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1

Biological evaluation of 153Sm and 166Ho complexes with tetraazamacrocycles containing methylcarboxylate and/or methylphosphonate pendant arms  

International Nuclear Information System (INIS)

153Sm and 166Ho complexes with two series of tetraazamacrocyclic ligands containing methylcarboxylate and/or methylphosphonate pendant arms were synthesized and their charge, lipophilicity, protein binding and in vitro and in vivo behaviour evaluated. The first series has the same backbone, a 14-membered tetraazamacrocycle containing a pyridine unit with different pendant arms, namely methylcarboxylates (ac3py14) or methylphosphonates (MeP2py14 and P3py14). The second series comprises 12- to 14-membered tetraazamacrocycles having methylcarboxylates and/or methylphosphonates as pendant arms (trans-DO2A2P, TRITA, TRITP, TETA and TETP). The 153Sm/166Ho complexes with the 14-membered tetraazamacrocycles containing the pyridine unit are neutral, hydrophilic, have a significant plasmatic protein binding, are unstable in vivo and present a slow rate of radioactivity excretion and high hepatic retention. 153Sm/166Ho complexes with the 12- to 14-membered tetraazamacrocycles are quantitatively prepared, except those with TETP. These complexes are hydrophilic, have an overall negative charge and present a medium to low plasmatic protein binding. The 153Sm/166Ho-trans-DO2A2P, 153Sm/166Ho-TRITA and 166Ho-TRITP complexes are stable in vitro and in vivo, presenting a rapid clearance from main organs and a high rate of whole body radioactivity excretion. Biological profile of 153Sm/166Ho-TRITA complexes makes them promising candidates for therapy when conjugated to a biomolecule, while 166Ho-TRITP is potentially useful for bone targeting due to its considerable uptake by bone. (orig.)

2007-01-01

2

Biological evaluation of {sup 153}Sm and {sup 166}Ho complexes with tetraazamacrocycles containing methylcarboxylate and/or methylphosphonate pendant arms  

Energy Technology Data Exchange (ETDEWEB)

{sup 153}Sm and {sup 166}Ho complexes with two series of tetraazamacrocyclic ligands containing methylcarboxylate and/or methylphosphonate pendant arms were synthesized and their charge, lipophilicity, protein binding and in vitro and in vivo behaviour evaluated. The first series has the same backbone, a 14-membered tetraazamacrocycle containing a pyridine unit with different pendant arms, namely methylcarboxylates (ac{sub 3}py14) or methylphosphonates (MeP{sub 2}py14 and P{sub 3}py14). The second series comprises 12- to 14-membered tetraazamacrocycles having methylcarboxylates and/or methylphosphonates as pendant arms (trans-DO2A2P, TRITA, TRITP, TETA and TETP). The {sup 153}Sm/{sup 166}Ho complexes with the 14-membered tetraazamacrocycles containing the pyridine unit are neutral, hydrophilic, have a significant plasmatic protein binding, are unstable in vivo and present a slow rate of radioactivity excretion and high hepatic retention. {sup 153}Sm/{sup 166}Ho complexes with the 12- to 14-membered tetraazamacrocycles are quantitatively prepared, except those with TETP. These complexes are hydrophilic, have an overall negative charge and present a medium to low plasmatic protein binding. The {sup 153}Sm/{sup 166}Ho-trans-DO2A2P, {sup 153}Sm/{sup 166}Ho-TRITA and {sup 166}Ho-TRITP complexes are stable in vitro and in vivo, presenting a rapid clearance from main organs and a high rate of whole body radioactivity excretion. Biological profile of {sup 153}Sm/{sup 166}Ho-TRITA complexes makes them promising candidates for therapy when conjugated to a biomolecule, while {sup 166}Ho-TRITP is potentially useful for bone targeting due to its considerable uptake by bone. (orig.)

Marques, F.; Gano, L.; Campello, M.P.; Lacerda, S.; Santos, I. [Inst. Tecnologico e Nuclear, Sacavem (Portugal)

2007-07-01

3

Oligomerized alpha-helical KALA peptides with pendant arms bearing cell-adhesion, DNA-binding and endosome-buffering domains as efficient gene transfection vectors.  

Science.gov (United States)

In this study, a number of KALA-based ?-helical peptides were designed and synthesized as non-viral gene carriers. The effects of lysine and histidine residues in the pendant arms and cell-binding RGD motif on DNA binding, particle size, zeta potential, cytotoxicity and gene expression efficiency were first explored. Increasing the lysine and histidine residues reduced particle size and increased zeta potential of DNA complexes, leading to greater gene expression efficiency. In addition, the introduction of RGD group further improved gene expression level. The peptide with optimal compositions, RGDN(3)K(6)H(3)CKHLAKALAKALAC (RC29), was then oligomerized to form di-, tri- and tetra-RC29 via disulfide linkage. Upon oligomerization, RC29 attained a 3-dimensional long ?-helical structure with pendant arm(s) extending transversally outwards. Each arm contains a cell-adhesion motif (RGD), DNA-binding and endosome-buffering domains(.) The ?-helicity of the oligomerized peptides was evaluated by circular dichroism (CD) spectroscopy, which showed that an increased oligomerization degree led to a stronger ?-helical structure. These peptides form complexes with DNA efficiently. The minimum size and maximum zeta potential of tri-RC29/DNA complexes was about 200 nm and 32.5 mV, respectively. In comparison, RC29 formed DNA complexes with a similar zeta potential, but particle size was significantly larger (355 nm). DNA complexes formed at pH 7.0 yielded higher gene expressions than those formed at pH 5.5 and 6.5. Among all the oligomerized peptides, tri-RC29 provided the highest gene expression efficiency, and its peak luciferase level was 1.5 times higher than that yielded by PEI at its optimal N/P ratio (i.e. 10). Moreover, oligomerized RC29/DNA complexes were less cytotoxic than PEI/DNA complexes. These ?-helical peptides can be promising carrier for delivery of therapeutic genes in the treatment of genetic disorders. PMID:22698722

Guo, Xin Dong; Wiradharma, Nikken; Liu, Shao Qiong; Zhang, Li Juan; Khan, Majad; Qian, Yu; Yang, Yi-Yan

2012-09-01

4

Europium(III) DOTA-derivatives having ketone donor pendant arms display dramatically slower water exchange  

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A series of new 1,4,7,10-tetraazacyclododecane-derivatives having a combination of amide and ketone donor groups as side-arms were prepared and their complexes with europium(III) studied in detail by high resolution NMR spectroscopy. The chemical shift of the Eu3+-bound water resonance, the chemical exchange saturation transfer (CEST) characteristics of the complexes, and the bound water residence lifetimes (?m) were found to vary dramatically with the chemical structure of the side-arms. Su...

Green, Kayla N.; Viswanathan, Subha; Rojas-quijano, Federico A.; Kovacs, Zoltan; Sherry, A. Dean

2011-01-01

5

Antibacterial, DNA interaction and cytotoxic activities of pendant-armed polyamine macrocyclic dinuclear nickel(II) and copper(II) complexes.  

Science.gov (United States)

A series of dinuclear nickel(II) and copper(II) complexes (1-6) of hexaaza macrocycles of 2,6-diformyl-4-methylphenol with three different benzoyl pendant-arms, 2,2'-benzoyliminodi(ethylamine) trihydrochloride (L), 2,2'-4-nitrobenzoyliminodi(ethylamine) trihydrochloride (L') and 2,2'-3,5-dinitrobenzoyliminodi(ethylamine) trihydrochloride (L?) have been synthesized and characterized by spectral methods. The electrochemical studies of these complexes depict two irreversible one electron reduction processes around E(1)pc=-0.62 to -0.76V and E(2)pc=-1.21 to -1.31, and nickel(II) complexes (1-3) exhibit two irreversible one electron oxidation processes around E(1)pa=1.08 to 1.14V and E(2)pa=1.71 to 1.74V. The room temperature magnetic moment values (?eff, 1.52-1.54 BM) indicate the presence of an antiferromagnetic interaction in the binuclear copper(II) complexes (4-6) which is also observed from the broad ESR spectra with a g value of 2.14-2.15. The synthesized complexes (1-6) were screened for their antibacterial activity. The results of DNA interaction studies indicate that the dinuclear complexes can bind to calf thymus DNA by intercalative mode and display efficient cleavage of plasmid DNA. Further, the cytotoxic activity of complexes 2, 5 and 6 on human liver adenocarcinoma (HepG2) cell line has been examined. Nuclear-chromatin cleavage has also been observed with PI staining and comet assays. PMID:24747866

Arthi, P; Haleel, A; Srinivasan, P; Prabhu, D; Arulvasu, C; Kalilur Rahiman, A

2014-08-14

6

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  

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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-1,4,7,10-tetraacetic acid), present as a racemic mixture of (alphaR) and (alphaS) enantiomers. The protonation constants of the ligand were determined by potentiometry, giving values close to H4dot...

Andre?, Joa?o P.; Bru?cher, Erno?; Kiraly, Robert; Carvalho, Rui A.; Ma?cke, Helmut; Geraldes, Carlos F. G. C.

2005-01-01

7

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

International Nuclear Information System (INIS)

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

2005-11-14

8

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

9

Zinc halide template effects on the construction of [1 + 1] flexible Schiff-base macrocyclic complexes having pendant-armed dialdehyde components.  

Science.gov (United States)

Two novel pendant-armed dialdehydes (1a and 1b) were prepared by a one-step reaction between 5-chloro-3-(chloromethyl)-2-hydroxybenzaldehyde/5-methyl-3-(chloromethyl)-2-hydroxybenzaldehyde and cyclohexylamine involving two nucleophilic substitutions, and they were used to react with 1,3-propanediamine to prepare Schiff-base macrocyclic complexes in the presence of ZnX2 salts (X = Cl, Br, and I). As a result, five dinuclear (2a, 2b, 3b, 4a, and 4b) and one mononuclear (3a) [1 + 1] flexible macrocyclic Zn(ii) complexes have been structurally and spectrally characterized. The zinc centers in three pairs of macrocyclic complexes have the common four-coordinate tetrahedral geometry with one or two coordinated halide ions, where the template Zn(ii) cations and the auxiliary halide anions with different sizes and coordination abilities are believed to play important roles in forming the resulting macrocyclic complexes. In addition, subtle alterations of electron-withdrawing and electron-donating substituted groups (Cl versus CH3) in the macrocyclic backbone result in different (1)H NMR and UV-vis spectra. PMID:24752191

Chen, Hui-Qing; Zhang, Kun; Jin, Chao; Huang, Wei

2014-06-14

10

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

11

Synthesis and characterization of Ni(II, Cu(II and Co(III complexes with polyamine-containing macrocycles bearing an aminoethyl pendant arm  

Directory of Open Access Journals (Sweden)

Full Text Available Reaction of [M(ppn2]X2 (where M = Cu(II, Ni(II, Co(II and ppn = 1,3-diaminopropane with formaldehyde and ethylenediamine in methanol results in the ready formation of a 16-membered macrocyclic complex. The complexes were characterized by elemental anlysis, IR, EPR, electronic spectral data, magnetic moments and conductance measurements. The Cu(II, Ni(II and Co(III complexes are coordinated axially with both pendant groups of the hexadentate macrocycle. These pendant donors are attached to the macrocycle by a carbon chain. The electrical conductivities of the Cu(II and Ni(II chelates indicated them to be 1:2 electrolytes whilst those of Co(III is a 1:3 electrolyte in DMSO. The EPR spectrum of the copper complex exhibited G at 3.66, which indicates a considerable exchange interaction in the complex. Spectroscopic evidence suggests that in all of the complexes the metal ion is in an octahedral environment.

