compound 4 and step three, in the solvent, selectively chlorinating primary alcohol of the compound 4 by a chlorination reagent to obtain the intermediate of the paliperidone 3-(2-chloroethyl)-6, 7, 8, 9-tetrahydrochysene-9-oxhydryl-2-methyl-4H-pyridino-(1, 2-a)pyrimidine-4-kektone. The method has the characteristics of high selectivity and easy operation a product and the intermediate can be easily separated and purified and a compound 1 and a compound 2 can be cyclized completely.

HONGYUN GAO; WENQIAO LI; FANGJIANG ZHANG

312

Method for synthesizing oxime ether  

UK PubMed Central (United Kingdom)

The invention discloses a method for synthesizing oxime ether. The method includes the steps of: adding 1 mol portion of ketoxime in 1- butyl-3- methylimidazole tetrafluoroborate of which the adding amount is 2-20 times of the weight of the ketoxime then adding 1.05-2.6 mol portions of alkali, dripping 1-1.3 mol portions of alkylating agent at the temperature of 0-50 DEG C within 0.5-2h after dripping, reacting for 0.5-2h with the temperature preserved then filtering, adding ether which is 5-20 times of the weight of the 1-butyl-3- methylimidazole tetrafluoroborate in the filtrate and extracting respectively for 4-8 times combining the upper layer of extraction liquid, recovering ether solvent through distillation and finally conducting rectification separation to obtain the product. The method adopts ion liquid as reaction solvent, which is not volatile, does not generate harmful gas and wastewater, and improves the operation environment. The process is simple, the post treatment investment is low, and the cost is saved as the ion liquid can be recycled, the method is a green technology and the product is high in yield and good in quality.

SHENGJIAN ZHANG; SHU LUO; HONG ZHANG; ZHENPING SHAO; YUANQING SHI; HONGLEI MAO

313

Catalyst for synthesizing 3-pentanone  

UK PubMed Central (United Kingdom)

The invention relates to a catalyst for synthesizing 3-pentanone, and belongs to the technical field of preparation of catalysts for fine chemical products. The catalyst consists of an active composition, an auxiliary agent and a carrier, wherein the active composition is one or more of lanthanum rare earth oxide and actinium rare earth oxide the carrier is one or more of zirconia, alumina, titania and silicon dioxide the weight ratio of the active composition to the carrier is 5-80:95-20 and the auxiliary agent is one or more alkali metals or alkaline earth oxides and is 0.1 to 5 weight percent of the total weight of the active composition and the carrier. The catalyst not only maintains the activity of the prior catalyst, but also overcomes the defects of the prior rare earth catalyst, achieves the aims of inhibiting the isomerization reaction and reducing the content of 2-pentanone and methyl isopropyl ketone in the reaction products, and greatly reduces the separation difficulty of the 3-pentanone.

HENGXIU WANG; WEIBIN CHEN; RONGQUN LU; ZHENJUAN HE; JIANQIANG GE

314

Coke Formation During Hydrocarbons Pyrolysis. Part One: Steam Cracking Formation de coke pendant la pyrolise des hydrocarbures. Première partie : vapocraquage  

Directory of Open Access Journals (Sweden)

Full Text Available Thermal cracking is always accompanied by coke formation, which becomes deposited on the wall and limits heat transfers in the reactor while increasing pressure drops and possibly even plugging up the reactor. This review article covers undesirable coking operations in steam craking reactors. These coking reactions may take place in the gas phase and/or on the surface of the reactor, with coke being produced during pyrolysis by a complex mechanism that breaks down into a catalytic sequence and a noncatalytic sequence. After a brief description of different experimental set-ups used to measure the coke deposition, on the basis of research described in the literature, the different factors and their importance for coke formation are listed. In particular, we describe the effects of surface properties of stainless-steel and quartz reactors as well as the influence of the cracked feedstock, of temperature, of dilution, of residence time and of the conversion on coke deposition. Some findings about the morphology of coke are described and linked to formation mechanisms. To illustrate this review, some particularly interesting research is referred to concerning models developed to assess coke formation during propane steam cracking. Le craquage thermique est toujours accompagné de la formation de coke qui, en se déposant à la paroi, limite les transferts de chaleur au réacteur, augmente les pertes de charges et même peut boucher celui-ci. Cet article fait le point sur les réactions indésirables de cokage dans les réacteurs de vapocraquage. Ces réactions de cokage peuvent avoir lieu en phase gazeuse et/ou sur la surface du réacteur, le coke étant produit pendant la pyrolyse par un mécanisme complexe qui se décompose en une séquence catalytique et une séquence non catalytique. Après une brève présentation des différents montages expérimentaux utilisés pour mesurer le dépôt de coke, il est mentionné, à partir de travaux de la littérature, les différents facteurs et leur importance sur la formation du coke. On présentera en particulier les effets de propriétés de surface de réacteurs en inox et en quartz, ainsi que l'influence de la charge craquée, de la température, de la dilution, du temps de séjour et de la conversion sur les dépôts de coke. Quelques résultats sur la morphologie du coke seront présentés et reliés aux mécanismes de formation du coke. Pour illustrer ce travail, on reprendra quelques études particulièrement intéressantes sur des modèles d'évaluation de la formation de coke développés pour le vapocraquage de propane.

Weill J.; Broutin P.; Billaud F.; Gueret C.

2006-01-01

315

International security and arms control  

Energy Technology Data Exchange (ETDEWEB)

The impact of arms control and nuclear strategy issues on the relationship between the United States and the Soviet Union is examined. Based on a conference held at Emory University, this book's contributors include former Presidents Ford and Carter, as well as Henry Kissinger, Anatoly Dobrynin, and other current or former important American and foreign government officials and academic experts. They explore the interaction between regional conflicts and superpower policies, how new technologies affect the status quo, and the past record and future prospects for negotiations.

Mickiewicz, E.P.; Kolkowicz, R.

1986-01-01

316

Dual arm master controller concept  

International Nuclear Information System (INIS)

[en] The Advanced Servomanipulator (ASM) slave was designed with an anthropomorphic stance, gear/torque tube power drives, and modular construction. These features resulted in increased inertia, friction, and backlash relative to tape-driven manipulators. Studies were performed which addressed the human factors design and performance trade-offs associated with the corresponding master controller best suited for the ASM. The results of these studies, as well as the conceptual design of the dual arm master controller, are presented. 6 references, 3 figures

1984-01-01

317

Dual arm master controller development  

International Nuclear Information System (INIS)

[en] The advanced servomanipulator (ASM) slave was designed with an anthropomorphic stance, gear/torque tube power drives, and modular construction. These features resulted in increased inertia, friction, and backlash relative to tape-driven manipulators. Studies were performed which addressed the human factors design and performance trade-offs associated with the corresponding master controller best suited for the ASM. The results of these studies, as well as the conceptual design of the dual arm master controller, are presented. This work was performed as part of the Consolidated Fuel Reprocessing Program at the Oak Ridge National Laboratory. 5 refs., 7 figs., 1 tab

1985-01-01

318

Right says arms control wrong  

Energy Technology Data Exchange (ETDEWEB)

This article asserts that the conservative right wing of the Republican party is in the midst of an attack on arms control in general, intent on sabotage of the treaties at the core of the program - the 1972 Anti-Ballistic Missile Treaty, and the 1991 and 1993 START treaties, and treaties in negotiation at present. The author argues that this part of the political party is far right of other conservatives, and is intent on unravelling all progress made to this pont in time.

Isaacs, J. [Council for a Livable World, Washington, DC (United States)

1995-09-01

319

Synthesis and application of novel multi-arm poly(carboxylic acid)s for glass-ionomer restoratives.  

Science.gov (United States)

We have developed a novel glass-ionomer cement system composed of multi-arm poly(acrylic acid-co-itaconic acid)s. These polyacids were synthesized via a chain-transfer polymerization reaction using newly synthesized multi-arm chain-transfer agents. The cements formulated with the multi-arm polyacids showed significantly lower viscosities in water as compared to those formulated with the linear polyacids. Due to the lower viscosities, the MW of the polyacids can be significantly increased for enhanced mechanical strengths, while keeping the ease of mixing and handling. The experimental cements showed significantly improved compressive strengths as compared to Fuji II after aged in water for 3 months. PMID:19033326

Xie, Dong; Zhao, Jun; Weng, Yiming

2008-11-25

320

Synthesis and application of novel multi-arm poly(carboxylic acid)s for glass-ionomer restoratives.  

UK PubMed Central (United Kingdom)

We have developed a novel glass-ionomer cement system composed of multi-arm poly(acrylic acid-co-itaconic acid)s. These polyacids were synthesized via a chain-transfer polymerization reaction using newly synthesized multi-arm chain-transfer agents. The cements formulated with the multi-arm polyacids showed significantly lower viscosities in water as compared to those formulated with the linear polyacids. Due to the lower viscosities, the MW of the polyacids can be significantly increased for enhanced mechanical strengths, while keeping the ease of mixing and handling. The experimental cements showed significantly improved compressive strengths as compared to Fuji II after aged in water for 3 months.

Xie D; Zhao J; Weng Y

2010-01-01

 
 
 
 
321

The performance of arm locking in LISA  

CERN Multimedia

For the laser interferometer space antenna (LISA) to reach it's design sensitivity, the coupling of the free running laser frequency noise to the signal readout must be reduced by more than 14 orders of magnitude. One technique employed to reduce the laser frequency noise will be arm locking, where the laser frequency is locked to the LISA arm length. This paper details an implementation of arm locking, studies orbital effects, the impact of errors in the Doppler knowledge, and noise limits. The noise performance of arm locking is calculated with the inclusion of the dominant expected noise sources: ultra stable oscillator (clock) noise, spacecraft motion, and shot noise. Studying these issues reveals that although dual arm locking [A. Sutton & D. A Shaddock, Phys. Rev. D 78, 082001 (2008).] has advantages over single (or common) arm locking in terms of allowing high gain, it has disadvantages in both laser frequency pulling and noise performance. We address this by proposing a hybrid sensor, retaining th...

McKenzie, Kirk; Shaddock, Daniel A

2009-01-01

322

ATHLETIC BRACE FOR THE LOWER ARM  

UK PubMed Central (United Kingdom)

A brace (16) for protecting the lower arm, particularly the base joint of the thumb, during a fall. The brace (16) includes a main body (2), a sheath (10), and a plurality of straps (18). The main body (2) substantially follows the contour of the underside of the lower arm and has an open upper section. The sheath (10) defines a bore (12), and is attached to the main body (2) so as to allow the thumb to fit within the bore. The straps (18) traverse the open upper section of the main body (2) to secure the brace to the lower arm. The main body (2) and the sheath (10) strapped to the lower arm provide protection to the lower arm in the event of a fall. The brace is intended for use in any activity that can result in injury to the lower arm, and base joint of the thumb such as skateboarding, snow boarding, skiing, and roller blade.

HAHN Giora; MORRIS John G. Jr.

323

Nuclear arms control: Background and issues  

Energy Technology Data Exchange (ETDEWEB)

The authors present an in-depth history of the major arms control negotiations between the superpowers. From the SALT negotiations to the possibility of an arms race in space, the report shows, in nontechnical terms, how the United States and the Soviet Union arrived at their present positions - and where they might go from here. Texts of all the major arms control agreements are included.

1985-01-01

324

How Many Noses Are in Your Arm?  

Science.gov (United States)

In this math lesson, learners apply the concepts of ratio and proportion to determine the length of the Statue of Liberty's torch-bearing arm. Learners use chart paper, string, and rulers to estimate the length of the statue's arm based on the knowledge that the nose is 4 feet 6 inches. The actual length of the Statue of Liberty's arm is located in an almanac (or online) and compared to the learners' estimates.

Pbs

2012-01-01

325

Position Teaching of a Robot Arm by  

UK PubMed Central (United Kingdom)

This paper describes the first prototype of a "Programmingby demonstration" (PbD) system for positionteaching of a robot manipulator. A new approachfor enabling PbD using supervised learning ispresented, by connecting a wearable input device forsensing human arm movements to the software controllerof a robot arm. The method does not requireanalytical modelling of either the human arm or robot,and can be customised for di#erent users and robots.Initial experiments on some simple movements tasksare presented.

Jacopo Aleotti; Er Skoglund; Tom Duckett

326

Biodegradable functional poly(ester amide)s with pendant hydroxyl functional groups: synthesis, characterization, fabrication and in vitro cellular response.  

UK PubMed Central (United Kingdom)

The synthesis of a new family of biodegradable ?-amino acid poly(ester amide)s (AA-PEAs) with pendant benzyl ether groups and hydroxyl functional groups is reported. The synthetic strategy employs the ring opening reaction of O-benzyl-L-serine-N-carboxyanhydride with di-p-toluenesulfonic acid salts of bis-L-valine butane-1,4-diester, followed by solution polycondesation reactions with di-p-nitrophenyl sebacate in N,N-dimethylacetamide. Catalytic hydrogenation of the resulting benzyl ether protected AA-PEAs (PEA-Ser-Bzs) was performed to restore the hydroxyl functional groups in the functionalized AA-PEAs (PEA-Ser-OH). All resulting polymers were characterized by standard physico-chemical methods. The pendant hydroxyl groups in PEA-Ser-OH were used to fabricate AA-PEA-based gels via acrylation and photo-gelation. The cell-polymer interactions of PEA-Ser-Bz and PEA-Ser-OH were evaluated in terms of cell attachment and proliferation assay using bovine aortic endothelial cells (BAECs) as well as fibroblasts. The cell culture data indicated that the hydrophobic/hydrophilic characteristics (from contact angle data) of these AA-PEAs could significantly affect the interaction between BAECs and AA-PEA. This finding may provide additional possible applications for this new family of functionalized AA-PEA polymers.

Deng M; Wu J; Reinhart-King CA; Chu CC

2011-04-01

327

Linear versus Dendritic Molecular Binders for Hydrogel Network Formation with Clay Nanosheets: Studies with ABA Triblock Copolyethers Carrying Guanidinium Ion Pendants.  

UK PubMed Central (United Kingdom)

ABA-triblock copolyethers 1a-1c as linear polymeric binders, in combination with clay nanosheets (CNSs), afford high-water-content moldable supramolecular hydrogels with excellent mechanical properties by constructing a well-developed crosslinked network in water. The linear binders carry in their terminal A blocks guanidinium ion (Gu(+)) pendants for adhesion to the CNS surface, while their central B block comprises poly(ethylene oxide) (PEO) that serves as a flexible linker for adhered CNSs. Although previously reported dendritic binder 2 requires multistep synthesis and purification, the linear binders can be obtained in sizable quantities from readily available starting materials by controlled polymerization. Together with dendritic reference 2, the modular nature of compounds 1a-1c with different numbers of Gu(+) pendants and PEO linker lengths allowed for investigating how their structural parameters affect the gel network formation and hydrogel properties. The newly obtained hydrogels are mechanically as tough as that with 2, although the hydrogelation takes place more slowly. Irrespective of which binder is used, the supramolecular gel network has a shape-memory feature upon drying followed by rewetting, and the gelling water can be freely replaced with ionic liquids and organic fluids, affording novel clay-reinforced iono- and organogels, respectively.