K. S. SIDDIQI

2004-09-01

12

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 synthesized. As expected, its Ln(III) complexes exhibit structure analogy to the Ln(III) complexes of DOTA with one water molecule bound in the apical position. The Gd(III)-DOTAPP complex shows similar r...

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

2009-01-01

13

H5dotasa (=(alphaRS)-alpha-(carboxymethyl)-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid), an Asymmetrical Derivative of H4dota (=1,4,7,10-Tetraazacyclododecane-1,4,7,10-tetraacetic Acid) 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 at the C(alpha) atom of one of the four acetate pendant arms of H4dota (=1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid), present as a racemic mixture of (alphaR) and (alphaS) enantiomers. The protonation constants of the ligand were determined by potentiometry, giving values close to those of H4d...

Andre?, Joa?o p; Bru?cher, Erno?; Kiraly, Robert; Carvalho, Rui a; Ma?cke, Helmut; Geraldes, Carlos f  g  c

2005-01-01

14

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)

1996-06-01

15

Conjugated Polymers with Pendant Iniferter Units: Versatile Materials for Grafting  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A novel compound N-(N',N'-diethyldithiocarbamoylethylamidoethyl)aniline (NDDEAEA) was synthesized and fully characterized. Conjugated poly(NDDEAEA), consisting of N-substituted polyaniline (PANI) backbones with dithiocarbamate ester pendant groups (which can act as iniferters), was synthesized by both chemical and electrochemical polymerization. UV-initiated living polymerization was utilized to graft styrene, methacrylic acid (MAA), lauryl methacrylate, and acrylamido-2-methylpropa...

Ivanova-mitseva, Petya K.; Fragkou, Vasiliki; Lakshmi, Dhana; Whitcombe, Michael J.; Davis, Frank; Guerreiro, Antonio; Crayston, Joseph A.; Ivanova, Diana K.; Mitsev, Petar A.; Piletska, Elena V.; Piletsky, Sergey A.

2011-01-01

16

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)

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

17

Nonlinear oscillations of pendant drops  

International Nuclear Information System (INIS)

Whereas oscillations of free drops have been scrutinized for over a century, oscillations of supported (pendant or sessile) drops have only received limited attention to date. Here, the focus is on the axisymmetric, free oscillations of arbitrary amplitude of a viscous liquid drop of fixed volume V that is pendant from a solid rod of radius R and is surrounded by a dynamically inactive ambient gas. This nonlinear free boundary problem is solved by a method of lines using Galerkin/finite element analysis for discretization in space and an implicit, adaptive finite difference technique for discretization in time. The dynamics of such nonlinear oscillations are governed by four dimensionless groups: (1) a Reynolds number Re, (2) a gravitational Bond number G, (3) dimensionless drop volume V/R"3 or some other measure of drop size, and (4) a measure of initial drop deformation a/b. The change in frequency ?? of pendant drops with increasing initial deformation is drop size dependent. As the average linear size of pendant drops characterized by V"1"/"3 becomes large compared to the rod radius, V"1"/"3/R much-gt 1, ?? falls as a/b rises, in accordance with results for free drops. The dynamics of very small drops, i.e., ones for which V"1"/"3/R much-lt 1, however, are profoundly affected by the presence of the solid rod. For such small drops, ?? rises as a/b rises, a remarkable fact. The results show that for drops of a given size, the frequency is insignificantly affected by viscosity over a wide of range of Reynolds numbers. However, when Re falls below a critical value, the nature of drop motion changes from underdamped oscillations to an aperiodic return to the rest state (Abstract Truncated)

1994-09-01

18

Hg2+ detection by new anthracene pendant-arm derivatives of mixed N/S- and N/S/O-donor macrocycles: fluorescence, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and density functional theory studies.  

Science.gov (United States)

The optical response of four new anthracenylmethyl pendant-arm derivatives (L1-L4) of the macrocyclic ligands [12]aneNS(3), [12]aneNS(2)O, [15]aneNS(2)O(2), and [12]aneN(2)SO toward the metal ions Zn(2+), Cd(2+), Pb(2+), Cu(2+), Hg(2+), Ag(+), Fe(2+), Co(2+), Ni(2+), Mn(2+), Ca(2+), Na(+), Mg(2+), and K(+) was investigated in 1:1 (v/v) MeCN/H(2)O solutions. A strong chelation enhancement of quenching effect was observed on the fluorescent emission intensity of L2 as a consequence of the host-guest interaction with Hg(2+) and the formation of a 1:2 metal-to-ligand complex. Density functional theory calculations confirmed the formation of a sandwich-type complex between L2 and Hg(2+) as a favorable process. A matrix-assisted laser desorption/ionization (MALDI) time-of-flight mass spectrometry study using the four ligands as active MALDI probes was also performed. L1-L4 have also been explored as fluorescence chemosensors in microsamples using NANODROP technology. PMID:20715769

Mameli, Marta; Lippolis, Vito; Caltagirone, Claudia; Capelo, José Luis; Faza, Olalla Nieto; Lodeiro, Carlos

2010-09-20

19

Synthesis and characterization of complexes of Fe(III), Co(III), Ni(II), Cu(II), Zn(II) and UO22+ with p-tert-butylcalix(4)arene bearing two imine pendants linked through salicylyl moiety at the lower rim  

International Nuclear Information System (INIS)

Metal ion complexes of the double-armed p-tert-butylcalix(4)arene derivative possessing imine functionality linked through salicylyl moiety at the lower rim has been synthesized for the first time and characterized by analytical. spectral and magnetic methods. The 1,3-di-calix(4)arene-imine conjugate exhibits variable coordination behavior, from tetradentate to hexadentate, depending upon the metal ion to which it is bound, by always acting as di-anionic. While it uses both the ether oxygens of the pendants to coordinate in the case of Fe(III), Co(III) and Ni(II) complexes, it uses only the pendant salicylidene moieties in the case of Cu(II) and Zn(II) complexes. The Zn(II) complex catalysis ester hydrolysis through the formation of Zn(II)-hydroxo species. (author)

2009-11-01

20

Nanopod Formation Through Gold Nanoparticle Templated and Catalyzed Crosslinking of Polymers Bearing Pendant Propargyl Ethers  

Science.gov (United States)

A novel method for synthesizing polymer nanopods from a linear polymer bearing pendant propargyl ether groups, using gold nanoparticles as both the template and the catalyst for the crosslinking reaction, is reported. The transformations involved in the crosslinking process are unprecedented on the surface of a gold particle. A tentative crosslinking mechanism is proposed.

Zhang, Ke; Cutler, Joshua I.; Zhang, Jian; Zheng, Dan; Auyeung, Evelyn; Mirkin, Chad A.

2011-01-01

 
 
 
 
21

Nanopod Formation Through Gold Nanoparticle Templated and Catalyzed Crosslinking of Polymers Bearing Pendant Propargyl Ethers  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A novel method for synthesizing polymer nanopods from a linear polymer bearing pendant propargyl ether groups, using gold nanoparticles as both the template and the catalyst for the crosslinking reaction, is reported. The transformations involved in the crosslinking process are unprecedented on the surface of a gold particle. A tentative crosslinking mechanism is proposed.

Zhang, Ke; Cutler, Joshua I.; Zhang, Jian; Zheng, Dan; Auyeung, Evelyn; Mirkin, Chad A.

2010-01-01

22

Synthesis and ATRP of novel fluorinated aromatic monomer with pendant sulfonate group  

DEFF Research Database (Denmark)

Novel, fluorinated monomer with pendant sulfonate group was synthesized utilizing a two-step derivatization of 2,3,4,5,6-pentafluorostyrene (FS). The first step was a nucleophilic substitution of the fluorine atom in para position by hydroxyl group followed by sulfopropylation. The monomer was polymerized under aqueous ATRP conditions to yield phenyl-fluorinated aromatic homopolymer bearing pendant sulfonates on each repeating unit. Furthermore, this polymer was used as macroinitiator for the ATRP of poly(ethylene glycol) methacrylate. The polymers were characterized by 1H NMR, SEC and FTIR analyses. Their thermal properties were evaluated by differential scanning calorimetry and thermal gravimetric analyses.

Dimitrov, Ivaylo; Jankova Atanasova, Katja

2013-01-01

23

Monosubstituted arylimido hexamolybdates containing pendant amino groups: synthesis and structural characterization.  

Science.gov (United States)

Three novel rigid-rod conjugated organic-POM hybrids (1, 2 and 3) containing pendant amino terminus, with different rod lengths and different substituents on the rod, have been respectively synthesized via one-pot reaction of hexamolybdate and the corresponding aromatic diamine (for 1 and 2) and reaction of octamolybdate and the corresponding aromatic diamine dihydrochloride (for 3) with N,N'-dicyclohexylcarbodiimide (DCC) as a dehydrating agent. These complexes have been characterized by UV/Vis, IR, (1)H NMR, ESI and single-crystal X-ray diffraction techniques. The influences of the rod length and substituents on the properties of these compounds have been systematically investigated, which provide necessary information for further preparations of complicated hybrid materials via reactions with pendant amino groups. PMID:21528132

Zhu, Yi; Xiao, Zicheng; Wang, Longsheng; Yin, Panchao; Hao, Jian; Wei, Yongge; Wang, Yuan

2011-07-28

24

Thermally Stable Perfluorinated Polyimides with Pendant Perfluorinated Aromatic Unit for Photonic Applications  

Science.gov (United States)

We have designed and synthesized novel thermally stable perfluorinated polyimides with pendant perfluorinated aromatic unit for photonic applications. At first, we developed a new synthetic route to a perfluorinated aromatic diamine by protecting-deprotecting as well as by nucleophilic bromine displacement reactions, affording a new diamine with a pendant perfluorinated aromatic unit. Its chemical structure was identified by 1H-, 19F- and 13C-NMR spectroscopies as well as mass spectrometry. Novel fluorinated polyimides were prepared by condensation polymerization of the present fluorinated diamine with various dianhydrides. The resultant polyimides are thermally stable over 400°C. The refractive index and birefringence of the resultant polyimides are 1.5844 ~ 1.5040 and 0.01 ~ 0.03 at 633 nm, respectively.

Park, Jin Kyu; Song, Bok Ju; Lee, Dong-Hun; Song, Young-Bae; Oh, Jae Buem; Hong, Ji-Sook; Kim, Hwan Kyu

25

Breakup of a pendant magnetic drop  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We report experiments on a millimeter-sized pendant drop of ferrofluid in a horizontal magnetic field. The initial drop size is chosen just below the breakup threshold under gravity. As the magnetic field is increased, the drop tilts in order to align with the direction of the total volume force that is exerted on it: weight plus magnetic force. The breakup is controlled by a generalized Bond number based on this total force and on the radius of the neck of the drop. The evolution of drop sha...