Tamesue S; Ohtani M; Yamada K; Ishida Y; Spruell JM; Lynd NA; Hawker CJ; Aida T

2013-09-01

328

A non-gradient based algorithm for the determination of surface tension from a pendant drop: application to low Bond number drop shapes.  

UK PubMed Central (United Kingdom)

The pendant drop method is one of the most widely used techniques to measure the surface tension between gas-liquid and liquid-liquid interfaces. The method consists of fitting the Young-Laplace equation to the digitized shape of a drop suspended from the end of a capillary tube. The first use of digital computers to solve this problem utilized nonlinear least squares fitting and since then numerous subroutines and algorithms have been reported for improving efficiency and accuracy. However, current algorithms which rely on gradient based methods have difficulty converging for almost spherical drop shapes (i.e. low Bond numbers). We present a non-gradient based algorithm based on the Nelder-Mead simplex method to solve the least squares problem. The main advantage of using a non-gradient based fitting routine is that it is robust against poor initial guesses and works for almost spherical bubble shapes. We have tested the algorithm against theoretical and experimental drop shapes to demonstrate both the efficiency and the accuracy of the fitting routine for a wide range of Bond numbers. Our study shows that this algorithm allows for surface tension measurements corresponding to Bond numbers previously shown to be ill suited for pendant drop measurements.

Alvarez NJ; Walker LM; Anna SL

2009-05-01

329

Letter report: Ari Patrinos -- ARM summary  

Energy Technology Data Exchange (ETDEWEB)

This letter report provides a summary of the authors` views on ARM. ARM is a highly focused program designed to improve understanding of the transport of infrared and solar radiation through the atmosphere. The program pays particular attention to the interaction of radiation with the three phases of water. The goals of ARM are usually articulated in terms of improvements in climate models. The authors agree that ARM can indeed make significant contributions to the understanding of climate change. In addition they believe that the results of the program will have wide applicability to a broad range of problems, including more accurate short-term and seasonal weather forecasting.

MacDonald, G.J.; Ruderman, M.A.; Treiman, S.B.

1995-07-27

330

Low friction high speed rocker arm  

Energy Technology Data Exchange (ETDEWEB)

A valve train is described for an internal combustion engine comprising, a camshaft mounted close above the cylinder head face of the engine, a one-piece essentially U-shaped rocker arm mounted above the camshaft for an arcuate movement and defined by a bottom wall integral with a pair of laterally spaced upstanding side walls. The bottom wall has a cylindrical fulcrum surface projecting upwardly. A lash adjuster fixedly supports above the rocker arm against lateral movement and has a lower surface engaging the cylindrical fulcrum surface with a contact establishing a pure rolling motion without friction of the rocker arm upon the lash adjuster lower surface. A reciprocatingly mounted valve stem engages one end of the rocker arm for reciprocation of the valve. The other end of the rocker arm rotatably supports a dual function roller engagable with a cam lobe on the camshaft for arcuate pivoting of the rocker arm about its fulcrum upon rotation of the camshaft. Support means supports the roller for both an arcuate movement of its axis of rotation along a predetermined path providing a pure rolling motion of the rocker arm about its fulcrum upon the lash adjuster surface. This confines the roller and arm in a manner preventing a longitudinal sliding movement of the rocker arm fulcrum surface relative to the lash adjuster surface.

Simko, A.O.

1987-07-28

331

Quantifying arm nonuse in individuals poststroke.  

UK PubMed Central (United Kingdom)

BACKGROUND: Arm nonuse, defined as the difference between what the individual can do when constrained to use the paretic arm and what the individual does when given a free choice to use either arm, has not yet been quantified in individuals poststroke. OBJECTIVES: (1) To quantify nonuse poststroke and (2) to develop and test a novel, simple, objective, reliable, and valid instrument, the Bilateral Arm Reaching Test (BART), to quantify arm use and nonuse poststroke. METHODS: First, we quantify nonuse with the Quality of Movement (QOM) subscale of the Actual Amount of Use Test (AAUT) by subtracting the AAUT QOM score in the spontaneous use condition from the AAUT QOM score in a subsequent constrained use condition. Second, we quantify arm use and nonuse with BART by comparing reaching performance to visual targets projected over a 2D horizontal hemi-work space in a spontaneous-use condition (in which participants are free to use either arm at each trial) with reaching performance in a constrained-use condition. RESULTS: All participants (N = 24) with chronic stroke and with mild to moderate impairment exhibited nonuse with the AAUT QOM. Nonuse with BART had excellent test-retest reliability and good external validity. CONCLUSIONS: BART is the first instrument that can be used repeatedly and practically in the clinic to quantify the effects of neurorehabilitation on arm use and nonuse and in the laboratory for advancing theoretical knowledge about the recovery of arm use and the development of nonuse and "learned nonuse" after stroke.

Han CE; Kim S; Chen S; Lai YH; Lee JY; Osu R; Winstein CJ; Schweighofer N

2013-06-01

332

MODELING AND SIMULATION OF ROBOTIC HUMANOID ARM  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper block model and machine model of Robotic humanoid arm has been generated Using MATLAB Simulink. Equations of Kinematics are derived by using D-H notation. By this equation and inverse kinematicsparameters for the motion trajectory have been determined. Kinematic parameters are divided into two groups namely, link parameters and joint parameters. Geometric model and motion of robotic humanoid arm with two link model with 3 Degree of freedom and arm with palm and fingers with 18 degree of freedom has been realized. Virtual simulation of the arm is also first step in actually controlling the mechanical structure.

RANJEET RANJAN; DR. ARBIND KUMAR; DR. PRAVEEN DHYANI

2012-01-01

333

Approach to naval arms control. Final report  

Energy Technology Data Exchange (ETDEWEB)

This paper brings a holistic appreciation of the problems and opportunities of arms control to the particular issue-area of proposals for naval arms control. This multi-level analysis treats what may be characterized as the policy, strategic, operational, tactical, and technological areas of concern--all with reference to national and international security. Two principal purposes drive this analysis: first, to provide a conceptual framework suitable for the assessment of naval arms control; and second to review briefly some leading proposals for naval arms control.

Gary, C.S.

1990-07-01

334

Arms control, strategic stability, and global security  

Energy Technology Data Exchange (ETDEWEB)

After some brief prefatory remarks on terrorism, Secretary Shultz reviews past negotiations on arms control. He then discusses the US objectives in arms control and the US proposal (then on the table at Geneva), including: strategic arms reduction; intermediate-range nuclear forces; and defense and space arms. In commenting on the Soviet counterproposal, Secretary Schultz warns that the Soviets are practitioners of vague, superficially attractive proposals like non-use of force, no-first-use of nuclear weapons, or nuclear-freeze zones. He concludes by summarizing briefly the prospects.

Shultz, G.

1985-01-01

335

Wilcox molecular torsion balance with rigid side arm and separable atropisomers for investigating CH-? interactions.  

UK PubMed Central (United Kingdom)

A new variant of the Wilcox molecular torsion balance featuring a naphthyl-alkyl side arm was synthesized. The energy barrier for axial isomerization in the new balance was sufficiently high to allow for separation of the two rotamers and to observe their isomerization kinetics. The CH-? interaction energies in derivatives of the new and the original ester balance were in close agreement, suggesting that the motion in ester linkage is not an important factor in folding in the ester balance.

Bhayana B

2013-07-01

336

Photochemical activation of ruthenium(II)-pyridylamine complexes having a pyridine-N-oxide pendant toward oxygenation of organic substrates.  

UK PubMed Central (United Kingdom)

Ruthenium(II)-acetonitrile complexes having ?(3)-tris(2-pyridylmethyl)amine (TPA) with an uncoordinated pyridine ring and diimine such as 2,2'-bipyridine (bpy) and 2,2'-bipyrimidine (bpm), [Ru(II)(?(3)-TPA)(diimine)(CH(3)CN)](2+), reacted with m-chloroperbenzoic acid to afford corresponding Ru(II)-acetonitrile complexes having an uncoordinated pyridine-N-oxide arm, [Ru(II)(?(3)-TPA-O)(diimine)(CH(3)CN)](2+), with retention of the coordination environment. Photoirradiation of the acetonitrile complexes having diimine and the ?(3)-TPA with the uncoordinated pyridine-N-oxide arm afforded a mixture of [Ru(II)(TPA)(diimine)](2+), intermediate-spin (S = 1) Ru(IV)-oxo complex with uncoordinated pyridine arm, and intermediate-spin Ru(IV)-oxo complex with uncoordinated pyridine-N-oxide arm. A Ru(II) complex bearing an oxygen-bound pyridine-N-oxide as a ligand and bpm as a diimine ligand was also obtained, and its crystal structure was determined by X-ray crystallography. Femtosecond laser flash photolysis of the isolated O-coordinated Ru(II)-pyridine-N-oxide complex has been investigated to reveal the photodynamics. The Ru(IV)-oxo complex with an uncoordinated pyridine moiety was alternatively prepared by reaction of the corresponding acetonitrile complex with 2,6-dichloropyridine-N-oxide (Cl(2)py-O) to identify the Ru(IV)-oxo species. The formation of Ru(IV)-oxo complexes was concluded to proceed via intermolecular oxygen atom transfer from the uncoordinated pyridine-N-oxide to a Ru(II) center on the basis of the results of the reaction with Cl(2)py-O and the concentration dependence of the consumption of the starting Ru(II) complexes having the uncoordinated pyridine-N-oxide moiety. Oxygenation reactions of organic substrates by [Ru(II)(?(3)-TPA-O)(diimine)(CH(3)CN)](2+) were examined under irradiation (at 420 ± 5 nm) and showed selective allylic oxygenation of cyclohexene to give cyclohexen-1-ol and cyclohexen-1-one and cumene oxygenation to afford cumyl alcohol and acetophenone.

Kojima T; Nakayama K; Sakaguchi M; Ogura T; Ohkubo K; Fukuzumi S

2011-11-01

337

Photochemical activation of ruthenium(II)-pyridylamine complexes having a pyridine-N-oxide pendant toward oxygenation of organic substrates.  

Science.gov (United States)

Ruthenium(II)-acetonitrile complexes having ?(3)-tris(2-pyridylmethyl)amine (TPA) with an uncoordinated pyridine ring and diimine such as 2,2'-bipyridine (bpy) and 2,2'-bipyrimidine (bpm), [Ru(II)(?(3)-TPA)(diimine)(CH(3)CN)](2+), reacted with m-chloroperbenzoic acid to afford corresponding Ru(II)-acetonitrile complexes having an uncoordinated pyridine-N-oxide arm, [Ru(II)(?(3)-TPA-O)(diimine)(CH(3)CN)](2+), with retention of the coordination environment. Photoirradiation of the acetonitrile complexes having diimine and the ?(3)-TPA with the uncoordinated pyridine-N-oxide arm afforded a mixture of [Ru(II)(TPA)(diimine)](2+), intermediate-spin (S = 1) Ru(IV)-oxo complex with uncoordinated pyridine arm, and intermediate-spin Ru(IV)-oxo complex with uncoordinated pyridine-N-oxide arm. A Ru(II) complex bearing an oxygen-bound pyridine-N-oxide as a ligand and bpm as a diimine ligand was also obtained, and its crystal structure was determined by X-ray crystallography. Femtosecond laser flash photolysis of the isolated O-coordinated Ru(II)-pyridine-N-oxide complex has been investigated to reveal the photodynamics. The Ru(IV)-oxo complex with an uncoordinated pyridine moiety was alternatively prepared by reaction of the corresponding acetonitrile complex with 2,6-dichloropyridine-N-oxide (Cl(2)py-O) to identify the Ru(IV)-oxo species. The formation of Ru(IV)-oxo complexes was concluded to proceed via intermolecular oxygen atom transfer from the uncoordinated pyridine-N-oxide to a Ru(II) center on the basis of the results of the reaction with Cl(2)py-O and the concentration dependence of the consumption of the starting Ru(II) complexes having the uncoordinated pyridine-N-oxide moiety. Oxygenation reactions of organic substrates by [Ru(II)(?(3)-TPA-O)(diimine)(CH(3)CN)](2+) were examined under irradiation (at 420 ± 5 nm) and showed selective allylic oxygenation of cyclohexene to give cyclohexen-1-ol and cyclohexen-1-one and cumene oxygenation to afford cumyl alcohol and acetophenone. PMID:21942283

Kojima, Takahiko; Nakayama, Kazuya; Sakaguchi, Miyuki; Ogura, Takashi; Ohkubo, Kei; Fukuzumi, Shunichi

2011-10-13

338

Friction reducing rocker arm construction  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a friction reducing engine rocker arm construction. It comprises: a rocker arm having a longitudinally extending body, the body having an opening therein at least partially circular in shape and defined by an annular wall portion of the body, a fulcrum having a mating portion at least partially circular in shape. The fulcrum being rotatably mounted in the opening with a slight radial clearance space between the wall and fulcrum, cam means having a no-load base circle portion and a load contoured portion. The cam means being engageable with the body to pivot the same about the fulcrum. The cam means is under no-load condition when contact between the cam means and body is made on the base circle portion of the cam means, the cam means loads the body into contact with and against one side of the fulcrum, and lubricant inlet means to supply lubricant under pressure to the clearance space at a pressure level greater than the no-load force of the body against the fulcrum.

Willermet, P.A.; Pieprzak, J.M.

1990-01-01

339

Mobile C-arm units  

Energy Technology Data Exchange (ETDEWEB)

Mobile C-arm units, so named because of their configuration, are used primarily for fluoroscopic imaging during surgical, orthopedic, critical care, and emergency care procedures. They also provide radiographic capability, although they are rarely used for this imaging modality. We evaluated three mobile C-arm units from three manufacturers. We based our ratings on the ability of the units to safely and reliably produce the best possible image quality while delivering the lowest possible radiation dose to the patient and protecting personnel from radiation exposure; we also considered human factors design. The Philips BV 25 N is rated Acceptable and is preferred as a general-purpose unit. The OEC-Diasonics 9000/6 is also rated Acceptable and may be preferred when the hospital has specific uses for its optional specialty modules. The Fischer Ortho-Omni 325 is rated Acceptable-Not Recommended because of its relatively high patient exposure rates, poorer object thickness compensation (penetration) capability, poorer spatial resolution, and overall poor human factors design compared with the other evaluated units. Also see Issues of Radiation Exposure and Ensuring Optimum Performance.

1990-08-01

340

Use of snake arm robots  

International Nuclear Information System (INIS)

The Swedish Ringhals nuclear power station is the most powerful nuclear power plant in Sweden, with an installed cumulated power of the four units of 3,560 MW. Ringhals 1 is an 830 MW boiling water reactor by ABB; the other three units are pressurized water reactors. In the revision in summer of 2003, Ringhals 1 showed a leakage in one of the scram rods. The operator decided to continue plant operation at a reduced power level and develop concepts for repair, should this become necessary. The technical challenge was posed by rhe repair of the second bank of control rods. A section of the shroud of the defective scram rod had to be replaced. After examination of the bids, the contract was awarded to the Swedish Uddcomb Engineering AB, which cooperated with OC-Robotics and Climax Machine Tools Inc. The consortium proposed to perform the necessary repair work by means of 2 so-called snake arm robots. Repair was completed successfully in the course of the 2004 revision outage. Both snake arm robots fully met all expectations. The entire process, pipe repair included, was carried out within the scheduled period of three days. (orig.)

2008-01-01

 
 
 
 
341

Navy autonomy thwarts arms control  

Energy Technology Data Exchange (ETDEWEB)

During the past three decades the two superpowers have steadily modernized their naval forces, sent large numbers of nuclear weapons to sea, and engaged in provocative and potentially destabilizing operations. Currently the US is deploying new aircraft carriers, a new generation of fighter aircraft, and new surface ships with greater offensive and defensive power. The Soviet Union has deployed a new generation of attack submarines and is completing its first large aircraft carrier. And the Soviets are preparing to follow the US lead in deploying long-range, highly accurate sea-launched cruise missiles. These developments, accompanied by naval operations that increase the potential for superpower conflict at sea, should make naval arms control a high priority. But it has not been a focus of US-Soviet negotiations and only recently has garnered more interest from multilateral disarmament bodies. An examination of the record shows that bilateral efforts in this area have been minimal and impeded by strong opposition, particularly from the US Navy. The multilateral approach may be more promising because of five agreements affecting the seas that could offer precedents, but this will require improved coordination between the arms control and law of the sea processes. 10 references.

Arkin, W.M.

1987-09-01

342

Stress analysis for robot arm version 2  

International Nuclear Information System (INIS)

The design of a robot needs to be analyzed to ensure the specification and requirement by the user is full filled. Therefore, stress analysis has been performed on the robot arm version 2 after its complete fabrication. This paper discusses the result of the analysis and proposed measures to improve the future design of robot arm. (author)

2010-01-01

343

Firm exit and armed conflict in Colombia  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper uses two unique panel data sets to study the causal effect that armed conflict has over entrepreneurial activity in Colombia. Using a fixed effect estimation methodology at the plant level and controlling for the possible endogeneity of armed conflict through the use of instrumental varia...

Camacho, Andriana; Rodriguez, Catherine

344

Why we cannot grow a human arm.  

Science.gov (United States)

There are several significant issues that prevent us from growing a human arm now, or within the next 10-20 years. From a tissue engineering perspective, while we can grow many of the components necessary for construction of a human arm, we can only grow them in relatively small volumes, and when scaled up to large volumes we lack the ability to develop adequate blood/nerve supply. From a genetic engineering perspective, we will probably never be able to turn on the specific genes necessary to "grow an arm" unless it is attached to a fetus and this presents enormous ethical issues related to farming of human organs and structures. Perhaps the most daunting problem facing the transplantation of a tissue engineered or transplanted arm is that of re-innervation of the structure. Since the sensory and motor nerve cells of the arm are located outside of the structure, re-innervation requires those nerves to regenerate over relatively large distances to repopulate the nervous system of the arm. This is something with which we have had little success. We can grow repair parts, but "growing an arm" presents too many insurmountable problems. The best we could possibly do with tissue engineering or genetic engineering would be the equivalent of a fetal arm and the technical problems, costs, and ethical hurdles are enormous. A more likely solution is a functional, permanent, neuroelectronically-controlled prosthesis. These are nearly a reality today. PMID:24113888

Ricci, John L

2013-10-10

345

Why we cannot grow a human arm.  

UK PubMed Central (United Kingdom)

There are several significant issues that prevent us from growing a human arm now, or within the next 10-20 years. From a tissue engineering perspective, while we can grow many of the components necessary for construction of a human arm, we can only grow them in relatively small volumes, and when scaled up to large volumes we lack the ability to develop adequate blood/nerve supply. From a genetic engineering perspective, we will probably never be able to turn on the specific genes necessary to "grow an arm" unless it is attached to a fetus and this presents enormous ethical issues related to farming of human organs and structures. Perhaps the most daunting problem facing the transplantation of a tissue engineered or transplanted arm is that of re-innervation of the structure. Since the sensory and motor nerve cells of the arm are located outside of the structure, re-innervation requires those nerves to regenerate over relatively large distances to repopulate the nervous system of the arm. This is something with which we have had little success. We can grow repair parts, but "growing an arm" presents too many insurmountable problems. The best we could possibly do with tissue engineering or genetic engineering would be the equivalent of a fetal arm and the technical problems, costs, and ethical hurdles are enormous. A more likely solution is a functional, permanent, neuroelectronically-controlled prosthesis. These are nearly a reality today.

Ricci JL

2013-11-01

346

Simple model of the arms race  

Energy Technology Data Exchange (ETDEWEB)

A simple model of a two-party arms race is developed based on the principle that the race will continue so long as either side can unleash an effective first strike against the other side. The model is used to examine how secrecy, the ABM, MIRV-ing, and an MX system affect the arms race.

Zane, L.I.

1982-02-01

347

Composites comprising biologically-synthesized nanomaterials  

Energy Technology Data Exchange (ETDEWEB)

The present disclosure describes composite materials containing a polymer material and a nanoscale material dispersed in the polymer material. The nanoscale materials may be biologically synthesized, such as tellurium nanorods synthesized by Bacillus selenitireducens. Composite materials of the present disclosure may have optical limiting properties and find use in optical limiting devices.

Curran, Seamus; Dias, Sampath; Blau, Werner; Wang, Jun; Oremland, Ronald S; Baesman, Shaun

2013-04-30

348

Arms control and disarmament agency  

Energy Technology Data Exchange (ETDEWEB)

In March 1989, the State Department's Inspector General issued a report characterizing the U.S. Arms Control and Disarmament Agency's (ACDA) operations and activities - including its personnel practices - as skewed and lacking organization. Limited development and training programs for career ACDA employees as well as equal employment opportunity problems were noted. In August 1989, OPM recommended that ACDA develop a new structure and career path for its clerical and technical staff. GAO found that top management at ACDA has not taken adequate action to address the personnel management problems identified in these 1989 reports. GAO believes that establishment of more systematic career development, training, and affirmative action programs would demonstrate to career employees at ACDA that management is actively committed to improving personnel practices. This should improve employee morale and enhance work productivity.

1990-10-01

349

Near Infrared Observations of the Local Arm  

CERN Multimedia

Observations of the Local Arm have been carried out in the near-infrared with the 1.5 m ``Carlos Sánchez'' telescope in Tenerife. A model of the disc with adjustable parameters fitted to reproduce the DIRBE-COBE survey, has been subtracted from the observational data in order to obtain a clean map of the Local Arm, uncontaminated by other components of the disc. The arm is more than 70 pc over the plane and is wider than 200 pc. At a latitude of about $80^\\circ$ the deviation of the arm from the the galactic plane is so large that was only partially observed with our observational window of $\\triangle b = \\pm 6^\\circ$. The elevation over the plane vanishes and the width decreases as the Arm comes closer to the Sun.

Porcel, C; Jiménez-Vicente, J; Battaner, E

1998-01-01

350

Synthesis and characterization of thermally stable aromatic polyamides and poly(1,3,4-oxadiazole-amide)s nanoparticles containing pendant substituted bezamides.  

UK PubMed Central (United Kingdom)

BACKGROUND: The introduction of pendent bulky groups along the polymer backbone results in a less ordered polymer matrix and increases the solubility characteristics without affecting thermal properties. The inclusion of chromogenic chemical moieties in the chains can give rise to the luminescent converter material which permits the preparation of materials with potential applications. Aromatic polymers containing heterocyclic rings in the main chain are known for their high thermal resistance, good hydrolytic stability, low dielectric and tough mechanical properties. There is currently much research directed towards the discovery of new blue light-emitting polymers, with characteristics of high efficiency and high reliability. Herein, we describe the preparation of aromatic polyamides and poly (1,3,4-oxadiazole-amide)s nanoparticles with pendant structures comprised of m- and p-acetoxybenzamide groups, where the acetoxybenzamide groups act as signaling units due to their fluorescent and chromogenic characteristics. RESULTS: Aromatic polyamides and poly(1,3,4-oxadiazole-amide)s nanoparticles with pendant structures comprised of m- and p-acetoxybenzamide groups were successfully prepared and characterized using different analytical methods. Most polyamides were obtained as well-separated spherical nanoparticles while aramide containing pyridine produced aggregated particles attributed to the molecular self assembly via H-bond directed organization of molecular precursors. The thermal behavior of all polymers exhibited two major thermal decompositions due to the subsequent breakage of the acetoxy group in the lateral chain and cleavage of the main amide bonds. Photoluminescence studies revealed that the blue emissions for the polyamide derived from benzidine were blue-shifted (shifted to a lower wavelength) compared to that of polyamides containing flexible linkages. CONCLUSIONS: We report the synthesis of aromatic polyamides and poly(1,3,4-oxadiazole-amide)s nanoparticles with pendant structures comprised of m- and p-acetoxybenzamide groups. The thermal behavior of all polymers exhibited two major decompositions due to breakage of the acetoxy group in the lateral chain and cleavage of the main amide bonds. Structure- photoluminescence correlation demonstrated an interesting connection between structural modification and optical properties. The blue emissions for the polyamide derived from benzidine, attributed to the highly conjugation system, was blue shifted with the introduction of flexible linkages. The prepared polymers dissolved in warm polar aprotic solvents. Further investigations to obtain films with reasonably good mechanical properties for different applications are in progress.

Hassan HH; Elhusseiny AF; Elkony YM; Mansour el-SM

2013-01-01

351

Effect of axially projected oligothiophene pendants and nitro-functionalized diimine ligands on the lowest excited state in cationic Ir(III) bis-cyclometalates.  

Science.gov (United States)

The novel terthiophene (3T) oligomer 6 and a series of cationic Ir(III) bis-cyclometalates [Ir(C^N)(2)(N^N)]PF(6) 9-12 were prepared. The synthesis, characterization, electrochemical, and photophysical properties are reported. The cyclometalating ligands (C^N) are 2-phenylpyridinato (ppy) or the 3T oligomer (3T-ppy), asymmetrically capped in the 5 and 5" positions with the ppy and mesityl groups. The diimine ligands (N^N) are 2,2'-bipyridine (bpy) or 4-NO(2)-bipyridine (4-NO(2)-bpy). Hybrid metal-organic complexes 11 and 12 bear 3T-pendants ligated through the ppy cap, 10 and 12 contain NO(2) functionalized diimines, whereas 9 contains neither. Structural characterization of 10 by single crystal X-ray diffraction confirms the presence of the NO(2) substituent and pseudo-octahedral coordination geometry about the Ir(III) ion. Cyclic voltammetry highlights the large electron withdrawing effect of the NO(2) substituent, providing an 850 mV shift toward lower potentials for the first diimine centered reduction of 10 and 12. Strong overlap of the intense ? ? ?* absorptions of the 3T-pendants with Ir(III) charge transfer bands is evident in complexes of 11 and 12, precluding the possibility for selective excitation of either chromophore. Photoexcitation (?(ex) = 400 nm) of the series affords strong luminescence from the 3T oligomer 6 and the unsubstituted 9, with ?(em) = 0.11. In stark contrast the NO(2) and 3T functionalized complexes 10-12 display near total quenching of luminescence. Computations of the ground and excited state electronic structure using density functional theory (DFT) and time-dependent DFT (TD-DFT) indicate that both the NO(2) and 3T substituents play an important role in excited state deactivation of complexes 10-12. A substantial electronic contribution of the NO(2) substituent results in stabilization of the diimine based molecular orbital (MO) and offers an efficient nonradiative decay pathway for the excited state. Spin-orbit coupling effects of the Ir(III) ion lead to efficient population of the low lying, nonluminescent, triplet states centered on the 3T-pendants. PMID:22515216

Schwartz, Kyle R; Chitta, Raghu; Bohnsack, Jon N; Ceckanowicz, Darren J; Miró, Pere; Cramer, Christopher J; Mann, Kent R

2012-04-19

352

Effect of axially projected oligothiophene pendants and nitro-functionalized diimine ligands on the lowest excited state in cationic Ir(III) bis-cyclometalates.  

UK PubMed Central (United Kingdom)

The novel terthiophene (3T) oligomer 6 and a series of cationic Ir(III) bis-cyclometalates [Ir(C^N)(2)(N^N)]PF(6) 9-12 were prepared. The synthesis, characterization, electrochemical, and photophysical properties are reported. The cyclometalating ligands (C^N) are 2-phenylpyridinato (ppy) or the 3T oligomer (3T-ppy), asymmetrically capped in the 5 and 5" positions with the ppy and mesityl groups. The diimine ligands (N^N) are 2,2'-bipyridine (bpy) or 4-NO(2)-bipyridine (4-NO(2)-bpy). Hybrid metal-organic complexes 11 and 12 bear 3T-pendants ligated through the ppy cap, 10 and 12 contain NO(2) functionalized diimines, whereas 9 contains neither. Structural characterization of 10 by single crystal X-ray diffraction confirms the presence of the NO(2) substituent and pseudo-octahedral coordination geometry about the Ir(III) ion. Cyclic voltammetry highlights the large electron withdrawing effect of the NO(2) substituent, providing an 850 mV shift toward lower potentials for the first diimine centered reduction of 10 and 12. Strong overlap of the intense ? ? ?* absorptions of the 3T-pendants with Ir(III) charge transfer bands is evident in complexes of 11 and 12, precluding the possibility for selective excitation of either chromophore. Photoexcitation (?(ex) = 400 nm) of the series affords strong luminescence from the 3T oligomer 6 and the unsubstituted 9, with ?(em) = 0.11. In stark contrast the NO(2) and 3T functionalized complexes 10-12 display near total quenching of luminescence. Computations of the ground and excited state electronic structure using density functional theory (DFT) and time-dependent DFT (TD-DFT) indicate that both the NO(2) and 3T substituents play an important role in excited state deactivation of complexes 10-12. A substantial electronic contribution of the NO(2) substituent results in stabilization of the diimine based molecular orbital (MO) and offers an efficient nonradiative decay pathway for the excited state. Spin-orbit coupling effects of the Ir(III) ion lead to efficient population of the low lying, nonluminescent, triplet states centered on the 3T-pendants.

Schwartz KR; Chitta R; Bohnsack JN; Ceckanowicz DJ; Miró P; Cramer CJ; Mann KR

2012-05-01

353

Modeling Joint Synergies to Synthesize Realistic Movements  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents a new method to generate arm gestures which reproduces the dynamical properties of human movements. We describe a model of synergy, de?ned as a coordinative structure respon- sible for the ?exible organization of joints over time when performing a movement. We propose a generic m...