Havard, N.; Risso, Frederic; Tordjeman, Philippe

2013-01-01

26

Macroporous copolymer matrix: 1. Effectiveness of different diisocyanate spacer arms to bind cyclodextrins.  

Science.gov (United States)

Cross-linked macroporous beaded polymer matrices, with pendant hydroxyl groups, were synthesized by the copolymerization of 2-hydroxyethyl methacrylate and ethylene glycol dimethacrylate using suspension polymerization methodology. Novel affinity chromatography matrices were synthesized using various diisocyanates as bifunctional reagents to couple the macroporous polymeric supports, of controlled particle size distribution, with alpha and beta-cyclodextrins. The optimal conditions to couple the hydroxyl groups of cyclodextrin (ligand) and the polymeric supports through urethane linkages were established iteratively using various diisocyanates. Efficacy of ligand binding on the matrix and nonspecific interactions of the synthesized affinity matrices were evaluated to establish the best support and spacer arm. 2,4-Tolylene diisocyanate was established as the best spacer arm on the basis of high ligand binding and low nonspecific interactions. The characteristics of the synthesized affinity matrices toward the adsorption of alpha and beta-cyclodextrin glycosyltransferase (CGTase) were investigated. The binding of beta-CGTase was the highest on affinity matrices with the polymeric methylene diisocyanate spacer. The optimal conditions to regenerate the matrices were also established. PMID:11777382

Nayak, D P; Kotha, A M; Yemul, O S; Ponrathnam, S; Raman, R C

2001-01-01

27

Breakup of a pendant magnetic drop.  

Science.gov (United States)

We report experiments on a millimeter-sized pendant drop of ferrofluid in a horizontal magnetic field. The initial drop size is chosen just below the breakup threshold under gravity. As the magnetic field is increased, the drop tilts in order to align with the direction of the total volume force that is exerted on it: weight plus magnetic force. The breakup is controlled by a generalized Bond number based on this total force and on the radius of the neck of the drop. The evolution of drop shape turns out to be a complex process governed by many parameters such as the angle between the total force and the needle, the drop size relative to the needle radius, and the wettability of the liquid on the needle material. This suggests a certain universality, that a single value of the critical Bond number is found regardless of magnetic fluid properties and whether the force is inclined or not. PMID:23944556

Havard, N; Risso, F; Tordjeman, Ph

2013-07-01

28

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

Science.gov (United States)

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. PMID:23671054

Lin, Nai-Ti; Xie, Chen-Yu; Huang, Shou-Ling; Chen, Chung-Hsuan; Luh, Tien-Yau

2013-07-01

29

Remote Neural Pendants In A Welding-Control System  

Science.gov (United States)

Neural network integrated circuits enhance functionalities of both remote terminals (called "pendants") and communication links, without necessitating installation of additional wires in links. Makes possible to incorporate many features into pendant, including real-time display of critical welding parameters and other process information, capability for communication between technician at pendant and host computer or technician elsewhere in system, and switches and potentiometers through which technician at pendant exerts remote control over such critical aspects of welding process as current, voltage, rate of travel, flow of gas, starting, and stopping. Other potential manufacturing applications include control of spray coating and of curing of composite materials. Potential nonmanufacturing uses include remote control of heating, air conditioning, and lighting in electrically noisy and otherwise hostile environments.

Venable, Richard A.; Bucher, Joseph H.

1995-01-01

30

Novel Chemically Amplified Imaging Materials Containing Malonate Pendant Groups.  

Science.gov (United States)

A new chemically amplified polymeric imaging system based on polymers containing t-butylmalonate pendant groups has been demonstrated. Both the homopolymer of di-t-butyl (vinylbenzyl)benzylmalonate and its copolymer with styrene have been tested in coatin...

J. M. Havard J. M. Frechet K. J. Wynne

1996-01-01

31

Protonation Studies of a Tungsten Dinitrogen Complex Supported by a Diphosphine Ligand Containing a Pendant Amine  

Energy Technology Data Exchange (ETDEWEB)

Treatment of trans-[W(N2)2(dppe)(PEtNMePEt)] (dppe = Ph2PCH2CH2PPh2; PEtNMePEt = Et2PCH2N(Me)CH2PEt2) with three equivalents of tetrafluoroboric acid (HBF4?Et2O) at -78 °C generated the seven-coordinate tungsten hydride trans-[W(N2)2(H)(dppe)(PEtNMePEt)][BF4]. Depending on the temperature of the reaction, protonation of a pendant amine is also observed, affording trans-[W(N2)2(H)(dppe)(PEtNMe(H)PEt)][BF4]2, with formation of the hydrazido complex, [W(NNH2)(dppe)(PEtNMe(H)PEt)][BF4]2, as a minor product. Similar product mixtures were obtained using triflic acid (HOTf). Upon acid addition to the carbonyl analogue, cis-[W(CO)2(dppe)(PEtNMePEt)], the seven-coordinate carbonyl-hydride complex, trans-[W(CO)2(H)(dppe)(PEtN(H)MePEt)][OTf]2 was generated. The mixed diphosphine complex without the pendant amine in the ligand backbone, trans-[W(N2)2(dppe)(depp)] (depp = Et2P(CH2)3PEt2), was synthesized and treated with HBF4?Et2O, selectively generating a hydrazido complex, [W(NNH2)(F)(dppe)(depp)][BF4]. Computational analysis was used to probe proton affinity of three sites of protonation, the metal, pendant amine, and N2 ligand in these complexes. Room temperature reactions with 100 equivalents of HOTf produced NH4+ from reduction of the N2 ligand (electrons come from W). The addition of 100 equivalents HOTf to trans-[W(N2)2(dppe)(PEtNMePEt)] afforded 0.88 ± 0.02 equivalents NH4+, while 0.36 ± 0.02 equivalents of NH4+was formed upon treatment of trans-[W(N2)2(dppe)(depp)], the complex without the pendant amine. 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. Computational resources were provided by the National Energy Research Scientific Computing Center (NERSC) at Lawrence Berkeley National Laboratory. Pacific Northwest National Laboratory is operated by Battelle for DOE.

Weiss, Charles J.; Egbert, Jonathan D.; Chen, Shentan; Helm, Monte L.; Bullock, R. Morris; Mock, Michael T.

2014-05-12

32

Pendant-Drop Surface-Tension Measurement On Molten Metal  

Science.gov (United States)

Method of measuring surface tension of molten metal based on pendant-drop method implemented in quasi-containerless manner and augmented with digital processing of image data. Electrons bombard lower end of sample rod in vacuum, generating hanging drop of molten metal. Surface tension of drop computed from its shape. Technique minimizes effects of contamination.

Man, Kin Fung; Thiessen, David

1996-01-01

33

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

International Nuclear Information System (INIS)

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

34

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

35

Extreme Ultraviolet Resist Fabricated Using Water Wheel-Like Cyclic Oligomer with Pendant Adamantyl Ester Groups  

Science.gov (United States)

The synthesis and properties of water wheel-like cyclic oligomer (noria\\text{PY) derivatives (noria\\text{PY-ADs) with pendant adamantyl ester (AD) groups were examined for their application as extreme ultraviolet (EUV) resist materials. Noria\\text{PY-ADs with various degrees of introduction (DI values) of AD groups were synthesized by adjusting the reactant feed ratios and reaction concentration. Solubility, film-forming property, and thermal stability were consistent with differences in DI values. The patterning properties of noria\\text{PY-AD25 (DI= 25%) were examined in an EUV resist system, and noria\\text{PY-AD25 provided a clear line-and-space pattern with 30 nm resolution and a line width roughness (LWR) of 11.3 nm.

Seki, Hiroyuki; Kudo, Hiroto; Oizumi, Hiroaki; Itani, Toshiro; Nishikubo, Tadatomi

2011-12-01

36

A water-soluble polycarbonate with dimethylamino pendant groups prepared by enzyme-catalyzed ring-opening polymerization.  

Science.gov (United States)

A water-soluble polycarbonate with dimethylamino pendant groups, poly(2-dimethylaminotrimethylene carbonate) (PDMATC), is synthesized and characterized. First, the six-membered carbonate monomer, 2-dimethylaminotrimethylene carbonate (DMATC), is prepared via the cyclization reaction of 2-(dimethylamino)propane-1,3-diol with triphosgene in the presence of triethylamine. Although the attempted ring-opening polymerization (ROP) of DMATC with Sn(Oct)(2) as a catalyst fails, the ROP of DMATC is successfully carried out with Novozym-435 as a catalyst to give water-soluble aliphatic polycarbonate PDMATC with low cytotoxicity and good degradability. PMID:22354753

Zhang, Xiaojin; Cai, Mengmeng; Zhong, Zhenlin; Zhuo, Renxi

2012-04-23

37

Maximum Stable Sets and Pendant Vertices in Trees  

CERN Document Server

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

38

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, based on the Dilthey reaction, could be carried up to sixth generation which contains 2776 benzene rings and possesses a diameter in the 27 nm range ("exploded dendrimer"). Monodispersity and dimen...

Andreitchenko, Ekaterina Vladimirovna

2006-01-01

39

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 measuri...

Arashiro, Emerson Y.; Demarquette, Nicole R.

1999-01-01

40

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-(methacryloyloxyethylureido cellobiose (MOU-Cel macromer was synthesized by coupling cellobiosylamine with 2-(methacryloyloxyethyl 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

2009-08-01

 
 
 
 
41

Incorporation of Cyclotriphosphazene as Pendant Groups to the Sago Network  

International Nuclear Information System (INIS)

Cyclotriphosphazene-incorporated sago wastes as pendant groups have been prepared and structurally characterized using FT-IR and SEM. The chemically modified sago wastes composite was applied with binders and developed as sound absorbing panels. These panels are a class of organic-inorganic based materials that exhibit excellent fire retardant properties. Sound absorbance test has given a higher value at 250, 500 and 2000 Hz, which indicates the suitability of the panel for used in medium frequency. The panel was 51 % lighter compared to fiber board. The function and basic manufacturing of sound absorbers products was aligned with the present products in the market. (author)

2012-12-01

42

Gelation of Copolymers Photo-crosslinked by Pendant Benzophenones  

Science.gov (United States)

Copolymers containing pendant benzophenone (BP) groups provide a simple and powerful route to crosslinkable polymer films. While the solution state photo-chemistry of BP is well established, and crosslinking of polymers blended with BP has been studied in detail, the process of crosslinking by covalently attached BP has received comparatively little attention. We have prepared copolymers of BP with several different monomers, and studied gelation as a function of BP content and degree of photochemical conversion. We seek to understand the influence of polymer chemistry on crosslinking efficiency, to guide choices of materials for photo- crosslinkable polymer films and to provide a route for tailoring morphology in polymer blends.

Christensen, Scott; Hayward, Ryan C.