Aubry, Matthieu; De Loor, Pierre; Gibet, Sylvie

354

Preparation of functional water-soluble low-cytotoxic poly(methacrylate)s with pendant cationic L-lysines for efficient gene delivery.  

UK PubMed Central (United Kingdom)

In this work, we present the preparation of water-soluble poly(methacrylate)s with pendant cationic L-lysines PHMLs(6-30?K). Plasmid DNA binding affinity as well as particle sizes and zeta potentials of the polyplexes were examined for these PHML vectors, and their cytotoxicities were assayed with HeLa cells by CCK-8 and lactate dehydrogenase kits. Gene transfection efficacy and intracellular uptake of the polyplexes by the PHML vectors were also studied with HeLa cells. As a result, it was revealed that the low cytotoxic PHMLs tended to exhibit gene transfection efficiencies significantly higher than those of the linear structural PLL (15-30?K) control, in particular the molecular weight of a PHML vector remarkably influenced its pDNA binding affinity, transfection efficacy and intracellular uptake of the polyplexes.

Sun J; Luo T; Sheng R; Li H; Chen S; Hu F; Cao A

2013-01-01

355

The evolution of neuroArm.  

UK PubMed Central (United Kingdom)

Intraoperative imaging disrupts the rhythm of surgery despite providing an excellent opportunity for surgical monitoring and assessment. To allow surgery within real-time images, neuroArm, a teleoperated surgical robotic system, was conceptualized. The objective was to design and manufacture a magnetic resonance-compatible robot with a human-machine interface that could reproduce some of the sight, sound, and touch of surgery at a remote workstation. University of Calgary researchers worked with MacDonald, Dettwiler and Associates engineers to produce a requirements document, preliminary design review, and critical design review, followed by the manufacture, preclinical testing, and clinical integration of neuroArm. During the preliminary design review, the scope of the neuroArm project changed to performing microsurgery outside the magnet and stereotaxy inside the bore. neuroArm was successfully manufactured and installed in an intraoperative magnetic resonance imaging operating room. neuroArm was clinically integrated into 35 cases in a graded fashion. As a result of this experience, neuroArm II is in development, and advances in technology will allow microsurgery within the bore of the magnet. neuroArm represents a successful interdisciplinary collaboration. It has positive implications for the future of robotic technology in neurosurgery in that the precision and accuracy of robots will continue to augment human capability.

Sutherland GR; Wolfsberger S; Lama S; Zarei-nia K

2013-01-01

356

Design Lower Arm Using Optimum Approach  

Directory of Open Access Journals (Sweden)

Full Text Available In the automotive industry, the riding comfort and handling qualities of an automobile are greatly affected by the suspension system. This paper presents the robust design of vehicle suspension arm using stochastic design improvement (SDI) technique based on Monte Carlo simulation. The main goal of this study is to determine the optimum design for the suspension arm. The structural model of the suspension arm was utilizing the Solid works and aluminum alloys (AA7075-T6) are selected as a suspension arm materials. The linear static stress distribution is investigated using the commercial Finite element analysis package, and dynamic analysis was performed using NASTRAN software. SDI has been performed to the design. A target output behavior is selected from the output variables available in the analysis. The result shows that the lower arm design has a higher capability to stand higher pressure as 9.18 MPa with the stress acted on lower arm is 41 MPa. The new parameter of material can be chose as optimum result for the lower suspension arm.

Adel Mahmoud Bash

2011-01-01

357

The dynamics of stars around spiral arms  

CERN Document Server

Spiral density wave theory attempts to describe the spiral pattern in spiral galaxies in terms of a long-lived wave structure with a constant pattern speed in order to avoid the winding dilemma. The pattern is consequently a rigidly rotating, long-lived feature. We run N-body simulations of a giant disc galaxy consisting of a pure stellar disc and a static dark matter halo, and find that the spiral arms are transient features whose pattern speeds decrease with radius, in such a way that the pattern speed is almost equal to the rotation curve of the galaxy. We trace particle motion around the spiral arms. We show that particles from behind and in front of the spiral arm are drawn towards and join the arm. Particles move along the arm in the radial direction and we find a clear trend that they migrate toward the outer (inner) radii on the trailing (leading) side of the arm. Our simulations demonstrate that because the spiral arm feature is co-rotating, the particles continue to be accelerated (decelerated) by t...

Grand, Robert J J; Cropper, Mark

2011-01-01

358

The relationship between height and arm span, mid-upper arm and waist circumferences in children.  

UK PubMed Central (United Kingdom)

BACKGROUND: Height is a significant parameter in assessment of growth, development, and nutritional status. OBJECTIVE: The aim of this study was to assess the relationship between height and arm span, mid-upper arm and waist circumferences in Turkish children. SUBJECTS AND METHODS: Height, arm span, mid-upper arm and waist circumferences were measured in 1145 boys and 1372 girls aged 7-14 years old from metropolitan Ankara schools in Turkey. RESULTS: Among the children aged between 7 and 14 years old the arm span was determined to be shorter than height. The correlation coefficient between height and arm span of children aged 7-10 years old was 0.92 for boys and 0.90 for girls, and was 0.89 for boys and 0.85 for girls aged 11-14 years old. The correlation between height and arm span was high in both genders at the age group of 7-10 years old. Moreover, significant correlations were found between the height, the mid-upper arm and waist circumferences. CONCLUSIONS: Arm span was found to be strongly correlated with height. Although mid-upper arm and waist circumferences were moderately correlated, waist circumference was not detected as a predictor for height in girls and boys.

Yabanci N; Kiliç S; Sim?ek I

2010-01-01

359

Universal Controller Design Using Arm Controller  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, different control strategies are discussed and design of universal (process) controller on ARM embedded platform is proposed. The same controller support feedback, cascade, ratio and feed forward control strategy. The LPC2148 kit (ARM7 controller) is used for the application which has many features which are also discussed in the paper.MODBUS RTU protocol is used for communication.GUI is developed in Wonderware In touch (SCADA) software. Keil µvision 4 IDE is used for programming ARM controller

Mohsin A. Bandi, Mr. Naimesh B. Mehta

2012-01-01

360

Arms control, nonproliferation, and US national security  

International Nuclear Information System (INIS)

The continuation of the arms race and the failure of arms control and disarmament negotiations lend support to the belief that US and Soviet power, prestige, and security depend upon nuclear weapons. Therefore, the argument goes, the non-nuclear-weapon states (particularly those that are not allied with nuclear-weapon states and do not share their nuclear shield) may conclude that they would be well served by possession of these weapons. In this sense, the failure of nuclear arms reductions could create incentives for further proliferation

1985-01-01

 
 
 
 
361

The Milky Way Spiral Arm Pattern  

CERN Multimedia

A complete map of the 3D distribution of molecular (CO) gas was constructed using a realistic dynamical model of the gas flow in the barred potential of the Milky Way. The map shows two prominent spiral arms starting at the bar ends connecting smoothly to the 4-armed spiral pattern observed in the atomic hydrogen gas in the outer Galaxy. Unlike previous attempts, our new map uncovers the gas distribution in the bar region of the Galaxy and the far side of the disk. For the first time, we can follow spiral arms in gas as they pass behind the galactic centre.

Englmaier, Peter; Bissantz, Nicolai

2008-01-01

362

Method of making a rocker arm  

Energy Technology Data Exchange (ETDEWEB)

A method of producing a rocker arm is described, comprising: forming a rocker arm having a valve contacting portion, a cam contacting portion and a pivot portion for contact with a pivot of a lash adjuster and entirely made of ceramics; processing the rocker arm by barrel finishing; and; grinding the pivot portion by using the valve contacting portion and the cam contacting portion as datum surfaces and thereby locating the pivot portion in position relative to the valve contacting portion and the cam contacting portion.

Taniguchi, M.; Kawamura, M.; Ishida, N.; Ito, M.

1989-06-27

363

Olecranon fracture sustained in arm wrestling.  

UK PubMed Central (United Kingdom)

This case report describes an arm-wrestling injury in which a violent triceps contraction was determined to have caused an olecranon fracture. Such a fracture has not been reported in arm wrestling; more typical are fractures of the humeral shaft or medial epicondyle. The authors suggest awareness of this potential and recommend appropriate radiographic studies for injuries involving intense muscle contraction. The patient was treated conservatively. After rehabilitation, he was able to return to his job, which involved lifting, but did not resume arm wrestling.

Pasquina PF; O'Connor FG

1999-04-01

364

Olecranon fracture sustained in arm wrestling.  

Science.gov (United States)

This case report describes an arm-wrestling injury in which a violent triceps contraction was determined to have caused an olecranon fracture. Such a fracture has not been reported in arm wrestling; more typical are fractures of the humeral shaft or medial epicondyle. The authors suggest awareness of this potential and recommend appropriate radiographic studies for injuries involving intense muscle contraction. The patient was treated conservatively. After rehabilitation, he was able to return to his job, which involved lifting, but did not resume arm wrestling. PMID:20086713

Pasquina, P F; O'Connor, F G

1999-04-01

365

Science, technology and the nuclear arms race  

Energy Technology Data Exchange (ETDEWEB)

This book presents a survey of the nuclear arms race from a technological point of view. It provides information for the layman on this topic and is designed for undergraduate courses in political science, history,international studies, as well as physics courses on the subject. The work explores the motivation behind the development of various nuclear arms technologies and their deployment and examines the effects these technologies have on military, political and social strategies. The nature of deterrence and alternatives to it, arms control, and disarmament are discussed.

Schroeer, D.

1984-01-01

366

ARM Climate Research Facility Annual Report 2005  

Energy Technology Data Exchange (ETDEWEB)

Through the ARM Program, the DOE funded the development of several highly instrumented ground stations for studying cloud formation processes and their influence on radiative transfer, and for measuring other parameters that determine the radiative properties of the atmosphere. This scientific infrastructure, and resultant data archive, is a valuable national and international asset for advancing scientific knowledge of Earth systems. In fiscal year (FY) 2003, the DOE designated ARM sites as a national scientific user facility: the ARM Climate Research (ACRF). The ACRF has enormous potential to contribute to a wide range interdisciplinary science in areas such as meteorology, atmospheric aerosols, hydrology, biogeochemical cycling, and satellite validation, to name only a few.

J. Voyles

2005-12-31

367

Technology and the nuclear arms race  

Energy Technology Data Exchange (ETDEWEB)

Many writers have examined the causes of the nuclear arms race. Some have looked at global political factors, in particular the growing mistrust and animosity between the superpowers. Others have looked at the economics of arms production, including its profitability and its role in propping up a failing economy. This article examines the roots of the arms race in modern technology and in the particular human values that underlie this technology. It argues that the task of nuclear disarmament involves a transformation of our system of technology to one expressing very different values. The living of these values and the effort to change our technology are vital to the peace movement. 9 references.

Lacey, G.

1983-03-01

368

Total syntheses of (±)-?-lycorane and (±)-1-deoxylycorine.  

UK PubMed Central (United Kingdom)

New synthetic routes to (±)-?-lycorane and (±)-1-deoxylycorine were exploited. The endo-cycloadduct of 3,5-dibromo-2-pyrone with styrene-type dienophile provided the pivotal intermediate for the syntheses of the titled natural products.

Jung YG; Lee SC; Cho HK; Darvatkar NB; Song JY; Cho CG

2013-01-01

369

Syntheses and Properties of Some Organosilane Polymers.  

Science.gov (United States)

Some organosilane polymers with high molecular weights have been synthesized by cocondensation of organosilicon dihalide monomers with sodium metal in toluene. These polymers are both soluble in common solvents and meltable at lower temperatures, and can ...

X. Zhang R. West

1984-01-01

370

Syntheses and Functional Properties of Phthalocyanines  

Directory of Open Access Journals (Sweden)

Full Text Available Metal phthalocyanine tetrasulfonic acids, metal phthalocyanine octacarboxylic acids, metal octakis(hexyloxymethyl)phthalocyanines, and metal anthraquinocyanines have been synthesized. Then, zinc bis(1,4-didecylbenzo)-bis(3,4-pyrido)porphyrazines, the cyclotetramerization products of a 1:1 mixture of 3,6-didecylphthalonitrile and 3,4-dicyanopyridine, were synthesized. Futher, subphthalocyanine and its derivatives, with substituents such as thiobutyl and thiophenyl moieties were synthesized. Electrochemical measurements were performed on the abovementioned phthalocyanine derivatives and analogues in order to examine their electron transfer abilities and electrochemical reaction mechanisms in an organic solvent. Moreover, 1,4,8,11,15,18,22,25-octakis(thiophenylmethyl) phthalocyanes were synthesized. The Q-bands of the latter compounds appeared in the near-infrared region. Furthermore, non-colored transparent films in the visible region can be produced.

Keiichi Sakamoto; Eiko Ohno-Okumura

2009-01-01

371

Syntheses of Novel Nitrogen and Phosphorus Heterocycles.  

Science.gov (United States)

1-Dichlorophospha-3,5-perfluoro-n-heptyl (or perfluoroalkylether)-2,4,6-triazines were synthesized by interaction of imidoylamidines with phosphorus pentachloride. In a parallel approach, 1,3-bis(phenylchlorophospha)-5-perfluoroalkyl (or perfluoroalkyleth...

K. L. Paciorek J. H. Nakahara D. H. Harris M. E. Smythe R. H. Kratzer

1985-01-01

372

Two syntheses of FF-MAS.  

UK PubMed Central (United Kingdom)

[reaction: see text] Follicular fluid-meiosis activating sterol (FF-MAS) has been shown to be an efficient inducer of meiotic maturation. It can potentially be used for improvements of in vitro fertilization techniques. Two short synthesis of FF-MAS are presented in this article. Both syntheses are based on microbiological degradations of sterol side chains. FF-MAS can be synthesized in nine steps from commercially available starting materials by both routes.

Blume T; Guttzeit M; Kuhnke J; Zorn L

2003-05-01

373

SYNTHESIZED CAPITAL AND MODERNIZATION OF SOCIETY  

Directory of Open Access Journals (Sweden)

Full Text Available At present in Ukraine, the processes of integration and globalization are deepening, the impact of economic factors in all spheres of life has increased, and innovative investment model of development is being formed in the state. The research of issues related to the synthesized capital in the context of modernization complies with modern challenges of national scientific thought, taking into account the fact that capitalization of synthesized capital can increase its overall value and can be regarded as a means of society modernization, reflecting the importance and urgency of this work.The objective of the article is to establish the scientific and theoretical principles of synthesized capitalization as a means of society modernization.The continuous development of a country, region, an enterprise within the scope of modernization is feasible under conditions of capitalization, resulting in the processes associated with transfer of synthesized capital, increasing the relative value added. We believe that capitalization of synthesized capital should be seen as the means of modernization of society and should lead to the following:· accumulation of synthesized (human, intellectual and social) capital of the country, followed by its distribution at the national level (it is about creating national and regional integrated structures, TNK and clusters which may include universities);· creation of conditions for the transformation of synthesized capital in to geo-economic capital of the country, which should ensure both efficient creation of innovative model of an enterprise development and socio-economic development of the country.The authors’ calculations along with updating capitalization of synthesized capital allows to specify the strategic directions of the development of the country towards sustainability of its socio-economic configuration of modernization.

N. Gavkalova; M. Barka Zine

2012-01-01

374

Synthesis, conformational and spectroscopic characterization of monomeric styrene derivatives having pendant p-substituted benzylic ether groups.  

Science.gov (United States)

Three derivatives of styrene monomer, 4-chlorophenyl-4-vinylbenzyl ether (I), 4-methoxyphenyl-4-vinylbenzyl ether (II) and 4-ethylphenyl-4-vinylbenzyl ether (III) were synthesized. The synthesized two novel compounds (I and III) and one with undefined structural features were identified by experimental spectroscopic techniques and density functional approach. The optimized geometrical structure, vibrational and electronic transitions along with chemical shifts of those compounds were presented in this study. The vibrational spectra of investigated compounds were recorded in solid state with FT-IR spectrometry in the range of 4000-400 cm(-1). The computational vibrational wavenumbers and also ground state equilibrium conformations were carried out by using density functional method with 6-311++G(d,p) basis set. Assignments of the fundamental vibrational modes were examined on the basis of the measured data and total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanical (SQM) method. Isotropic chemical shift of hydrogen and carbon nuclei were investigated via observed (1)H and (13)C NMR spectra in deuterated DMSO solution and predicted data applied with gauge-invariant atomic orbitals (GIAOs) method. The UV absorption spectra of monomers were observed in the range of 200-800 nm in ethanol, and time dependent DFT method was used to obtain the electronic properties. A detailed description of spectroscopic behaviors of compound was given based on the comparison of experimental measurements and theoretical computations. PMID:23608133

Cinar, Mehmet; Ozcan, Levent; Karabacak, Mehmet; Erol, Ibrahim

2013-03-28

375

Synthesis, conformational and spectroscopic characterization of monomeric styrene derivatives having pendant p-substituted benzylic ether groups.  

UK PubMed Central (United Kingdom)

Three derivatives of styrene monomer, 4-chlorophenyl-4-vinylbenzyl ether (I), 4-methoxyphenyl-4-vinylbenzyl ether (II) and 4-ethylphenyl-4-vinylbenzyl ether (III) were synthesized. The synthesized two novel compounds (I and III) and one with undefined structural features were identified by experimental spectroscopic techniques and density functional approach. The optimized geometrical structure, vibrational and electronic transitions along with chemical shifts of those compounds were presented in this study. The vibrational spectra of investigated compounds were recorded in solid state with FT-IR spectrometry in the range of 4000-400 cm(-1). The computational vibrational wavenumbers and also ground state equilibrium conformations were carried out by using density functional method with 6-311++G(d,p) basis set. Assignments of the fundamental vibrational modes were examined on the basis of the measured data and total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanical (SQM) method. Isotropic chemical shift of hydrogen and carbon nuclei were investigated via observed (1)H and (13)C NMR spectra in deuterated DMSO solution and predicted data applied with gauge-invariant atomic orbitals (GIAOs) method. The UV absorption spectra of monomers were observed in the range of 200-800 nm in ethanol, and time dependent DFT method was used to obtain the electronic properties. A detailed description of spectroscopic behaviors of compound was given based on the comparison of experimental measurements and theoretical computations.

Cinar M; Ozcan L; Karabacak M; Erol I

2013-07-01

376

Identification of robot arm’s joints’ time-varying stiffness under loads  

Directory of Open Access Journals (Sweden)

Full Text Available This paper is concerned with the identification problem of two degree of freedom robot arm’s joints’ time-varying stiffness under time-varying torque loads. The industrial robot arms can be simplified into series hinged linkage mechanism. The unrestraint dynamic equation of two degrees of freedom robot arm can be obtained by using analytical mechanics method. The model which was established in Pro/E had been imported into ADAMS for simulation. And the simulation consisted of free vibration and forced vibration. Then by choosing limited memory least square method and using the post-processing measured variables, time-varying stiffness could have been identified. Finally, the calculative stiffness was compared to the “real” stiffness which was simulated in ADAMS. The whole process shows that the robot arm’s dynamic model and the method of identification are both effective.

Rui Xu; Qiang Chen; Guolai Yang

2012-01-01

377

Worldwide report: Arms control, [October 18, 1985  

Energy Technology Data Exchange (ETDEWEB)

Partial contents of this report are: SDI and Space; Arms SALT/START Issues; Intermediate-Range Nuclear Forces; Mutual and Balanced Force Reductions; Chemical/Biological Weapons; Nuclear-Free-Zone Proposals; and Prevention of Nuclear War.

NONE

1985-10-18

378

JOINT SMALL-ARMS RANGE REMEDIATION  

Science.gov (United States)

This Environmental Security Technology Certification Program (ESTCP) demonstration conducted by the Naval Facilities Engineering Service Center (NFESC) and the Army Environmental Center (AEC) removed lead and other heavy metals from small-arms range soils by a combination of phys...

379

Rosa's strong arm approach to dose reduction  

International Nuclear Information System (INIS)

To minimize personnel exposure during maintenance, and indeed to make some types of maintenance possible at all, Westinghouse has developed a robotic arm system called Rosa. It is specifically designed for high radiation environments, including underwater repair. (author).

1985-01-01

380

JPRS report: Arms control, [July 19, 1989  

Energy Technology Data Exchange (ETDEWEB)

This document contains articles on arms control. Some topics discussed are international affairs, Warsaw Pact meetings, chemical weapons and export policies, political science, nuclear disarmament, NATO, troop withdrawals, military operations, nuclear submarines and nuclear deterrence.

NONE

1989-07-19

 
 
 
 
381

JPRS report: Arms control, [April 26, 1989  

Energy Technology Data Exchange (ETDEWEB)

This document contains articles on arms control. Some topics discussed in this document are toxic bombs, disarmament, defense issues, joint military exercises, troop withdrawal, international relations, missile launches, nuclear weapons, NATO, nuclear deployments, defense systems, and weapons modernization.

NONE

1989-04-26

382

78 FR 30731 - Armed Forces Day, 2013  

Science.gov (United States)

...these heroes have sacrificed to sustain that powerful promise that we hold so dear-- life, liberty, and the pursuit of happiness. And on Armed Forces Day, we honor those who serve bravely and sacrifice selflessly in our name. Our Soldiers,...

2013-05-22

383

Emerging Technology Systems and Arms Control.  

Science.gov (United States)

The Strategic Arms Reductions Treaty (START) and the Conventional Forces in Europe (CFE) agreements call for unprecedented cuts in strategic nuclear and conventional forces. But in contrast to earlier attempts to restrict technology development in previou...

R. Lempert I. Y. Chang K. McCallum

1991-01-01

384

MiniSAR composite gimbal arm development.  

Energy Technology Data Exchange (ETDEWEB)

An exploratory effort in the application of carbon epoxy composite structural materials to a multi-axis gimbal arm design is described. An existing design in aluminum was used as a baseline for a functionally equivalent redesigned outer gimbal arm using a carbon epoxy composite material. The existing arm was analyzed using finite element techniques to characterize performance in terms of strength, stiffness, and weight. A new design was virtually prototyped. using the same tools to produce a design with similar stiffness and strength, but reduced overall weight, than the original arm. The new design was prototyped using Rapid Prototyping technology, which was subsequently used to produce molds for fabricating the carbon epoxy composite parts. The design tools, process, and results are discussed.

Klarer, Paul Richard; Winscott, Mark (Orion International, Albuquerque, NM)

2005-01-01

385

An arms control phoenix: Building transparency through an arms trade register  

Energy Technology Data Exchange (ETDEWEB)

The idea of an arms trade register was first discussed at the League of Nations. The League of Nations spent considerable time addressing ways to supervise and control the international trade in arms. The League's work in this regard was carried out at various conferences. In conjunction with the political negotiations, the League Secretariat compiled statistical information on the international trade in arms, in anticipation of a political decision to implement such a scheme. In the post-1945 era, the idea of a register was dormant for a number of years as attention was focused on nuclear arms rather than conventional arms. Recently, it has again come to the forefront. Using the frameworks of arms control theory and regime theory, the concept of the idea of an arms trade register as a viable way to promote transparency in the international arms trade. A study has just been completed for the Secretary-General of the United Nations recommending the immediate implementation of a register. However, this will not necessarily ensure its successful implementation. While the nature of the arms trade has changed over the past century in terms of its patterns, scope and sophistication, little has changed in the attitudes towards dealing with it. In fact, the arguments articulated at the United Nations have demonstrated little new thinking, and mirror those made at the League of Nations. As a result, efforts to implement an arms trade register in the late twentieth century confront many of the same obstacles, but with the added twist that, due to changes in the nature of the arms trade, the register may no longer be the appropriate instrument of supervision. In the wake of the Gulf War, the advocacy of an arms trade register by the United Kingdom, Japan, and Canada, amongst others, offers new hope to its supporters, but the implementation of the proposal will still required the resolution of the problems that have traditionally confronted the concept.

MacDonald, M.K.

1991-01-01

386

Magnetic field in Perseus spiral arm  

International Nuclear Information System (INIS)

The rotation measures data for extragalactic radio sources are used to estimate the value and direction of large-scale galactic magnetic field in the Perseus spiral arm. The field of a value of |B| ? 3.2 ?G lies in the galactic plane. It is directed along ? 280 deg in the opposite direction compared to the magnetic field in the local Orion arm. A variance of the field is of the other of ?B/B ? 1.4.

1988-01-01

387

Arm exponents in high dimensional percolation  

CERN Document Server

We study the probability that the origin is connected to the sphere of radius r (an arm event) in critical percolation in high dimensions, namely when the dimension d is large enough or when d>6 and the lattice is sufficiently spread out. We prove that this probability decays like 1/r^2. Furthermore, we show that the probability of having k disjoint arms to distance r emanating from the vicinity of the origin is 1/r^2k.

Kozma, Gady

2009-01-01

388

Construction of the PHENIX south muon arm  

International Nuclear Information System (INIS)

Installation of the south PHENIX muon arm was completed in January 2001. The role of the muon arm is to track and identify muons, providing good rejection of pions and kaons. In order to accomplish this, we employ a radial field magnetic spectrometer with precision tracking (muon tracker) followed by a stack of absorber/low resolution tracking layers (muon identifier). We report the design, construction and performance of the muon tracker and the muon identifier.

2002-04-02

389

Can NATO agree on arms control  

Energy Technology Data Exchange (ETDEWEB)

This article addresses the prospects for military cuts between NATO and the Warsaw Pact. The Vienna talks on Conventional Armed Forces in Europe (CFE) is discussed. The author focuses on armament issues within NATO, including the magnitude of western armed forces reductions, the imposition of ceilings on troops and armaments once cuts have been made, how to verify reductions, how to subdivide the territory on which cuts will take place, and how to control weapons production.

Dean, J. (Union of Concerned Scientists (US))

1989-10-01

390

Regulation of flexible arms under gravity  

Energy Technology Data Exchange (ETDEWEB)

A simple controller is presented for the regulation problem of robot arms with flexible links under gravity. It consists of a joint PD feedback plus a constant feedforward. Global asymptotic stability of the reference equilibrium state is shown under a structural assumption about link elasticity and a mild condition on the proportional gain. The result holds also in the absence of internal damping of the flexible arm. A numerical case study is presented.

De Luca, A. [Univ. di Roma, Rome (Italy). Dipt. di Informatica e Sistemistica; Siciliano, B. [Univ. di Napoli Federico, Napoli (Italy). Dipt. di Informatica e Sistemistica

1993-08-01

391

Arms trade as a global international problem  

Directory of Open Access Journals (Sweden)

Full Text Available The aim of this paper is to highlight the great social danger resulting from uncontrolled trade in arms and military equipment. A large number of terrorist attacks in the world show that uncontrolled arms trade is a growing problem for international security. In order to provide the same protection, the problem of uncontrolled arms and military equipment, which is the major international business, should be viewed from several aspects. To this end, after defining weapons, their production and trade, the authors have presented one of the ways the leading companies in the military-industrial complex provide themselves a market for sale of arms and military equipment, thus creating the conditions that contribute to expanding of their military companies. As the world’s largest exporters of arms and military equipment the United States, Russia and China give a short historical account of their arms trafficking. Then, considering the fact that the amount of weapons would unlikely diminish, the authors have pointed out that states should find a way to control the movement of weapons in the world preventing terrorist to take hold of them.

Spalevi? Žaklina; Bjelajac Željko; Dimitrijevi? Duško

2013-01-01

392

Arm & Interarm Star Formation in Spiral Galaxies  

CERN Multimedia

We investigate the relationship between spiral arms and star formation in the grand-design spirals NGC 5194 and NGC 628 and in the flocculent spiral NGC 6946. Filtered maps of near-IR (3.6 micron) emission allow us to identify "arm regions" that should correspond to regions of stellar mass density enhancements. The two grand-design spirals show a clear two-armed structure, while NGC 6946 is more complex. We examine these arm and interarm regions, looking at maps that trace recent star formation - far-ultraviolet (GALEX NGS) and 24 micron emission (Spitzer, SINGS) - and cold gas - CO (Heracles) and HI (Things). We find the star formation tracers and CO more concentrated in the spiral arms than the stellar 3.6 micron flux. If we define the spiral arms as the 25% highest pixels in the filtered 3.6 micron images, we find that the majority (60%) of star formation tracers occurs in the interarm regions; this result persists qualitatively even when considering the potential impact of finite data resolution and diffu...

Foyle, Kelly; Walter, Fabian; Leroy, Adam

2010-01-01

393

Initial psychometric evaluation of the Arm Activity Measure (ArmA): a measure of activity in the hemiparetic arm.  

UK PubMed Central (United Kingdom)

OBJECTIVE: To evaluate the psychometric properties of the Arm Activity Measure (ArmA), a patient-reported measure of active and passive function in the paretic upper limb. DESIGN: Psychometric evaluation study. SETTING: Two specialist rehabilitation and spasticity management services. METHOD: Patients (n = 92) with upper limb paresis were recruited from two specialist neurorehabilitation centres. Mean age 44.5 (SD 16.7). Diagnostic distribution: stroke 48 (52%); other brain injury 28 (31%); or other neurological condition 16 (17%). Evaluation of convergent and divergent validity; unidimensionality, scaling, reliability (internal consistency and test-retest); responsiveness to change and feasibility of the ArmA were undertaken. RESULTS: Expected convergent and divergent relationships were seen with the Leeds Adult Spasticity Impact Scale and the Disabilities of Arm Shoulder and Hand (DASH) (rho 0.5-0.63). Principal components analysis confirmed that active and passive function formed two separate constructs in each sub-scale. Mokken analysis corroborated the findings of the principal components analysis and demonstrated scaling using the monotone homogeneity model (Item H>0.5 for all items). Cronbach's alpha was 0.85 and 0.96, respectively, for the passive and active function subscales. Item level test-retest agreement ranged from 92-97.5% (quadratic-weighted Kappa 0.71-0.94). In the subgroup treated for spasticity with botulinum toxin (n = 58), the ArmA passive function scale identified a significant difference between responder and non-responder groups (Mann Whitney U = 0.85, p < 0.01). Respondents reported the ArmA to be relevant (77%), easy to use (90%) and timely to complete (83% under 10 minutes). CONCLUSION: The ArmA is a valid and reliable tool feasible for use in the evaluation of upper limb function in the context of treatment for spasticity.