2011-03-01

43

A Quasi-Containerless Pendant Drop Method for Surface Tension Measurements of Molten Metals and Alloys  

Science.gov (United States)

A quasi-containerless pendant drop method for measuring the surface tension of molten metals and alloys is being developed. The technique involves melting the end of a high-purity metal rod by bombardment with an electron beam to form a pendant drop under ultra-high vacuum conditions to minimize surface contamination.

Thiessen, David B.; Man, Kin F.

1994-01-01

44

Frequency Synthesizer.  

Science.gov (United States)

Dual phase lock loops are used to provide a rapid switching, low power, low spurious and fine resolution frequency synthesizer for various radio applications. The first phase lock loop provides for coarse frequency adjustment, and the second phase lock lo...

E. J. Nossen

1978-01-01

45

Mechanical characterization of the Varian Exact-arm and R-arm support systems for eight aS500 electronic portal imaging devices  

International Nuclear Information System (INIS)

Purpose: The aim of this study is to compare the positioning accuracy at different gantry angles of two electronic portal imaging devices (EPIDs) support arm systems by using EPID difference images as a measure for displacement. This work presents a comparison of the mechanical performance of eight Varian aS500 (Varian Medical Systems, Palo Alto, CA) EPIDs, mounted using either the Varian Exact-arm or R-arm. Methods: The mechanical performance of the two arm systems was compared by investigating the variation in sensitivity with gantry angle, both before and after the EPID position was adjusted after gantry rotation. Positional errors were investigated by subtracting images from a reference image taken at gantry 0 deg., and the amplitude of the peaks and troughs at the field edges for longitudinal (radial) and lateral (transverse) profiles across the resulting image was related to the distance of displacement. Calibration curves based on a pixel-by-pixel shift were generated for each EPID and the Varian hand pendant accuracy was compared to the calibration data. Results: The response of the EPIDs was found to change with gantry rotation, with the largest difference at 180 deg. The Exact-arm was found to correct well for any displacement, while the R-arm tended to overcorrect following repositioning using the hand pendant. The calibration curves were consistent within each set of matched linacs, and the hand pendant accuracy was similar for both arm systems, although generally in different directions. With respect to gantry rotation effects, the mechanical performance of the Exact-arm systems was found to be much better than that of the R-arm systems. At gantry positions 90 deg., 270 deg., and 180 deg. the average misalignment in the longitudinal direction was +4.2±0.2, +1.8±1.6, and +7.4±0.5 mm for the R-arms, and +2.9±0.2, +2.1±0.8, and +4.9±0.7 mm for the Exact-arms. In the lateral direction the average positional errors were +2.1±0.4, -4.7±0.4, and -2.5±0.5 mm for the R-arms, and -0.3±0.3, -0.5±0.3, and -0.4±0.2 mm for the Exact-arms. The hand pendant correction had minimal impact in the lateral direction for both arm systems. However in the longitudinal direction the mean errors for the R-arms were +3.4±0.7, +1.5±0.6, and +4.6±0.7 mm at gantry angles 90 deg., 270 deg., and 180 deg., and the equivalent Exact-arm errors were +0.9±0.3, +1.2±0.3, and +1.9±0.9 mm, respectively. Conclusions: The performance of the EPIDs demonstrate that the Exact-arm system provides a more reproducible position and better agreement with the EPID position as indicated on the EPID pendant at all gantry angles than the R-arm.

2010-04-01

46

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

2009-03-01

47

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

48

Multicolor electrochromic performance of electroactive poly(amic acid) containing pendant oligoaniline, azobenzene and sulfonic acid groups  

International Nuclear Information System (INIS)

A novel electroactive poly(amic acid) (EDA-CON-EPAA) containing oligoaniline pendants, azobenzene and sulfonic acid groups was synthesized by copolymerization. The synergistic interplay of these three distinct functional groups results in a number of interesting and novel properties. The polymer showed photoisomerization induce by irradiation with ultraviolet light and visible light by virtue of azobenzene groups, and also revealed excellent electroactivity in acid, neutral and even in alkaline solutions (pH = 12) due to self-doping between oligoaniline and sulfonic acid (and/or carboxylic acid) groups. Moreover, EDA-CON-EPAA displayed acceptable electrochromic performance even in alkaline solutions and multiple colors attributed to the complementary effects of the two chromophores, which greatly enlarged the range of the electrochromic application. The coloration efficiency could still reach 93.8 cm2/C (at 700 nm) even at pH = 10

2013-02-01

49

Arm CT scan  

Science.gov (United States)

CAT scan - arm; Computed axial tomography scan - arm; Computed tomography scan - arm; CT scan - arm ... together. You must be still during the exam. Movement can cause blurred images. You may be told ...

50

Arm ache.  

Science.gov (United States)

Both patients and providers hope for better management strategies for nonspecific activity-related upper limb pain (herein referred to as "arm ache"). The next innovation in the care of arm ache may arise from the strong evidence that mood, coping strategies (e.g., catastrophic thinking), and heightened illness concern-all very responsive to treatment with cognitive behavioral therapy-account for a large percentage of the variation in symptom intensity and magnitude of disability. This focus on treatments to reduce symptoms and disability represents a change in culture for patients and providers, both of whom are accustomed to the biomedical framework that anticipates a direct correspondence between illness (the state of being unwell) and disease (pathophysiology). Not all patients are ready for such an approach, but as a first step health providers can prioritize empathy; remain mindful that words, illness concepts, and treatments can reinforce ineffective coping strategies; and encourage curiosity about the human illness experience. PMID:24839415

Chabok, Hosein Ahmadzadeh; Ring, David

2014-06-01

51

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

52

Synthesizing Chaos  

Science.gov (United States)

Chaos is usually attributed only to nonlinear systems. Yet it was recently shown that chaotic waveforms can be synthesized by linear superposition of randomly polarized basis functions. The basis function contains a growing oscillation that terminates in a large pulse. We show that this function is easily realized when viewed backward in time as a pulse followed by ringing decay. Consequently, a linear filter driven by random pulses outputs a waveform that, when viewed backward in time, exhibits essential qualities of chaos, i.e. determinism and a positive Lyapunov exponent. This phenomenon suggests that chaos may be connected to physical theories whose framework is not that of a deterministic dynamical system. We demonstrate that synthesizing chaos requires a balance between the topological entropy of the random source and the dissipation in the filter. Surprisingly, using different encodings of the random source, the same filter can produce both Lorenz-like and R"ossler-like waveforms. The different encodings can be viewed as grammar restrictions on a more general encoding that produces a chaotic superset encompassing the Lorenz and R"ossler paradigms of nonlinear dynamics. Thus, the language of deterministic chaos provides a useful description for a class of signals not generated by a deterministic system.

Blakely, Jonathan; Corron, Ned; Hayes, Scott; Pethel, Shawn

2007-03-01

53

A new DRAM-type memory devices based on polymethacrylate containing pendant 2-methylbenzothiazole  

Energy Technology Data Exchange (ETDEWEB)

Graphical abstract: The devices fabricated with 75 nm and 45 nm thick pBVMA films were both found to exhibit DRAM type memory behaviors, which may indicate that the Al nanoparticles had no penetration into the thin film during the vacuum-deposition process. Highlights: Black-Right-Pointing-Pointer The side-functional moieties of pBVMA regularly arranged in film state. Black-Right-Pointing-Pointer The device exhibits volatile memory behavior with an ON/OFF current ratio up to 10{sup 5}. Black-Right-Pointing-Pointer The film thickness has nothing to do with the device's memory behavior. Black-Right-Pointing-Pointer Physical theoretical models and molecular simulation supported the memory mechanism. - Abstract: A polymethacrylate containing pendant 2-methylbenzothiazole (pBVMA) with good thermal stability was synthesized by free radical polymerization. The devices based on pBVMA possess a sandwich structure comprising bottom indium-tin oxide (ITO) electrode and top Al electrode. The as-fabricated device exhibits the dynamic random access memory (DRAM) behavior with an ON/OFF current ratio up to 10{sup 5} and can endure 10{sup 8} read cycles under -1 V pulse voltage. The effect of the film thickness on the device performance was investigated and the devices fabricated with 75 nm and 45 nm thick pBVMA films were both found to exhibit DRAM type memory behaviors, which may indicate that the Al nanoparticles had no penetration into the thin film during the vacuum-deposition process. The molecular simulation and physical theoretical models were analyzed and the mechanism of the DRAM performance may be attributed to the weak electron withdrawing ability of the molecule.

Wang Dong; Li Hua; Li Najun; Zhao Ying; Zhou Qianhao; Xu Qingfeng [Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 199 Ren' ai Road, Suzhou 215123 (China); Lu Jianmei, E-mail: lujm@suda.edu.cn [Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 199 Ren' ai Road, Suzhou 215123 (China); Wang Lihua [Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 199 Ren' ai Road, Suzhou 215123 (China)

2012-05-15

54

Concentration effects on peptide elution from pendant PEO layers.  

Science.gov (United States)

In earlier work, we have provided direction for development of responsive drug delivery systems based on modulation of structure and amphiphilicity of bioactive peptides entrapped within pendant polyethylene oxide (PEO) brush layers. Amphiphilicity promotes retention of the peptides within the hydrophobic inner region of the PEO brush layer. In this work, we describe the effects of peptide surface density on the conformational changes caused by peptide-peptide interactions, and show that this phenomenon substantially affects the rate and extent of peptide elution from PEO brush layers. Three cationic peptides were used in this study: the arginine-rich amphiphilic peptide WLBU2, the chemically identical but scrambled peptide S-WLBU2, and the non-amphiphilic homopolymer poly-l-arginine (PLR). Circular dichroism (CD) was used to evaluate surface density effects on the structure of these peptides at uncoated (hydrophobic) and PEO-coated silica nanoparticles. UV spectroscopy and a quartz crystal microbalance with dissipation monitoring (QCM-D) were used to quantify changes in the extent of peptide elution caused by those conformational changes. For amphiphilic peptides at sufficiently high surface density, peptide-peptide interactions result in conformational changes which compromise their resistance to elution. In contrast, elution of a non-amphiphilic peptide is substantially independent of its surface density, presumably due to the absence of peptide-peptide interactions. The results presented here provide a strategy to control the rate and extent of release of bioactive peptides from PEO layers, based on modulation of their amphiphilicity and surface density. PMID:24780434

Wu, Xiangming; Ryder, Matthew P; McGuire, Joseph; Schilke, Karl F

2014-06-01

55

Polymer resins with amino acid containing pendants for sorption of bilirubin. I. Comparison of Merrifield and polyamide resins.  