Ashford S; Turner-Stokes L; Siegert R; Slade M

2013-08-01

394

The development of multipurpose fluorination synthesizer  

International Nuclear Information System (INIS)

The purpose of this project is developing the multipurpose fluorination synthesizer, which can produce various fluorination compounds that are used for the PET. The main results are as follows 1. We have intended to design a multipurpose synthesizer that can be used not only for the FDG synthesis, which is the most popular in the F-18 radioisotope labeled radiopharmaceutical, but also for the FLT and FET synthesis. In addition, the developed synthesizer is allowed to connect and control the HPLC system so that we can produce another type of fluorination compound different from the FDG. 2. The program suitable to the multipurpose fluorination synthesizer should manages appropriate sequences separately for each step. In other words, the program should can be modified by user at any time, and the user using the program is allowed to define or modify each step easily through the GUI interface. 3. The yield of the FDG synthesis is about 7% higher than the previous synthesizer and the radiochemical yield of [18F]FLT synthesis is 96% using the network based module We will provide a chance that having a technology transfer to domestic cyclotron manufacturers. The technology transferred domestic cyclotron manufacturers may accomplish a kind of package product by producing the PET radioisotopes and radiopharmaceuticals, and they can increase their marketability

2009-01-01

395

Method for synthesizing 9-fluorenylmethoxycarbonyloxy succinimide ester  

UK PubMed Central (United Kingdom)

The invention relates to a method for synthesizing an amino acid protective agent, in particular to a method for synthesizing 9-fluorenylmethoxycarbonyloxy succinimide ester (abbreviated as Fmoc-ONSu), which comprises the following steps of: a), adding an organic solvent, Fmoc-Cl, N-hydroxysuccimide and a catalyst into a reactor to perform a reaction, wherein the Fmoc-Cl and the N-hydroxysuccimide are reactants, and the solvent is a non-protonic solvent and b) filtering the reaction product in the reactor to obtain solid and residual liquid, and drying the solid to obtain the 9-fluorenylmethoxycarbonyloxy succinimide ester product. The method has the advantages of simple process, safety, convenience, mild condition and high yield. The synthesized Fmoc-ONSu product has a purity of over 98 percent and therefore does not need to be refined.

YEFEI CHEN; YE XIA

396

Dual Arm Work Module Development and Appplications  

Energy Technology Data Exchange (ETDEWEB)

The dual arm work module (DAWM) was developed at Oak Ridge National Laboratory (ORNL) by the Robotics Technology Development Program (RTDP) as a development test bed to study issues related to dual arm manipulation, including platform cotilguration, controls, automation, operations, and tooling. The original platform was based on two Schilling Titan II manipulators mounted to a 5-degree-of- freedom (DOF) base fabricated by RedZone Robotics, Inc. The 5-DOF articulation provided a center torso rotation, linear actuation to change the separation between the arms, and arm base rotation joints to provide "elbows up," elbows down," or "elbows out" orientation. A series of tests were conducted on operations, tooling, and task space scene analysis (TSSA)-driven robotics for overhead transporter- mounted and crane hook-deployed scenarios. A concept was developed for DAWM deployment from a large remote work vehicle, but the project was redirected to support dismantlement of the Chicago Pile #5 (CP-5) reactor at Argonne National Laboratory in fiscal year (FY) 1997. Support of CP-5 required a change in focus of the dual arm technology from that of a development test bed to a system focussed for a specific end user. ORNL teamed with the Idaho National Environmental ,Engineering Laboratory, Sandia National Laboratory, and the Savannah River Technology Center to deliver a crane-deployed derivative of the DAWM, designated the dual arm work platform (DAWP). RTDP staff supported DAWP at CP-5 for one FY; Argonne staff continued operation through to dismantlement of the reactor internals. Lessons learned from this interaction were extensive. Beginning in FY 1999, dual arm development activities are again being pursued in the context of those lessons learned. This paper describes the progression of philosophy of the DAWM from initial test bed to lessons learned through interaction at CP-5 and to the present investigation of telerobotic assist of teleoperation and TSSA- driven robotics.

Noakes, M.W.

1999-04-25

397

Syntheses of biologically active ubiquinone derivatives.  

UK PubMed Central (United Kingdom)

Various 6-alkylubiquinone or 6-(omega-haloalkyl)ubiquinone derivatives were synthesized through a radical coupling reaction between alkanoyl or omega-haloalkanoyl peroxides and ubiquinone 0. The latter was synthesized from 2-methoxy-4-methylphenol via nitration, methylation, reduction, and oxidation by modifications of the reported methods. 6-(omega-Haloalkyl)ubiquinones were converted to 6-(omega-hydroxyalkyl)ubiquinones by a mercuric-assisted solvolysis technique. The 6-(omega-hydroxyalkyl)ubiquinones were then esterified with carboxylic acid anhydrides or carboxylic acid bearing reporting groups, such as a photoaffinity label, N-(4-azido-2-nitrophenyl)-beta-alanine, or a spin-label, 3-carboxy-2,2,5,5-tetramethyl-3-pyrrolinyl-1-oxy. The esterification was catalyzed by dicyclohexylcarbodiimide and pyridine, and the esters were purified by preparative silica gel thin-layer chromatography, developed by 3% ethanol in benzene. The spectral properties and biological functions of the synthesized ubiquinone derivatives were studied. The biological function of the synthesized compounds was followed by the ability to serve as an electron acceptor, donor, or mediator in the isolated mitochondrial electron transfer complexes of succinate-Q reductase, ubiquinol-cytochrome c reductase, and succinate-cytochrome c reductase, respectively. The concentration effect of these ubiquinone derivatives on the electron transfer reaction was compared with that of ubiquinone 10. The study of the inhibitory effect of synthesized arylazidoubiquinone on succinate-cytochrome c reductase after photolysis confirmed the existence of specific Q-binding proteins in this segment of the respiratory chain. The specific interaction between ubiquinone and protein has also gained support from the immobilization of the spin-label of a synthesized spin-labeled ubiquinone derivative.

Yu CA; Yu L

1982-08-01

398

An automated Teflon microfluidic peptide synthesizer.  

UK PubMed Central (United Kingdom)

We present a microfluidic synthesizer made entirely of Teflon material for solid phase peptide synthesis (SPPS). Solvent-resistant perfluoroalkoxy (PFA) was used to construct chip-sized devices featuring multiple tri-layer pneumatic microvalves. Using these devices, model peptides were automatically synthesized and cleaved in situ in a continuous-flow manner. The total coupling and cleavage time was significantly reduced compared to conventional bulk reactors. The synthesis of a decapeptide, for instance, took less than 6 h using our device while it usually takes more than three days using conventional reactors.

Zheng H; Wang W; Li X; Wang Z; Hood L; Lausted C; Hu Z

2013-09-01

399

An automated Teflon microfluidic peptide synthesizer.  

Science.gov (United States)

We present a microfluidic synthesizer made entirely of Teflon material for solid phase peptide synthesis (SPPS). Solvent-resistant perfluoroalkoxy (PFA) was used to construct chip-sized devices featuring multiple tri-layer pneumatic microvalves. Using these devices, model peptides were automatically synthesized and cleaved in situ in a continuous-flow manner. The total coupling and cleavage time was significantly reduced compared to conventional bulk reactors. The synthesis of a decapeptide, for instance, took less than 6 h using our device while it usually takes more than three days using conventional reactors. PMID:23835869

Zheng, Hui; Wang, Weizhi; Li, Xiaojun; Wang, Zihua; Hood, Leroy; Lausted, Christopher; Hu, Zhiyuan

2013-07-08

400

Chemically synthesized graphene for electrochemical biosensing.  

UK PubMed Central (United Kingdom)

We report a new chemical method for synthesis of graphene with good yield. Graphene obtained by this chemical route was subjected to electrochemical characterization using two different redox materials for their suitability in electrochemical biosensing applications. The synthesized graphene was used for the detection of neurotransmitters like dopamine and serotonin. The electrodes exhibited 20% +/- 5% (N = 5) decrease in their signal after forty five days storage in the laboratory atmosphere. High stability of chemically synthesized graphene as electrochemical biosensor is presented in this work.

Mishra M; Alwarappan S; Joshi RK; Mohanty T

2013-06-01

 
 
 
 
401

Continuation method for synthesizing antireflection coatings.  

UK PubMed Central (United Kingdom)

A continuation method for synthesizing antireflection multilayer coatings is presented. It takes into account the family of similar problems constituted by the syntheses of spectrally flat coatings that approximate different transmittance levels in the range 0-1. This method traces a path moving from the transmittance (in air) of the chosen substrate to the full transmittance. Whenever one or more thicknesses become too thin, this path is branched by investigating the existence of other local minima, so several optimal designs characterized by different numbers of layers are obtained. Some examples show the capabilities of the proposed synthesis.

Rastello ML; Premoli A

1992-11-01

402

Method for synthesizing 2-amino thizaoline  

UK PubMed Central (United Kingdom)

The invention relates to a method for synthesizing 2-aminothiazoline, which comprises the following steps: firstly, performing chlorinated reaction between ethanolamine and thionyl chloride in an organic solvent to generate 2-chloro-ethylamine hydrochloride and secondly, performing cyclization reaction between the 2-chloro-ethylamine hydrochloride and thiourea to generate the 2-aminothiazoline. Compared with the prior art, the method does not need introduce hydrogen chloride gas and concentrated hydrochloric acid to synthesize ethanolamine hydrochloride, thereby reducing reaction reagents and the reaction steps besides, the process route is more advanced, environment-friendly and safer, and the cyclization yield reaches more than 70 percent.

BINLIN SU; WANCHENG CHEN; ZHIWEI GAO; PIMING CHU; WEI SU; FUTANG KANG

403

Novel method for synthesizing aclatonium napadisilate  

UK PubMed Central (United Kingdom)

The invention discloses a novel method for synthesizing B naphthalene disulfonic acid ammonium milk bile, wherein, lactic acid and 1, 5-naphthalene disulfonic acid are used as original raw materials which are salified after esterification, acylation, and methyl ester reactions B naphthalene disulfonic acid ammonium milk bile is then directly and continuously synthesized separation and purification need not to be carried out on the reaction intermediate in each step. The preparing method has a scientific and reasonable process, a simple preparing process the three wastes (waste water, waste gas, and waste solid) are reduced simultaneously, cost is lowered the method is suitable to industrialization production.

TIANJIANG SUN; HONGGUO LU; JIANPENG FENG; HUIFENG YUAN; WENJING ZHAO; NIANQING ZHU; HAOGANG HUO; LIHU GAO; HUYUE ZHANG

404

Mirror movements of the left arm following peripheral damage to the preferred right arm.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Cerebral damage which renders the preferred arm useless may lead patients to use their non-preferred arm for everyday tasks including writing. In these circumstances, mirror writing and other mirror movements may occur. The present study on 10 formerly right-handed patients was carried out to determ...

Schott, G D

405

Arm 7 Based Robotic Arm Control By Electronic Gesture Recognition Unit Using Mems  

Directory of Open Access Journals (Sweden)

Full Text Available Mechatronics is one of the present trends in the era of computing in today’s system automation industry and control. The proposed project is one such attempt of implementing an accelerometer based system to communicate with an industrial robotic arm wirelessly. This project comprises of controlling of robotic arm powered with ARM7 based LPC1768 core. The LC1768 core has to be interfaced with DC motors of robotic arm to control the movements of robotic arm. MEMS is a three dimensional accelerometer sensor used for this purpose, this accelerometer sensor captures gestures of human-arm and produces three analog output voltages in three dimensional axes. And two flex sensors are used to control the gripper movement. For various movements of accelerometer and flex sensorscorresponding characters will be sent to the ARM7 core wirelessly using 2.4GHz RF module. And depending on the received character robotic arm can be controlled in Dynamic or Static mode by communicating with EEPROM using I2C protocol

K.Brahmani#1 , K.S.Roy#2 , Mahaboob Ali

2013-01-01

406

MORPHOLOGICAL CHANGES IN ASTACUS ASTACUS GONADS DURING THE REPRODUCTIVE CYCLE LES CHANGEMENTS MORPHOLOGIQUES DES GONADES D’ASTACUS ASTACUS PENDANT LE CYCLE REPRODUCTIF  

Directory of Open Access Journals (Sweden)

Full Text Available The reproductive cycle of Astacus astacus was described by the external observation of the gonads, recording changes in the gonadosomatic index (GSI) and by the histological analysis of the reproductive organs. A total of 37 males and 13 females of Astacus astacus were collected from the Vukovina gravel pit located at northwest Croatia from May 2003 until January 2004. All crayfish were mature with total body lengths between 7.84 and 13.7 cm and weights between 16 and 125 g. There was a pronounced difference between the GSI values of the sexes. GSI fluctuated within a very small range (between 0.2 and 1.5%) in males while in females it increased up to 12.3% during the mating season. The external appearance of the testes and ovaries during the reproductive cycle was compared with the histological sections of germ cells in the testes, the vas deferens and ovaries. Besides the germinative cells, the morphological changes in testis and vasa deferentia of A. astacus extended also to the connective tissue and secretory epithelium. The maturation of germinative cells was synchronized, both in testes and ovaries. Le cycle reproductif d’Astacus astacus a été décrit par l’observation externe des gonades, en enregistrant les changements de l’indexe gonadosomatique (GSI), et par l’analyse histologique des organes reproductifs. De mai 2003 à janvier 2004, 37 mâles et 13 femelles d’Astacus astacus ont prélevées dans une mine de gravier près de Vukovina qui se trouve au Nord Ouest de la Croatie. Toutes les écrevisses récoltées étaient mûres, mesuraient de 7,84 à 13,7 cm de longueur totale et pesaient de 16 à 125 g. Il y a une différence accentuée entre les valeurs de GSI des deux sexes. Chez les mâles les valeurs de GSI ont oscillé sur une toute petite amplitude (entre 0,2 et 1,5%) tandis que chez les femelles il a atteint 12,3% pendant la période reproductive. L’apparence externe des testicules et des ovaires pendant le cycle reproductif a été comparée aux coupes histologiques des cellules germinatives dans les testicules, les canaux déférents et les ovaires. Des changements morphologiques sont observés sur les testicules, les canaux déférents et les ovaires et s’étendent au tissu connectif et à l’épithélium sécréteur. La maturation des cellules germinatives est synchronisée dans les testicules aussi bien que dans les ovaires.

LUCI? A.; ERBEN R.; LACKOVI? G.