Science.gov (United States)

Merrifield resins with various amino acid containing pendants and a water swellable polyamide resin with the peptide alanine-alanine-alanine-arginine as the pendant group have been prepared by solid phase peptide synthesis. Merrifield resins with either arginine or lysine pendants are capable of sorbing bilirubin from aqueous solution (pH = 7.8) but those with other amino acid pendants gave no indication of sorption. The polyamide-arginine resin showed, on a functional group basis, a higher capacity for bilirubin than does cholestyramine. It is proposed that the formation of salt linkages causes a strong interaction of bilirubin with arginine and lysine. PMID:6490193

Henning, D S; Lajoie, G A; Brown, G R; St-Pierre, L E; St-Pierre, S

1984-07-01

56

Accurate surface tension measurement of glass melts by the pendant drop method  

Science.gov (United States)

A pendant drop tensiometer, coupled with image digitization technology and a best-fitting algorithm, was built to accurately measure the surface tension of glass melts at high temperatures. More than one thousand edge-coordinate points were obtained for a pendant glass drop. These edge points were fitted with the theoretical drop profiles derived from the Young-Laplace equation to determine the surface tension of glass melt. The uncertainty of the surface tension measurements was investigated. The measurement uncertainty (?) could be related to a newly defined factor of drop profile completeness (Fc): the larger the Fc is, the smaller ? is. Experimental data showed that the uncertainty of the surface tension measurement when using this pendant drop tensiometer could be +/-3 mN/m for glass melts.

Chang, Yao-Yuan; Wu, Ming-Ya; Hung, Yi-Lin; Lin, Shi-Yow

2011-05-01

57

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 bo...

1999-01-01

58

Synthesis of hydronaphthalenes through coupling of enyne carbonyl compounds that contain pendant alkene groups with Fischer carbene complexes  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The coupling of enyne carbonyl compounds that contain pendant alkene groups with Fischer carbene complexes to afford furans that contain pendant alkene groups is described. Subsequent intramolecular Diels-Alder reactions are effective in select cases, resulting in hydronaphthalene systems after dehydration. Although the Diels-Alder event is thermodynamically unfavorable, the overall transformation of alkene-furans to dihydronaphthalenes is a favorable process.

Kumar-patti, Rajesh; Duan, Shaofeng; Camacho-davila, Alejandro; Waynant, Kris; Dunn, Kenneth A.; Herndon, James W.

2010-01-01

59

Sensing System for Detection and Control of Deposition on Pendant Tubes in Recovery and Power Boilers.  

Science.gov (United States)

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 bo...

G. Kychakoff M. A. Afromowitz R. E. Hogle

2005-01-01

60

Self-rectifying electron beam melter for pendant-drop containerless processing  

Science.gov (United States)

A self-rectifying electron beam melting technique is described. Utilizing an ac power supply, in contrast to the more usual dc supply, the in situ self-rectifying approach offers a simple and very inexpensive means of producing metallic pendant drops for use in containerless melt-processing experiments.

Pyun, D. S.; Collings, E. W.

1993-01-01

 
 
 
 
61

Quenching of excited state of polymer-pendant Ru(bpy)_3"2"+ by methylviologen  

International Nuclear Information System (INIS)

Copolymer pendant tris(2,2'-bipyridine)ruthenium(II) (Ru(bpy)_3"2"+) complexes were prepared, and the quenchings of their excited state with methylviologen (MV"2"+) were studied. The quenching rate constant of the excited state of copolymer pendant Ru(bpy)_3"2"+ containing acrylic acid showed a novel pH effect in water which depends on the dissociation of the acrylic acid to acrylate. The dissociated acrylic acid forms an anionic microdomain around the pendant Ru complex, and attracts the positively charged MV"2"+, thus enhancing the apparent rate of the quenching by 10 to 30 times. The copolymer pendant Ru complex containing acrylic acid showed quenching behavior in methyl alcohol entirely different from that in aqueous system depending on the additives such as acid, alkaline, or neutral salt. The non-linear Stern-Volmer plots indicate the presence of static quenching in methyl alcohol. Quenching models consisting of both dynamic and static mechanisms are proposed and discussed. (author)

1984-12-01

62

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

63

Structural and spectral investigation on the Co II complexes with 1,4-diazacycloheptane (DACH) functionalized by heterocyclic pendants  

Science.gov (United States)

A series of penta-coordinated Co II complexes of 1,4-diazacycloheptane (DACH) functionalized by additional imidazole or pyridine donor pendants, [Co L1Cl](ClO 4)·H 2O ( 1), [Co L2Cl](ClO 4) ( 2) and [Co L3Cl](ClO 4)·CH 3OH ( 3), where L1=1,4-bis(imidazole-4-ylmethyl)-DACH, L2=1,4-bis( N-1-methylimidazol-2-ylmethyl)-DACH and L3=1,4-bis(pyridyl-2-ylmethyl)-DACH have been synthesized and characterized by elemental analyses, IR and UV-Vis spectra. In all the mononuclear complexes, each Co II center is penta-coordinated to four nitrogen donors of the ligand and one axial chloride anion. The crystal structure of complex 2 has been determined by X-ray diffraction analysis, which forms a one-dimensional linear structure through inter-molecular C-H⋯Cl and C-H⋯O hydrogen-bonding.

Guo, Ya-Mei; Du, Miao; Bu, Xian-He

2002-06-01

64

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

2013-04-01

65

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

66

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

67

Determination of cerium ion by polymeric membrane and coated graphite electrode based on novel pendant armed macrocycle  

Energy Technology Data Exchange (ETDEWEB)

Plasticized membranes using 2,3,4:12,13,14-dipyridine-1,3,5,8,11,13,15,18-octaazacycloicosa-2,12-diene (L{sub 1}) and 2,3,4:12,13,14-dipyridine-1,5,8,11,15,18-hexamethylacrylate- 1,3,5,8,11,13,15,18-octaazacycloicosa-2,12-diene (L{sub 2}) have been prepared and explored as Ce(III) selective sensors. Effect of various plasticizers viz. dibutylphthalate (DBP), tri-n-butylphthalate (TBP), o-nitrophenyloctylether (o-NPOE), dioctylphthalate (DOP), benzylacetate (BA) and anion excluders, sodium tetraphenylborate (NaTPB) and potassium tetrakis p-(chlorophenyl) borate was studied in detail and improved performance was observed. Optimum performance was observed for the membrane sensor having a composition of L{sub 2}:PVC:o-NPOE:KTpClPB in the ratio of 6:34:58:2 (w/w, mg). The performance of the membrane based on L{sub 2} was compared with polymeric membrane electrode (PME) as well as with coated graphite electrode (CGE). The electrodes exhibit Nernstian slope for Ce(III) ions with limits of detection of 8.3 x 10{sup -8} mol L{sup -1} for PME and 7.7 x 10{sup -9} mol L{sup -1} for CGE. The response time for PME and CGE was found to be 12 s and 10 s respectively. The potentiometric responses are independent of the pH of the test solution in the pH range 3.5-7.5 for PME and 2.5-8.5 for CGE. The CGE could be used for a period of 5 months. The practical utility of the CGE has been demonstrated by its usage as an indicator electrode in potentiometric titration of oxalate and fluoride ions with Ce(III) solution. The proposed electrode was also successfully applied to the determination of fluoride ions in mouthwash solution and oxalate ions in real samples.

Singh, Ashok K., E-mail: akscyfcy@iitr.ernet.in [Department of Chemistry, Indian Institute of Technology-Roorkee, Roorkee 247 667 (India); Singh, Prerna [Department of Chemistry, Indian Institute of Technology-Roorkee, Roorkee 247 667 (India)

2010-08-24

68

Determination of cerium ion by polymeric membrane and coated graphite electrode based on novel pendant armed macrocycle.  

Science.gov (United States)

Plasticized membranes using 2,3,4:12,13,14-dipyridine-1,3,5,8,11,13,15,18-octaazacycloicosa-2,12-diene (L(1)) and 2,3,4:12,13,14-dipyridine-1,5,8,11,15,18-hexamethylacrylate-1,3,5,8,11,13,15,18-octaazacycloicosa-2,12-diene (L(2)) have been prepared and explored as Ce(III) selective sensors. Effect of various plasticizers viz. dibutylphthalate (DBP), tri-n-butylphthalate (TBP), o-nitrophenyloctylether (o-NPOE), dioctylphthalate (DOP), benzylacetate (BA) and anion excluders, sodium tetraphenylborate (NaTPB) and potassium tetrakis p-(chlorophenyl) borate was studied in detail and improved performance was observed. Optimum performance was observed for the membrane sensor having a composition of L(2):PVC:o-NPOE:KTpClPB in the ratio of 6:34:58:2 (w/w, mg). The performance of the membrane based on L(2) was compared with polymeric membrane electrode (PME) as well as with coated graphite electrode (CGE). The electrodes exhibit Nernstian slope for Ce(III) ions with limits of detection of 8.3x10(-8) mol L(-1) for PME and 7.7x10(-9) mol L(-1) for CGE. The response time for PME and CGE was found to be 12 s and 10 s respectively. The potentiometric responses are independent of the pH of the test solution in the pH range 3.5-7.5 for PME and 2.5-8.5 for CGE. The CGE could be used for a period of 5 months. The practical utility of the CGE has been demonstrated by its usage as an indicator electrode in potentiometric titration of oxalate and fluoride ions with Ce(III) solution. The proposed electrode was also successfully applied to the determination of fluoride ions in mouthwash solution and oxalate ions in real samples. PMID:20800729

Singh, Ashok K; Singh, Prerna

2010-08-24

69

Determination of cerium ion by polymeric membrane and coated graphite electrode based on novel pendant armed macrocycle  

International Nuclear Information System (INIS)

Plasticized membranes using 2,3,4:12,13,14-dipyridine-1,3,5,8,11,13,15,18-octaazacycloicosa-2,12-diene (L1) and 2,3,4:12,13,14-dipyridine-1,5,8,11,15,18-hexamethylacrylate- 1,3,5,8,11,13,15,18-octaazacycloicosa-2,12-diene (L2) have been prepared and explored as Ce(III) selective sensors. Effect of various plasticizers viz. dibutylphthalate (DBP), tri-n-butylphthalate (TBP), o-nitrophenyloctylether (o-NPOE), dioctylphthalate (DOP), benzylacetate (BA) and anion excluders, sodium tetraphenylborate (NaTPB) and potassium tetrakis p-(chlorophenyl) borate was studied in detail and improved performance was observed. Optimum performance was observed for the membrane sensor having a composition of L2:PVC:o-NPOE:KTpClPB in the ratio of 6:34:58:2 (w/w, mg). The performance of the membrane based on L2 was compared with polymeric membrane electrode (PME) as well as with coated graphite electrode (CGE). The electrodes exhibit Nernstian slope for Ce(III) ions with limits of detection of 8.3 x 10-8 mol L-1 for PME and 7.7 x 10-9 mol L-1 for CGE. The response time for PME and CGE was found to be 12 s and 10 s respectively. The potentiometric responses are independent of the pH of the test solution in the pH range 3.5-7.5 for PME and 2.5-8.5 for CGE. The CGE could be used for a period of 5 months. The practical utility of the CGE has been demonstrated by its usage as an indicator electrode in potentiometric titration of oxalate and fluoride ions with Ce(III) solution. The proposed electrode was also successfully applied to the determination of fluoride ions in mouthwash solution and oxalate ions in real samples.

2010-08-24

70

Equilibrium and kinetic properties of the DO3A derivative ligand functionalized by ethyl-amine pendant arm  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A munkám során a DO3A-AE3- ligandum protonálódási állandóit, komplexképz? sajátságait, Ln3+-komplexek képz?dési és disszociációs kinetikáját vizsgáltam pH-potenciometriás és UV-VIS spektrofotmetriás módszerek segítségével. A H3DO3A-AE ligandum protonálódási állandóit pH-potenciometriás titrálásának eredményeib?l számítottuk ki. A H3DO3A-AE, a H3DOTA-EN, a H3DO3A és H4DOTA ligandumok protonálódási állandóinak összehasonlítása alapján megállap?...

2013-01-01

71

Professional embedded ARM development  

CERN Document Server

A practical Wrox guide to ARM programming for mobile devices With more than 90 percent of mobile phones sold in recent years using ARM-based processors, developers are eager to master this embedded technology. If you know the basics of C programming, this guide will ease you into the world of embedded ARM technology. With clear explanations of the systems common to all ARM processors and step-by-step instructions for creating an embedded application, it prepares you for this popular specialty. While ARM technology is not new, existing books on the topic predate the current explosive growth

Langbridge, James A

2013-01-01

72

Arms Control Treaties  

Science.gov (United States)

Brief summaries of all the nuclear arms control treaties: Antarctic Treaty, Hot Line Agreement, Limited Test Ban Treaty, Outer Space Treaty, Latin America Nuclear Free Zone Treaty, Nuclear Non-Proliferation Treaty, Seabed Treaty, Strategic Arms Limitation Treaty I (Interim Agreement), Anti-Ballistic Missile Treaty, Threshold Test Ban Treaty, Peaceful Nuclear Explosions Treaty, Environmental Modification Convention, Strategic Arms Limitation Treaty II Treaty, South Pacific Nuclear Free Zone Treaty, Intermediate-Range Nuclear Forces Treaty - INF, Ballistic Missile Launch Notification Agreement, Strategic Arms Reduction Treaty, Strategic Arms Reduction Treaty II, Treaty of Pelindaba, Comprehensive Test Ban Treaty, Strategic Offensive Reductions Treaty

73

Comparison of the interfacial activity between homogeneous and Janus gold nanoparticles by pendant drop tensiometry.  

Science.gov (United States)

The interfacial activity of 3.5 nm homogeneous (HPs) and amphiphilic Janus gold nanoparticles (JPs) was characterized by pendant drop tensiometry for water/air and water/decane interfaces. This technique requires a smaller quantity of nanoparticles than the traditional Langmuir balance technique. The direct deposition at the interface of the nanoparticles dispersed in a spreading solvent also requires smaller quantities of sample than does adsorption from the bulk. From the growing and shrinking of the pendant drops, the interfacial activity of the nanoparticles can be evaluated and compared within a wide range of area per particle. In this work, the JPs exhibited a higher interfacial activity than did the HPs in all cases. A hard disk model fits the piecewise compression isotherm of the HPs, yet this model underestimates the interactions between the JPs adsorbed at the interface. PMID:24490655

Fernandez-Rodriguez, Miguel Angel; Song, Yang; Rodríguez-Valverde, Miguel Ángel; Chen, Shaowei; Cabrerizo-Vilchez, Miguel Angel; Hidalgo-Alvarez, Roque

2014-02-25

74

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 atta...

2010-01-01

75

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

76

The Intersection of All Maximum Stable Sets of a Tree and its Pendant Vertices  

CERN Document Server

A stable set in a graph G is a set of mutually non-adjacent vertices, alpha(G) is the size of a maximum stable set of G, and core(G) is the intersection of all its maximum stable sets. In this paper we demonstrate that in a tree T, of order n greater than 1, any stable set of size greater or equal to n/2 contains at least one pendant vertex. Hence, we deduce that any maximum stable set in a tree contains at least one pendant vertex. Our main finding is the theorem claiming that if T does not own a perfect matching, then at least two pendant vertices an even distance apart belong to core(T). While it is proved by Levit and Mandrescu that if G is a connected bipartite graph of order at least 2, then the size of core(G) is different from 1, our new statement reveals an additional structure of the intersection of all maximum stable sets of a tree. The above assertions give refining of one result of Hammer, Hansen and Simeone, stating that if a graph G is of order less than 2*alpha(G), then core(G) is non-empty, a...

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

2000-01-01

77

Distortions of a flexible metal-organic framework from substituted pendant ligands.  

Science.gov (United States)

Four new variants of the 1,4-benzenedicarboxylate MIL-53 structure have been prepared for Co(II) under solvothermal conditions and their structures solved and refined from single-crystal X-ray data. All materials contain pendant pyridine-N-oxide ligands that bridge pairs of Co(II) atoms in the inorganic backbone of the structure via O. By the use of the ligands 3-bromopyridine-N-oxide, 4-methoxypyridine-N-oxide, isoquinoline-N-oxide and 4-phenylpyridine-N-oxide, materials are prepared with the same topology but distinct structures. These illustrate how the MIL-53 structure is able to distort to accommodate the bulk of the various substituents on the pyridine ring. The bulkiest pendant ligand, 4-phenylpyridine-N-oxide, results in a distortion of the diamond-shaped channels in an opposite sense to that seen previously in expanded forms of the parent MIL-53 structure. By comparison with published crystal structures for MIL-53 with various occluded guests, the structural distortions that take place to accommodate the pendant ligands are quantified and it is shown how a twisting of the 1,4-benzenedicarboxylate ligand, instead of a hinging about the ?(2)-carboxylate-metal connection, allows the new structures that are observed. PMID:24441123

Munn, Alexis S; Clarkson, Guy J; Walton, Richard I

2014-02-01

78

Regional Arms Control Arrangements for Developing Areas. Arms and Arms Control in Latin America, the Middle East, and Africa.  

Science.gov (United States)

Contents: Arms control in Latin America; Arms control in the Middle East; Arms control in North Africa; Arms control in sub-Saharan Africa; International regional organizations and regional arms control relationships between regional arms control agreemen...

1964-01-01

79

Controlled radical polymerization and quantification of solid state electrical conductivities of macromolecules bearing pendant stable radical groups.  

Science.gov (United States)

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, because of 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 (?1×10(-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. PMID:24044350

Rostro, Lizbeth; Baradwaj, Aditya G; Boudouris, Bryan W

2013-10-23

80

Modelling of bionic arm  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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.

2010-01-01

 
 
 
 
81

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

2010-04-01

82

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

83

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

84

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

85

Analysis of the polar crane pendant cable from Three Mile Island - Unit 2  

International Nuclear Information System (INIS)

The pendant cable to the polar crane in Three Mile Island - Unit 2 (TMI-2) was suspended near the center of the containment during the March 1979 accident. It sustained considerable thermal damage from the hydrogen burn that occurred. The cable was removed from TMI-2 and cut into sections, which were then analyzed to assess the extent of damage and learn as much as possible about the accident environment (by studying its effect on the cable). Both electrical and materials tests were employed in the analyses, which produced information about the hydrogen burn and contamination levels in containment. 10 refs., 24 figs

1986-01-01

86

Synthesis, Characterization and Reactivity of Fe Complexes Containing Cyclic Diazadiphosphine Ligands: The Role of the Pendant Base in Heterolytic Cleavage of H2  

Energy Technology Data Exchange (ETDEWEB)

The iron complexes CpFe(PPh2NBn2)Cl (1-Cl), CpFe(PPh2NPh2)Cl (2-Cl), CpFe(PPh2C5)Cl (3-Cl) (where PPh2NBn2 is 1,5-dibenzyl-1,5-diaza-3,7-diphenyl-3,7-diphosphacyclooctane, PPh2NPh2 is 1,3,5,7-tetraphenyl-1,5-diaza-3,7-diphosphacyclooctane, and PPh2C5 is 1,4-diphenyl-1,4-diphosphacycloheptane) have been synthesized and characterized by NMR spectroscopy, electrochemical studies, and X-ray diffraction studies. These chloride derivatives are readily converted to the corresponding hydride complexes CpFe(PPh2NBn2)H (1-H), CpFe(PPh2NPh2)H (2-H), CpFe(PPh2C5)H (3-H)] and H2 complexes [CpFe(PPh2NBn2)(H2)]BArF4, [1-H2]BArF4, (where BArF4 is B[(3,5-(CF3)2C6H3)4]?), [CpFe(PPh2NPh2)(H2)]BArF4, [2-H2]BArF4, and [CpFe(PPh2C5)(H2)]BArF4, [3-H2]BArF4 as well as [CpFe(PPh2NBn2)(CO)]BArF4, [1-CO]BArF4. Structural studies are reported for [1-H2]BArF4, 1-H, 2-H, and [1-CO]BArF4. The conformations adopted by the chelate rings of the PPh2NBn2 ligand in the different complexes are determined by attractive or repulsive interactions between the sixth ligand of these pseudo-octahedral complexes and the pendant N atom of the ring adjacent to the sixth ligand. An example of an attractive interaction is the observation that the distance between the N atom of the pendant amine and the C atom of the coordinated CO ligand for [1-CO]BArF4 is 2.848 Å, considerably shorter than the sum of the van der Waals radii of N and C atoms. Experimental and theoretical studies of H/D exchange by the complexes [1-H2]+, [2-H2]+, and [3-H2]+ indicate that the relatively rapid exchange observed for [1-H2]+ and [2-H2]+ compared to [3-H2]+ is consistent with intramolecular heterolytic cleavage of H2 mediated by the pendant amine. These mononuclear FeII dihydrogen complexes containing pendant amines in the ligands mimic crucial features of the distal Fe site of the active site of the [FeFe] hydrogenase required for H-H bond formation and cleavage. We thank the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences, Biosciences and Geosciences, for support of this research. S.C. (DFT computations) and M. J. O. (NMR experiments) were supported by 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, under FWP 56073. Pacific Northwest National Laboratory is operated by Battelle for the U.S. Department of Energy.

Liu, Tianbiao L.; Chen, Shentan; O' Hagan, Molly J.; Rakowski DuBois, Mary; Bullock, R. Morris; DuBois, Daniel L.

2012-04-11

87

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

88

Inorganic syntheses, v.48  

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.

Shreeve, Jean'ne M

2009-01-01

89

Inorganic syntheses, v.40  

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.

Busch, Daryle H

2009-01-01

90

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

91

Modeling a VST Synthesizer  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Our main purpose of this project is to experiment and program a VST synthesizer plug-in which can be used to model and create sounds through a host application in a computer. In this report, we firstly present the history of the synthesizers. Secondly, we explain and discuss the requirements and “must-know” parts of a typical synthesizer. We then compare the analogue synthesis and digital synthesis and explain the differences between them. After that, the two leading p...

Karavasileiadis, Christos; O Bryan, Stephan

2008-01-01

92

Les inhibiteurs spécifiques du recaptage de la sérotonine pendant la grossesse et l’issue du nourrisson  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Il est très important de bien soigner la dépression pendant la grossesse pour la santé de la mère, du fœtus, puis du nouveau-né. Les inhibiteurs sélectifs du recaptage de la sérotonine (ISRS) sont souvent utilisés comme antidépresseurs. D’après une étude américaine, 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’accroître le risque de malformations congé...