2008-01-01

407

Transient Spiral Arms in Isothermal Stellar Systems  

CERN Document Server

We begin by recalling the isothermal, collisionless, disc-halo. The disc component is the Mestel disc. Subsequently we introduce spiral arms to such an isothermal disc-halo system that are co-moving in the mean with an axi-symmetric background. These correspond to a similar disturbance in the halo, which is comprised of spiral structures on cones. The arms are necessarily transient due to the differential winding in the disc and their gradual destruction is described. Although the spiral potentials are weak compared to the axi-symmetric potential the arms are not propagating waves on the background, but rather co-move with it. They have an effect disproportionate to their relative magnitude on the gas distribution in the disc. The gas accumulates on the outside leading edge of the 'stellar' arm and an arm-interarm modulation of up to 100% is possible. Compatible isothermal, scale-free, distribution functions are found either exactly or approximately for all of the collisionless components of the disc-halo sys...

Henriksen, R N

2012-01-01

408

Dual trailing arm vehicle suspension system  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a vehicle suspension system adapted to be interposed between a vehicle frame and at least two wheels arranged one in advance of the other on a side of the vehicle frame; the suspension system including: (a) at least two axles on a side of the vehicle frame for independently rotatably mounting each of the wheels; (b) at least two trailing arms, each of the arms being attached at one end to a respective axle and extending forwardly from the axle wherein the number of the trailing arms does not exceed the number of axles; (c) at least two pivot means mounted on the vehicle frame and connected to the other end of the trailing arms for pivotally mounting the vehicle frame wherein the number of the pivot means, does not exceed the number of axles; (d) lever means attached to and extending outwardly from each of the pivot means for pivotal movement with the pivot means means in relationship to movement of the trailing arms, with the length of the lever means being independent of the spacing between the axles; and (e) elastomer spring means extending between and pivotally mounted on the lever means for absorbing and balancing the forces exerted on the wheels particularly during braking and when encountering variations in the road surface.

Weitzenhof, D.A.; Sayre, C.F.

1986-11-18

409

Representation of virtual arm movements in precuneus.  

UK PubMed Central (United Kingdom)

Arm movements can easily be adapted to different biomechanical constraints. However, the cortical representation of the processing of visual input and its transformation into motor commands remains poorly understood. In a visuo-motor dissociation paradigm, subjects were presented with a 3-D computer-graphical representation of a human arm, presenting movements of the subjects' right arm either as right or left arm. In order to isolate possible effects of coordinate transformations, coordinate mirroring at the body midline was implemented independently. In each of the resulting four conditions, 10 normal, right-handed subjects performed three runs of circular movements, while being scanned with O(15)-Butanol-PET. Kinematic analysis included orientation and accuracy of a fitted ellipsoid trajectory. Imaging analysis was performed with SPM 99 with activations threshold at P < 0.0001 (not corrected). The shape of the trajectory was dependent on the laterality of the arm, irrespective of movement mirroring, and accompanied by a robust activation difference in the contralateral precuneus. Movement mirroring decreased movement accuracy, which was related to increased activation in the left insula. Those two movement conditions that cannot be observed in reality were related to an activation focus at the left middle temporal gyrus, but showed no influence on movement kinematics. These findings demonstrate the prominent role of the precuneus for mediating visuo-motor transformations and have implications for the use of mirror therapy and virtual reality techniques, especially avatars, such as Nintendo Wii in neurorehabilitation.

Dohle C; Stephan KM; Valvoda JT; Hosseiny O; Tellmann L; Kuhlen T; Seitz RJ; Freund HJ

2011-02-01

410

Representation of virtual arm movements in precuneus.  

Science.gov (United States)

Arm movements can easily be adapted to different biomechanical constraints. However, the cortical representation of the processing of visual input and its transformation into motor commands remains poorly understood. In a visuo-motor dissociation paradigm, subjects were presented with a 3-D computer-graphical representation of a human arm, presenting movements of the subjects' right arm either as right or left arm. In order to isolate possible effects of coordinate transformations, coordinate mirroring at the body midline was implemented independently. In each of the resulting four conditions, 10 normal, right-handed subjects performed three runs of circular movements, while being scanned with O(15)-Butanol-PET. Kinematic analysis included orientation and accuracy of a fitted ellipsoid trajectory. Imaging analysis was performed with SPM 99 with activations threshold at P < 0.0001 (not corrected). The shape of the trajectory was dependent on the laterality of the arm, irrespective of movement mirroring, and accompanied by a robust activation difference in the contralateral precuneus. Movement mirroring decreased movement accuracy, which was related to increased activation in the left insula. Those two movement conditions that cannot be observed in reality were related to an activation focus at the left middle temporal gyrus, but showed no influence on movement kinematics. These findings demonstrate the prominent role of the precuneus for mediating visuo-motor transformations and have implications for the use of mirror therapy and virtual reality techniques, especially avatars, such as Nintendo Wii in neurorehabilitation. PMID:21188363

Dohle, Christian; Stephan, Klaus Martin; Valvoda, Jakob T; Hosseiny, Omid; Tellmann, Lutz; Kuhlen, Torsten; Seitz, Rüdiger J; Freund, Hans-Joachim

2010-12-25

411

Syntheses of novel substituted-boranophosphate nucleosides.  

UK PubMed Central (United Kingdom)

A number of substituted (borano) nucleic acids, 3'-[diethylphosphite(cyano, carboxy, or carbamoyl) borano] deoxynucleosides (3a-4c) and 5'-[diethylphosphite(cyano or carboxy) borano] deoxynucleosides (6a-7d) were prepared by a variety of synthetic procedures. The syntheses of the pyrophosphates (2a-2c), as precursors for 3a-4c, are also described.

Vyakaranam K; Rana G; Spielvogel BF; Maguire JA; Hosmane NS

2002-01-01

412

Integrated Radio Frequency Synthesizers for Wireless Applications  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This thesis consists of six publications and an overview of the research topic, which is also a summary of the work. The research described in this thesis concentrates on the design of phase-locked loop radio frequency synthesizers for wireless applications. In particular, the focus is on the implem...

Ahola, Rami

413

Multi-view synthesized aperture radar  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This article considers synthesized aperture radar (SAR), developed and manufactured in Radio Astronomy Institute of Ukrainian Academy of Sciences. SAR operates in 3 cm frequency band and it intended for obtaining multi-view images from light-motor planes. Technical and scientific solutions found dur...

Bezvesilniy, O. O.; Institute of Radio Astronomy of NASU; Vavriv, D. M.; Institute of Radio Astronomy of NASU

414

Semi-synthesizing method for polyenic taxusol  

UK PubMed Central (United Kingdom)

The invention discloses a semisynthesis method for polyenic taxusol. The method is to perform condensation reaction between 10-deacetylate baccatin (10-DAB) and synthesized C-13 side chain hydrolysate, open oxazoline rings, inoculate butoxycarbonyl on nitrogen of a side chain, and finally remove protection on a 7 site and a 10 site to obtain the polyenic taxusol.

XIN SHEN; LIXIN LIAO; FUXING LIN; XIAO HE; JIDONG YANG; HUAXING ZHAN

415

Method and apparatus for synthesizing filamentary structures  

Energy Technology Data Exchange (ETDEWEB)

Method and apparatus for producing filamentary structures. The structures include single-walled nanotubes. The method includes combusting hydrocarbon fuel and oxygen to establish a non-sooting flame and providing an unsupported catalyst to synthesize the filamentary structure in a post-flame region of the flame. Residence time is selected to favor filamentary structure growth.

Height, Murray J. (Somerville, MA); Howard, Jack B. (Winchester, MA); Vandersande, John B. (Newbury, MA)

2008-02-26

416

15N-amino acids syntheses  

International Nuclear Information System (INIS)

4 syntheses of 15N-amino acids are presented: (1) ammonolysis of ?-halogenated acids with H15NO3, (2) hydrolysis of hydantoin derivatives using 15NH4HCO3, (3) synthesis with phthalimide-15N potassium and (4) synthesis with acetamino-15N diethyl malonate

1983-06-01

417

Improvement of Twin-Arm Birateral Servomanipulator  

Energy Technology Data Exchange (ETDEWEB)

The Prototype-II Twin-Arm Birateral Servo-Manipulator developed by PNC has been evaluated by apply to remote handling and maintenance test from November, 1986 to March, 1988 in the Engineering Demonstration Facility III(EDF-III). Above test results showed that there were no major problems to apply the Prototype-II Servo-Manipulator to the hot facility. However, to obtain higher operability, some modifications were conducted on the Prototype-II Servo-Maipulator based on the analysis of test results, such as; (1) Reduce the master arm operation force (2) Improve the force-feedback function and (3) Enlarge the motion range of slave arm wrist portion. The evaluation test results showed the significant improvement of operability compared with the results of same kinds of test which was conducted before modification. This paper presents the substance of the Prototype-II Servo-Manipulator modification.

Fujita, Yuji; Wada, Takao; Kawakami, Hideo; Omori, Eiichi; Hayashi, Shotaro

1988-12-01

418

Spiral arms, comets and terrestrial catastrophism  

Energy Technology Data Exchange (ETDEWEB)

A review is presented of an hypothesis of terrestrial catastrophism in which comets grow in molecular clouds and are captured by the Sun as it passes through the spiral arms of the Galaxy. Assuming that comets are a major supplier of the Earth-crossing (Appollo) asteroid population, the latter fluctuates correspondingly and leads to episodes of terrestrial bombardment. Changes in the rotational momentum of core and mantle, generated by impacts, lead to episodes of magnetic field reversal and tectonic activity, while surface phenomena lead to ice-ages and mass extinctions. An episodic geophysical history with an interstellar connection is thus implied. If comets in spiral arms are necessary intermediaries in the process of star formation, the theory also has implications relating to early solar system history and galactic chemistry. These aspects are briefly discussed with special reference to the nature of spiral arms.

Clube, S.V.M.; Napier, W.M. (Royal Observatory, Edinburgh (UK))

1982-03-01

419

Molecular clouds in the Carina arm  

Energy Technology Data Exchange (ETDEWEB)

Results from the first large-scale survey in the CO(J = 1 ..-->.. 0) line of the Vela-Carina-Centaurus region of the Southern Milky Way are reported. The observations, were spaced every beamwidth (0.125/sup 0/) in the range 270/sup 0/ less than or equal to I less than or equal to 300/sup 0/ and -1/sup 0/ less than or equal to b less than or equal to 1/sup 0/, with latitude extensions to cover all Carina arm (I > 280/sup 0/) emission beyond the absolute value of b = 1/sup 0/. In a concurrent survey every half-degree in latitude and longitude was sampled in the range 270/sup 0/ less than or equal to I less than or equal to 300/sup 0/ and -5/sup 0/ less than or equal to b less than or equal to 5/sup 0/ at a spatial resolution of 0.5/sup 0/. Both surveys had a spectral coverage of 330 km s/sup -1/ with a resolution of 1.3 km s/sup -1/. The Carina arm dominates the data. Its abrupt tangent at I approx. = 280/sup 0/ and characteristic loop in the I,v diagram are unmistakable evidence for CO spiral structure. When the emission is integrated over velocity and latitude, the height of the setup seen in the tangent direction suggests that the arm-interarm contrast is at least 13 to 1. Spatial maps of the arm exhibit a projected narrowing in latitude of the CO layer with increasing kinematic distance. Comparison of the CO and HI data shows close agreement between these two species in a segment of the arm lying outside the solar circle (R/sub 0/ = 10 kpc); within R/sub 0/ the arm is more difficult to trace in HI than in CO.

Grabelsky, D.A.

1986-01-01

420

Chromium(III) complexes for photochemical nitric oxide generation from coordinated nitrite: synthesis and photochemistry of macrocyclic complexes with pendant chromophores, trans-[Cr(L)(ONO)(2)]BF(4).  

UK PubMed Central (United Kingdom)

Several new dinitritochromium(III) complexes of the type trans-[Cr(L)(ONO)(2)]BF(4), where L is a derivative of the macrocyclic ligand cyclam having pendant aromatic chromophores attached (L = 5,7-dimethyl-6-(substituted)-1,4,8,11-tetraazacyclotetradecane), have been prepared and characterized. Photoexcitation of aqueous solutions containing these complexes at wavelengths corresponding to the pendant chromophore absorption bands led to the generation of NO as detected by an electrochemical sensor. Photophysical data show that the expected fluorescence of the pendant chromophores is largely quenched when the macrocyclic ligand is coordinated to these Cr(III) centers, and this is interpreted in terms of fast energy transfer processes from the ligand-centered pipi states to the Cr(III)-centered ligand field states leading to subsequent cleavage of the Cr(III)-coordinated nitrito ligand. Thus, the chromophores tethered to the coordinated cyclam serve as light-gathering antennae for the intramolecular sensitization of the NO-generating photoreactions at the metal center.

Derosa F; Bu X; Ford PC

2005-06-01

 
 
 
 
421

Side-arm phase-conjugated laser  

Energy Technology Data Exchange (ETDEWEB)

A phase-conjugated Q-switched laser is described including: a starter cavity defined by opposed reflectors; a laser active material in the starter cavity; a pump for the laser active material; a side-arm containing a phase conjugate mirror consisting of a lens and a stimulated Brillouin scattering cell; means for optically coupling the starter cavity to the side-arm and including a quarterwave plate and a polarizer in the starter cavity, wherein the cell acts as a Q-switch by undergoing stimulated Brillouin scattering when the laser active material is pumped by the pump and a laser beam of sufficient power is reached.

Fukuda, R.C.; Chandra, S.

1987-11-24

422

HALOGEN POPCORN MAKER WITH STIRRING ARM  

UK PubMed Central (United Kingdom)

A halogen popcorn maker with stirring arm includes a base, an aluminium container and a transparent lid. A halogen tube, a thermostat and a synchronised machine are installed in the base. A stirring arm is fixed to the aluminium container by a bolt and a bolt nut where the bolt is connected to the synchronised machine by a connecting shaft. The present invention allows popcorn to be heated and popped evenly without being burnt. In addition, the popcorn maker is easy for dismantlement in the purpose of washing.

LAM ENOCH

423

The ARM unpiloted aerospace vehicle (UAV) program  

Energy Technology Data Exchange (ETDEWEB)

Unmanned aerospace vehicles (UAVs) are an important complement to the DOE`s Atmospheric Radiation Measurement (ARM) Program. ARM is primarily a ground-based program designed to extensively quantify the radiometric and meteorological properties of an atmospheric column. There is a need for airborne measurements of radiative profiles, especially flux at the tropopause, cloud properties, and upper troposphere water vapor. There is also a need for multi-day measurements at the tropopause; for example, in the tropics, at 20 km for over 24 hours. UAVs offer the greatest potential for long endurance at high altitudes and may be less expensive than piloted flights. 2 figs.