Jefferies, Ann L.

2011-01-01

93

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

94

Phoenix's Robotic Arm  

Science.gov (United States)

This is a lesson about programming and communications in space exploration. Learners will simulate sending commands to operate a robotic arm to complete a task. This is lesson 13 of 16 in the MarsBots learning module.

95

Arms Control in the 21st Century.  

Science.gov (United States)

The tropical Areas covered in 'Arms Control of the 21st Century' were: Strategic Offensive Arms Control, Strategic Defensive Arms Control, Conventional Arms Control and, Regional Arms Control. In addressing these issue areas, the working groups focused on...

1996-01-01

96

Armed conflict and child health.  

Science.gov (United States)

Armed conflict has a major impact on child health throughout the world. One in six children worldwide lives in an area of armed conflict and civilians are more likely to die than soldiers as a result of the conflict. In stark contrast to the effect on children, the international arms trade results in huge profits for the large corporations involved in producing arms, weapons and munitions. Armed conflict is not inevitable but is an important health issue that should be prevented. PMID:21393303

Rieder, Michael; Choonara, Imti

2012-01-01

97

Development of electrochemical sensors for nano scale Tb(III) ion determination based on pendant macrocyclic ligands  

International Nuclear Information System (INIS)

The two macrocyclic pendant ligands 3,4,5:12,13,14-dipyridine-2,6,11, 15-tetramethyl-1,7,10,16-tetramethylacrylate -1,4,7,10,13, 16-hexaazacyclooctadeca-3,13-di ene (L1) and 3,4,5:12,13,14-dipyridine-2,6,11,15-tetramethyl-1,7,10,16-tetra(2-cyano ethane)-1,4,7,10,13,16-hexaazacyclooctadeca-3,13-diene (L2) have been synthesized and explored as neutral ionophores for preparing poly(vinylchloride) (PVC) based membrane sensors selective to Tb(III) ions. Effects of various plasticizers and anion excluders were studied in detail and improved performance was observed. The best performance was obtained for the membrane sensor having a composition of L1: PVC:1-CN:NaTPB in the ratio of 6: 32: 58: 4 (w/w; mg). The performance of the membrane based on L1 was compared with polymeric membrane electrode (PME) as well as with coated graphite electrode (CGE). The electrodes exhibit Nernstian slope for Tb3+ ions with limits of detection of 3.4 x 10-8 mol L-1 for PME and 5.7 x 10-9 mol L-1 for CGE. The response time for PME and CGE was found to be 10 s and 8 s, respectively. The potentiometric responses are independent of the pH of the test solution in the pH range 3.0-7.5 for PME and 2.0-8.5 for CGE. The CGE has found to work satisfactorily in partially non-aqueous media upto 30% (v/v) content of methanol, ethanol and 20% (v/v) content of acetonitrile and could be used for a period of 5 months. The CGE was used as indicator electrode in the potentiometric titration of Tb3+ ions with EDTA and in determination of fluoride ions in various samples. It can also be used in direct determination of Tb3+ ions in tap water and various binary mixtures with quantitative results

2009-02-02

98

Synthesizing an Alkaloid  

Science.gov (United States)

In this video segment, adapted from NOVA, learn how chemist Percy Julian revolutionized chemistry by synthesizing the alkaloid physostigminefrom scratch—the first total synthesis of a chemical compound.

Foundation, Wgbh E.

2007-02-12

99

Inorganic Syntheses, 35  

CERN Document Server

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

100

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.

2005-07-01

 
 
 
 
101

High-efficiency bipolar electroluminescent polymer containing an oxadiazole pendant group  

Energy Technology Data Exchange (ETDEWEB)

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 {approx} 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.

Kim, Jin Young; Park, Sung Heum; Lee, Kwang Hee; Jin, Sung Ho [Pusan National University, Busan (Korea, Republic of)

2005-07-15

102

Proton and Electron Additions to Iron (II) Dinitrogen Complexes Containing Pendant Amines  

Energy Technology Data Exchange (ETDEWEB)

We describe a single site cis-(H)FeII-N2 complex, generated by the protonation of an iron-carbon bond of a "reduced" iron complex, that models key aspects of proposed protonated intermediates of the E4 state of nitrogenase. The influence on N2 binding from the addition of protons to the pendant amine sites in the second coordination sphere is described. Furthermore, the addition of electrons to the protonated complexes results in H2 loss. The mechanism of H2 loss is explored to draw a parallel to the origin of H2 loss (homolytic or heterolytic) and the nature of N2 coordination in intermediates of the E4 state of nitrogenase.

Heiden, Zachariah M.; Chen, Shentan; Labios, Liezel AN; Bullock, R. Morris; Walter, Eric D.; Tyson, Elizabeth L.; Mock, Michael T.

2014-03-10

103

Efficient inverted bulk heterojunction photovoltaic devices using a transparent polymeric interfacial buffer layer with C60 pendant and UV curable groups.  

Science.gov (United States)

We demonstrate the synthesis of a transparent, polymeric n-type material (M1) consisting of C60 pendant and UV curable groups in side chains. This material (M1) is employed as a polymeric n-type interfacial buffer layer for an efficient inverted bulk heterojunction (BHJ) photovoltaic device based on regioregular poly(3-hexylthiophene):[6,6]-phenyl C61 butyric acid methyl ester (P3HT:PC61BM) active layer. Under simulated solar illumination of AM 1.5G (100 mW/cm2), the highest efficient devices fabricated with a configuration of ITO/interfacial buffer layer (M1,10 nm)/P3HT:PC61BM (1:0.9 w:w) (120 nm)/PEDOT:PSS (30 nm)/Ag (100 nm) achieve an average power conversion efficiency PCE of 2.16%, with short-circuit current J(SC) = 6.70 mA/cm2, fill factor FF = 54.2%, and open-circuit voltage V(OC) = 0.60 V. This result is comparable to the inverted BHJ photovoltaic devices fabricated with Cs2CO3, one of widely used as a buffer layer. The synthesized M1 have thus proven to be promising polymeric interfacial buffer layer for high efficient BHJ photovoltaic devices. PMID:22852380

Shin, Younghwan; Jeong, Seonju; Kwon, Hyeok Yong; Han, Yoon Soo; Kwon, Younghwan

2012-05-01

104

Reaction with glutathione. A possible mechanism involved in rodent brain retention of a 99mTc SNS/S complex containing a pendant ester functionality  

International Nuclear Information System (INIS)

The synthesis, characterization of MvO([CH3CH2N(CH2CH2S)2](p-S-Ph-COOCH2-CH3)) (M:99mTc: I, Re: II) is presented in this work, where a pendant ester function is attached to the monothiolate ligand. Chemical structure of I is established after chromatographic comparison with II, synthesized in macroscopic amounts. Complex II is fully characterized by classical methods of analysis showing that the compound adopts a distorted trigonal bipyramidal configuration around the metal. The two sulfur atoms of the tridentate ligand and the oxo group form the basal plane, while the remaining nitrogen atom of the tridentate ligand and the sulfur atom of the monothiolate ligand occupy the apices of the bipyramid. In vitro challenge experiments with glutathione (GSH) in neutral aqueous medium demonstrate, that I suffers nucleophilic attack by GSH and thereby transformation to a more hydrophilic daughter metal compound. Formation of the latter depends on time and GSH concentration. Tissue distribution in mice shows minor retention in brain. As rodent brain presents no esterases to hydrolyze the ester group of I, while the intracerebral content in GSH amounts to 2 mM, the above described mechanism is suspected for the observed brain retention. However, in primate brain cells retention of I may additionally involve the hydrolysis of the ester function to the corresponding acid, as already revealed by preliminary in vitro experiments using esterase incubates. (author)

1998-08-01

105

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

106

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.

Mohanraj.C

2013-02-01

107

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

2012-02-01

108

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

109

Kiikuv maja / Anu Arm  

Index Scriptorium Estoniae

Eesti Kunstiakadeemia esimese kursuse arhitektuuriüliõpilaste II semestri töö. Juhendaja arhitekt Andres Alver, ehitamise Pedaspeale organiseeris suvepraktika juhendaja arhitekt Jaan Tiidemann. Autor Anu Arm, kaasa töötasid ja valmis ehitasid: Ott Alver, Maarja Elm, Mari Hunt, Alvin Järving, Marten Kaevats, Riho Kerge, Reedik Poopuu, Anu Põime, Helen Rebane, Kaisa Saarva, Martin Tago, Reet Volt. Valmis: 19. VIII 2006

Arm, Anu

2006-01-01

110

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

111

Replantation (Finger, Hand, or Arm)  

Science.gov (United States)

... your collection. DESCRIPTION “Replantation” refers to the surgical reattachment of a finger, hand, or arm that has ... AND SYMPTOMS TREATMENT Replantation refers to the surgical reattachment of a finger, hand, or arm that has ...

112

The Journal Synthesizing Activity.  

Science.gov (United States)

The journal synthesizing activity is intended to combine aspects of the formal essay with that of a diary. Activities associated with lecture topics are written up as short journal entries of approximately five typewritten pages and are turned in during the weekly class session at which the related topic is being discussed. The journal project…

Garber, Zev

113

Inorganic syntheses, v.64  

CERN Multimedia

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

114

Method of Synthesizing Chlorozotocin.  

Science.gov (United States)

This invention relates to a two-step method of synthesizing 2-(3- (2-chloroethyl)-3-nitrosoureido)-2-deoxy-D-glucopyranose by (a) reacting glucosamine hydrochloride (I) and 2-chloroethylisocyanate in alkaline aqueous milieu in the presence of sodium carbo...

H. Dubicki J. L. Parsons R. J. Schultz D. F. Starks F. W. Starks

1979-01-01

115

Intelligence and Arms Control Policy.  

Science.gov (United States)

Deals with the relationship between military intelligence and arms control policy. Presents an overview of intelligence as it relates to arms control verification, focusing on monitoring and verification. Includes a summary of the history of unilateral statements. Concludes that there are both technical and political bases for arms control…

Shulsky, Abram N.