Sowle, D. [Mission Research Corporation, Santa Barbara, CA (United States)

1995-09-01

424

After Arizona: Military Musicians in the Second World War Après Arizona: les musiciens dans la marine américaine pendant la Seconde Guerre mondiale  

Directory of Open Access Journals (Sweden)

Full Text Available Cet article traite du rôle des musiciens dans la marine américaine pendant la Seconde Guerre mondiale. L’histoire de l’USS Arizona — et de son orchestre, noyé avec le cuirassé lors de l’attaque surprise des forces japonaises — étant bien connue, je m’appuie sur cet exemple comme point de départ afin de contextualiser la situation des musiciens militaires après les événements de Pearl Harbor, en décembre 1941. Dans le sillage de ce grand moment de l’Histoire, j’évoque ici des histoires à une autre échelle, celle de la « micro-histoire »— celle d’un militaire seul au milieu d’autres militaires. À travers les lettres échangées entre des recrues ayant suivi ensemble la même formation, je trace ici leurs expériences de guerre en tant qu’artistes, ainsi que les divers conflits pratiques et idéologiques qui se manifestent dans la tension entre l’art musical et l’art martial.

Rosemary Peters

2012-01-01

425

Synthesis and luminescence properties of Cr(III) complexes with cyclam-type ligands having pendant chromophores, trans-[Cr(L)Cl(2)]Cl.  

UK PubMed Central (United Kingdom)

The synthesis and spectroscopic properties of new cyclam-type ligands 5,7-dimethyl-6-R-1,4,8,11-tetraazacyclotetradecane (L), where R is a pendant chromophore such as an anthracene derivative, are reported. These ligands were prepared according to a nickel(II) template procedure, and the X-ray crystal structures of several Ni(II) intermediates are described. Reaction of the free base ligands L with CrCl(3)x3THF resulted in facile formation of trans-[Cr(L)Cl(2)]Cl complexes, and the structures and spectroscopic characterizations of these complexes are also described. Examination of the photophysical properties of trans-[Cr(L)Cl(2)]Cl solutions at 77 K demonstrated the emission spectra to be dominated by phosphorescence from the ligand field doublet of the chromium(III) center. This also applies to the Cr(III) complex trans-[Cr(mac)Cl(2)]Cl, where mac is the anthracene derivative 5,7-dimethyl-6-anthracenylcyclam. Excitation into the pi-pi(*) states of the anthracene leads to marked quenching of the fluorescence from this chromophore and sensitized phosphorescence from the metal-centered doublet state.

Derosa F; Bu X; Pohaku K; Ford PC

2005-06-01

426

Génotypage du virus de la rougeole par PCR en temps réel: Cas des souches virales isolées au Maroc pendant la saison 2004-2005  

Directory of Open Access Journals (Sweden)

Full Text Available Le génotypage du virus de la rougeole (VR) est un outil important dans la surveillance de la rougeole. Il permet d’identifier l’origine du virus, ses voies de transmission et d’évaluer les programmes de vaccination. Vu l’importance du génotypage du VR dans le programme de l’élimination de la rougeole, une technique rapide a été développée. Cette technique se base sur l’identification des génotypes par PCR en temps réel, les différents génotypes sont distingués par leur température de fusion (Tm). Cette méthode constitue une alternative efficace pour l’investigation des épidémies de rougeole dans les pays en phase d’élimination.Les souches du virus de la rougeole isolées pendant la saison 2004-2005 ont été identifiées par PCR en temps réel puis confirmées par le séquençage des gènes H et N. cette étude, a permis de montrer une rapide diversification des génotypes qui circulent au Maroc. Parmi ces génotypes, certains sont importés de l’Afrique de l’Ouest et de l’Europe, d’autres correspondent à la souche autochtone. Ces résultats montrent la nécessité de renforcer la couverture vaccinale et d’introduire une nouvelle stratégie de vaccination dans le but d’éliminer la maladie.

Amal Alla; Diane Waku-Kouomou

2007-01-01

427

Poly(?-caprolactone)-based copolymers bearing pendant cyclic ketals and reactive acrylates for the fabrication of photocrosslinked elastomers.  

Science.gov (United States)

Block copolymers of poly(ethylene glycol) and poly(?-caprolactone) (PCL) with chemically addressable functional groups were synthesized and characterized. Ring-opening polymerization of ?-caprolactone (CL) and 1,4,8-trioxaspiro-[4,6]-9-undecanone (TSU) using ?-methoxy, ?-hydroxyl poly(ethylene glycol) as the initiator afforded a copolymer with cyclic ketals being randomly distributed in the hydrophobic PCL block. At an initiator/catalyst molar ratio of 10/1 and a TSU/CL weight ratio of 1/4, a ketal-carrying copolymer (ECT2-CK) with Mn of 52kDa and a ketal content of 15mol.% was obtained. Quantitative side-chain deacetalization revealed the reactive ketones without noticeable polymer degradation. In our study, 10mol.% of cyclic ketals were deprotected and the ketone-containing copolymer was designated as ECT2-CO. Reaction of ECT2-CO with 2-(2-(aminooxy)acetoxy)-ethyl acrylate gave rise to an acrylated product (ECT2-AC) containing an estimated 3-5 acrylate groups per chain. UV-initiated radical polymerization of ECT2-AC in dichloromethane resulted in a crosslinked network (xECT2-AC). Thermal and morphological analyses employing differential scanning calorimetry and atomic force microscopy operated in PeakForce Tapping mode revealed the semicrystalline nature of the network, which contained stiff crystalline lamellae dispersed in a softer amorphous interstitial. Macroscopic and nanoscale mechanical characterizations showed that ECT2-CK exhibited a significantly lower modulus than PCL of a similar molecular weight. Whereas ECT2-CK undergoes a plastic deformation with a distinct yield point and a cold-drawing region, xECT2-AC exhibits a compliant, elastomeric deformation with a Young's modulus of 0.5±0.1MPa at 37°C. When properly processed, the crosslinked network exhibited shape-memory behaviors, with shape fixity and shape recovery values close to 1 and a shape recovery time of less than 4s at 37°C. In vitro studies showed that xECT2-AC films did not induce any cytotoxic effects on the cultured mesenchymal stem cells. The crosslinkable polyester copolymers can be potentially used as tissue engineering scaffolds and minimally invasive medical devices. PMID:23770222

Yang, Xiaowei; Cui, Chengzhong; Tong, Zhixiang; Sabanayagam, Chandran R; Jia, Xinqiao

2013-06-14

428

Battery saving system for a frequency synthesizer  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a digital frequency synthesizer having a reference frequency source, sample and hold phase detector, voltage controlled oscillator and variable frequency divider, a power saving system comprising: a power source; and a power saving generator means generating a power saving signal having a predetermined duty cycle and period. The generator means is coupled between the synthesizer and the power source. The means is responsive to the hold timing periods of the phase detector to interrupt power to the reference frequency source and variable divider in synchronism with the establishment of the hold timing periods of the phase detector to conserve power yet maintain the voltage controlled oscillator output without deviation or interruption.

Borras, J.A.; Suarez, J.I.

1986-12-23

429

Synthesis of biotin-containing phosphoramidite linker with polyether spacer arm.  

Science.gov (United States)

A phosphoramidite linker unit, based on glycerol backbone and containing a biotin residue attached through a tetraethylene glycol spacer arm, was synthesized. DMTr-Glycidol and tetraethylene glycol were used as starting materials. After conversion of one of hydroxy groups in tetraethylene glycol into an amino group, the epoxy cycle in DMTr-glycidol was opened by this amino alcohol, resulting in the corresponding ether and some quantity of secondary amine. After attaching of biotin residue to the ether followed by phosphitylation, the desirable linker was obtained. The structure of the linker was confirmed by (1)H-(1)H COSY, (1)H-(13)C HSQC, (1)H-(13)C HMBC, (1)H-(15)N HSQC, and (1)H-(15)N HMBC spectra. The resulted phosphoramidite linker unit is suitable for use in common DNA synthesizers. This approach can be used for preparation of various modifiers containing reporter groups attached to the primary amino function using conventional procedures. PMID:21888541

Kayushin, Alexey; Demekhina, Alexandra; Korosteleva, Maria; Miroshnikov, Anatoly; Azhayev, Alex

430

Synthesis of biotin-containing phosphoramidite linker with polyether spacer arm.  

UK PubMed Central (United Kingdom)

A phosphoramidite linker unit, based on glycerol backbone and containing a biotin residue attached through a tetraethylene glycol spacer arm, was synthesized. DMTr-Glycidol and tetraethylene glycol were used as starting materials. After conversion of one of hydroxy groups in tetraethylene glycol into an amino group, the epoxy cycle in DMTr-glycidol was opened by this amino alcohol, resulting in the corresponding ether and some quantity of secondary amine. After attaching of biotin residue to the ether followed by phosphitylation, the desirable linker was obtained. The structure of the linker was confirmed by (1)H-(1)H COSY, (1)H-(13)C HSQC, (1)H-(13)C HMBC, (1)H-(15)N HSQC, and (1)H-(15)N HMBC spectra. The resulted phosphoramidite linker unit is suitable for use in common DNA synthesizers. This approach can be used for preparation of various modifiers containing reporter groups attached to the primary amino function using conventional procedures.

Kayushin A; Demekhina A; Korosteleva M; Miroshnikov A; Azhayev A

2011-07-01

431

Molecular trees: from syntheses towards applications  

Energy Technology Data Exchange (ETDEWEB)

Molecular trees, also called dendrimers, arborols, cauliflowers, cascades or hyperbranched molecules, have been synthesized since their first observation in 1978 by divergent, convergent or combined methods, with various functions on the branches. The potential applications of these nanoscopic molecules are in the fields of biology (gene therapy, virus mimicking an vectorization) and molecular materials sciences (new polymers, adhesion, liquid crystals, etc). (authors). 236 refs., 6 figs., 2 tabs., 8 schemes.

Ardoin, N.; Astruc, D. [Bordeaux-1 Univ., 33 - Talence (France)

1995-12-31

432

Molecular trees: from syntheses towards applications  

International Nuclear Information System (INIS)

Molecular trees, also called dendrimers, arborols, cauliflowers, cascades or hyperbranched molecules, have been synthesized since their first observation in 1978 by divergent, convergent or combined methods, with various functions on the branches. The potential applications of these nanoscopic molecules are in the fields of biology (gene therapy, virus mimicking an vectorization) and molecular materials sciences (new polymers, adhesion, liquid crystals, etc). (authors). 236 refs., 6 figs., 2 tabs., 8 schemes.

1995-01-01

433

Method for synthesizing ultrafine powder materials  

Energy Technology Data Exchange (ETDEWEB)

A method for synthesizing ultrafine powder materials, for example, ceramic and metal powders, comprises admitting gaseous reactants from which the powder material is to be formed into a vacuum reaction chamber maintained at a pressure less than atmospheric and at a temperature less than about 400.degree. K. (127.degree.C.). The gaseous reactants are directed through a glow discharge provided in the vacuum reaction chamber to form the ultrafine powder material.

Buss, Richard J. (Albuquerque, NM); Ho, Pauline (Albuquerque, NM)

1988-01-01

434

Nanocrystalline diamond synthesized from C60  

Energy Technology Data Exchange (ETDEWEB)

A bulk sample of nanocrystalline cubic diamond with crystallite sizes of 5-12 nm was synthesized from fullerene C{sub 60} at 20(1) GPa and 2000 C using a multi-anvil apparatus. The new material is at least as hard as single crystal diamond. It was found that nanocrystalline diamond at high temperature and ambient pressure kinetically is more stable with respect to graphitization than usual diamonds.

Dubrovinskaia, N.; Dubrovinsky, L.; Langehorst, F.; Jacobsen, S.; Liebske, C. (Bayreuth)

2010-11-30

435

Efficient syntheses of deuterium labelled epinines  

International Nuclear Information System (INIS)

[en] Syntheses of N-methyl-2-(3,4-dihydroxyphenyl)ethylamine hydrochlorides (epinines) labeled with deuterium in the ring, in the N-methyl group and both in the ring and N-methyl group are described. The N-trideuteromethyl group was generated by the LiAlD4 reduction of the corresponding carbamate while the ring deuterated epinines were produced by the DCl catalyzed exchange in D2O of the corresponding ring unlabeled epinines. (author)

1985-01-01

436

Total syntheses of (-)-haemanthidine, (+)-pretazettine, and (+)-tazettine.  

UK PubMed Central (United Kingdom)

[structures: see text] The total syntheses of the amaryllidaceae alkaloids haemanthidine, pretazettine, and tazettine as optically pure enantiomers are reported. Using D-mannose as the starting material, the critical relative stereochemical relationships are established with an intramolecular nitrone-alkene cycloaddition reaction. The synthetic route leads successively to (-)-haemanthidine and then to (+)-pretazettine and (+)-tazettine, taking advantage of the well-established complex relationships among these three alkaloids.

Baldwin SW; Debenham JS

2000-01-01

437

Total syntheses of (-)-haemanthidine, (+)-pretazettine, and (+)-tazettine.  

Science.gov (United States)

[structures: see text] The total syntheses of the amaryllidaceae alkaloids haemanthidine, pretazettine, and tazettine as optically pure enantiomers are reported. Using D-mannose as the starting material, the critical relative stereochemical relationships are established with an intramolecular nitrone-alkene cycloaddition reaction. The synthetic route leads successively to (-)-haemanthidine and then to (+)-pretazettine and (+)-tazettine, taking advantage of the well-established complex relationships among these three alkaloids. PMID:10814256

Baldwin, S W; Debenham, J S

2000-01-27

438

SYNTHESES OF METHYLENEDIANILINES OVER THE ZEOLITE CATALYSTS  

Directory of Open Access Journals (Sweden)

Full Text Available Syntheses of methylenedianilines over zeolites with various structures were studied. It was foundout that the most selective catalyst for the synthesis of 4,4´-methylenedianiline isomer was zeoliteY. Further, the kinetic data showed that initial N,N´-diphenylmethylenediamine reacted over zeolitecatalysts by even one order of magnitude faster that the intermediate product 4-amino-N-benzylaniline.The most suitable temperature range

Ji?í Trejbal

2010-01-01

439

Facile syntheses of monodisperse ultrasmall Au clusters.  

Science.gov (United States)

During our effort to synthesize the tetrahedral Au20 cluster, we found a facile synthetic route to prepare monodisperse suspensions of ultrasmall Au clusters AuN (N Au10 and Au8 clusters. The simplicity of our synthetic method makes it suitable for large-scale production of nearly monodisperse ultrasmall Au clusters. It is suggested that diphosphines provide a set of flexible ligands to allow size-controlled synthesis of Au nanoparticles. PMID:17064088

Bertino, Massimo F; Sun, Zhong-Ming; Zhang, Rui; Wang, Lai-Sheng

2006-11-01

440

Field Campaign Guidelines (ARM Climate Research Facility)  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this document is to establish a common set of guidelines for the Atmospheric Radiation Measurement (ARM) Climate Research Facility for planning, executing, and closing out field campaigns. The steps that guide individual field campaigns are described in the Field Campaign Tracking database tool and are tailored to meet the scope of each specific field campaign.

Voyles, JW

2011-01-17