1989-01-01

116

Synthesis, Structures, and Reactions of Manganese Complexes Containing Diphosphine Ligands With Pendant Amines  

Energy Technology Data Exchange (ETDEWEB)

Addition of the pendant amine ligand PNRP (PNRP = Et2PCH2NRCH2PEt2; R = Me, Ph, n-Bu) to Mn(CO)5Br gives fac-Mn(PNRP)(CO)3Br. Photolysis of fac-Mn(PNRP)(CO)3Br with dppm [dppm = 1,2-bis(diphenylphosphino)methane] provides mixed bis(diphosphine) complexes, trans-Mn(PNRP)(dppm)(CO)(Br). Reaction of trans-Mn(PNRP)(dppm)(CO)(Br) with LiAlH4 leads to trans-Mn(PNRP)(dppm)(CO)(H). The crystal structure of trans-Mn(PNMeP)(dppm)(CO)(H) determined by x-ray diffraction shows an unusual distortion of the Mn-H towards one C-H of the dppm ligand, resulting in an H Mn CO angle of 155(1)° and C H • • • H Mn distance of 2.10(3) Å. Mn(P2PhN2Bn)(dppm)(CO)(H) [P2PhN2Bn = 1, 5-diphenyl-3,7-dibenzyl-1,5-diaza-3,7-diphosphacyclooctane] can be prepared in a similar manner; its structure has one chelate ring in a chair conformation and the second in a boat conformation. The boat-conformer ring directs the nitrogen of the ring towards the carbonyl ligand, and the N • • • C distance between one N of the P2PhN2Bn ligand and CO is 3.171(4) Å, indicating a weak interaction between the N of the pendant amine and the CO ligand. Reaction of NaBArF4 (ArF = = 3,5-bis(trifluoromethyl)phenyl) with Mn(P P)(dppm)(CO)(Br) produces the cations [Mn(P P)(dppm)(CO)]+. The crystal structure of [Mn(PNMeP)(dppm)(CO)][BArF4] shows two very weak agostic interactions between C-H bonds on the phenyl ring and the Mn. The cationic complexes [Mn(P P)(dppm)(CO)]+ react with H2 to form dihydrogen complexes [Mn(H2)(P P)(dppm)(CO)]+ (Keq = 1 - 90 atm-1 in fluorobenzene, for a series of different P P ligands). Similar equilibria with N2 produce [Mn(N2)(P P)(dppm)(CO)]+ (Keq generally 1-3.5 atm-1 in fluorobenzene). This work was supported by the US Department of Energy Basic Energy Sciences' Chemical Sciences, Geosciences & Biosciences Division. Pacific Northwest National Laboratory is operated by Battelle for the US Department of Energy.

Welch, Kevin D.; Dougherty, William G.; Kassel, W. S.; DuBois, Daniel L.; Bullock, R. Morris

2010-10-01

117

Thermochemical and Mechanistic Studies of Electrocatalytic Hydrogen Production by Cobalt Complexes Containing Pendant Amines  

Energy Technology Data Exchange (ETDEWEB)

Two cobalt(tetraphosphine) complexes [Co(PnC-PPh22NPh2)(CH3CN)](BF4)2 with a tetradentate phosphine ligand (PnC-PPh22NPh2 = 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 studied for electrocatalytic hydrogen production using 1:1 [(DMF)H]+:DMF. A turnover frequency of 980 s–1 with an overpotential of 1210 mV was measured for [CoII(L2)(CH3CN)]2+, and a turnover frequency of 980 s–1 with an overpotential of 930 mV was measured for [CoII(L3)(CH3CN)]2+. Addition of water increases the turnover frequency of [CoII(L2)(CH3CN)]2+ to 19,000 s–1. The catalytic wave for each of these complexes occurs at the reduction potential of the corresponding HCoIII complex. Comprehensive thermochemical studies of [CoII(L2)(CH3CN)]2+ and [CoII(L3)(CH3CN)]2+ and species derived from them by addition/removal of protons/electrons were carried out using values measured experimentally and calculated using DFT. Notably, HCoI(L2) and HCoI(L2) were found to be remarkably strong hydride donors, with HCoI(L2) being a better hydride donor than BH4-. Mechanistic studies of these catalysts reveal that H2 formation can occur by protonation of a HCoII intermediate, and that the pendant amines of these complexes facilitate proton delivery to the cobalt center. The rate-limiting step for catalysis is a net intramolecular isomerization of the protonated pendant amine from the non-productive exo-isomer to the productive endo isomer. We thank Dr. Shentan Chen for many helpful discussions. This research 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. Computational resources were provided at the National Energy Research Scientific Computing Center (NERSC) at Lawrence Berkeley National Laboratory. Pacific Northwest National Laboratory is operated by Battelle for the U.S. Department of Energy.

Wiedner, Eric S.; Appel, Aaron M.; DuBois, Daniel L.; Bullock, R. Morris

2013-12-16

118

Photovoltaic Effect of Bilayer Solid-State Cell with Polysiloxane Pendant Tris( 2,2?-bipyridyl)ruthenium Complex  

Science.gov (United States)

A solid-state photoelectrochemical device was fabricated with a poly-siloxane pendant tris(2,2'-bipyridyl)ruthenium complex [ PSiO Ru(bpy)32+] as a photosensitizer layer and a polysiloxane pendant methylviologen [ PSiO MV2+] as an electron acceptor layer. In the dark, the SnO2/PSiO MV2+/PSiO Ru(bpy)32+/Ag solid-state cell showed rectification characteristics. Photocurrent was obtained in the bilayer solid-state cell upon illumination of visible light, which was caused by the photoexcitation of the Ru(bpy)32+ and successive electron transfer to the MV2+. The short-circuit photocurrent of 0.485 µ A· cm-2 was obtained with the intensity of illumination of 34 mW· cm-2.

Yamada, Katsumi; Kobayashi, Norihisa; Ikeda, Koji; Hirohashi, Ryo; Kaneko, Masao

1994-04-01

119

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

120

Safeguarding arms control  

International Nuclear Information System (INIS)

This essay reviews the evolution of various safeguards concepts associated with U.S. Soviet arms control negotiations over the past twenty-five years. It explore in some detail the origins, nature, and effectiveness of the safeguards packages associated with six agreements: the Limited Test Ban Treaty (1963), the SALT I Interim Agreement (1972), the Anti-Ballistic Missile (ABM) Treaty (1972), the Threshold Test Ban Treaty (1974), the Peaceful Nuclear Explosions Treaty (1976) and the SALT II Treaty (1979). Finally, the implications of this historical record for developing future nuclear and conventional arms control accords and for shoring up existing pacts, such as the ABM Treaty, are assessed with a view towards practicable prescriptions for Western policymakers. The treaty eliminating intermediate-range nuclear forces (INF) incorporates several verification safeguards, and it is very likely that analogous measures would be attached to any accord constraining conventional forces in Europe

1988-01-01

 
 
 
 
121

ARM User Survey Report  

Energy Technology Data Exchange (ETDEWEB)

The objective of this survey was to obtain user feedback to, among other things, determine how to organize the exponentially growing data within the Atmospheric Radiation Measurement (ARM) Climate Research Facility, and identify users’ preferred data analysis system. The survey findings appear to have met this objective, having received approximately 300 responses that give insight into the type of work users perform, usage of the data, percentage of data analysis users might perform on an ARM-hosted computing resource, downloading volume level where users begin having reservations, opinion about usage if given more powerful computing resources (including ability to manipulate data), types of tools that would be most beneficial to them, preferred programming language and data analysis system, level of importance for certain types of capabilities, and finally, level of interest in participating in a code-sharing community.

Roeder, LR

2010-06-22

122

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

123

Pyridine derivative covalently bonded on chitosan pendant chains for textile dye removal.  

Science.gov (United States)

Chitosan was chemically modified through a sequence of four reactions with immobilized 2-aminomethylpyridine at the final stage, after prior protection of amino group with benzaldehyde. The characterized biopolymers containing free amino and hydroxyl active centers on the biopolymeric structure and pyridinic nitrogen on pendant chains showed combined hydrophobic properties that can potentially favor interactions. Reactive Yellow GR and Blue RN dyes gave the maximum sorption capacities of 2.13 and 1.61 mmol g(-1), which were performed as functions of contact time, concentration and dye structure. However, biopolymer/dye interactions are governed by effective hydrogen bond and van der Waals forces for such structural adjustments. The data obtained from the concentration isotherm were applied to non-linear regressions of the Langmuir, the Freundlich and the Sips models, with the best fit to the latter model. The kinetic data was fitted to non-linear regression of pseudo-second-order, indicating that the sorption phenomena are most likely to be controlled by chemisorption process. PMID:24507253

Oliveira, Cintia S; Airoldi, Claudio

2014-02-15

124

Folding graft copolymer with pendant drug segments for co-delivery of anticancer drugs.  

Science.gov (United States)

A graft copolymer with pendant drug segments can fold into nanostructures in a protein folding-like manner. The graft copolymer is constructed by directly polymerizing ?-camptothecin-glutamate N-carboxyanhydride (Glu(CPT)-NCA) on multiple sites of poly(ethylene glycol) (PEG)-based main chain via the ring open polymerization (ROP). The "purely" conjugated anticancer agent camptothecin (CPT) is hydrophobic and serves as the principal driving force during the folding process. When exposed to water, the obtained copolymer, together with doxorubicin (Dox), another anticancer agent, can fold into monodispersed nanocarriers (with a diameter of around 50 nm) for dual-drug delivery. Equipped with a PEG shell, the nanocarriers displayed good stability and can be internalized by a variety of cancer cell lines via the lipid raft and clathrin-mediated endocytotic pathway without premature leakage, which showed a high synergetic activity of CPT and Dox toward various cancer cells. In vivo study validated that the nanocarriers exhibited strong accumulation in tumor sites and showed a prominent anticancer activity against the lung cancer xenograft mice model compared with free drugs. PMID:24875756

Tai, Wanyi; Mo, Ran; Lu, Yue; Jiang, Tianyue; Gu, Zhen

2014-08-01

125

Polyurethane cationomers with pendant trimethylammonium groups. 1: Fourier transform infrared temperature studies  

Energy Technology Data Exchange (ETDEWEB)

Specific interactions are investigated in a series of polyether-polyurethane cationomers containing pendant trimethylammonium groups, with ion contents ranging from 0 to 0.88 mequiv/g, using Fourier transform infrared temperature studies. Hydrogen bonding of urethane N-H groups to urethane carbonyls, which has been extensively reported in conventional polyurethanes, is also evident in these materials. Additionally, the N-H stretching region shows significant contributions from N-H groups hydrogen bonded to ether oxygens of the soft segments in the homogeneous un-ionized polyurethane and to neutralizing anions in the cationomers. Spectral deconvolution and mass balances are used to obtain semiquantitative information on the extent of hydrogen bonding to the various proton acceptors as a function of temperature. As the temperature of the un-ionized sample is increased from 30 to 140 C, hydrogen bonding of N-H groups to polyether oxygens decreases, while hydrogen bonding to urethane carbonyls increases. A similar redistribution of N-H hydrogen bonds, from the anion to carbonyl groups with increasing temperature, is observed for the cationomers. The results for each polymer are related to its chemical structure, thermomechanical properties, and morphology.

Goddard, R.J.; Copper, S.L. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Chemical Engineering

1995-02-27

126

Two new inorganic-organic hybrid single pendant hexadecavanadate derivatives with bifunctional electrocatalytic activities  

International Nuclear Information System (INIS)

Two new supramolecular assembly hexadecavanadate derivatives of H2[Cd(phen)3]2{[Cd(H2O)(phen)2](V16O38Cl)}.2.5H2O 1 (phen = 1,10'-phenanthroline) and H2[Cd(bipy)3][Cd(H2O)(bipy)2]{[Cd(H2O)(bipy)2](V16O38Cl)}.1.5H2O 2 (bipy 2,2'-bipyridine), have been prepared under mild hydrothermal conditions and structurally characterized by IR, XPS spectra, TG analyses and single-crystal X-ray diffraction. Compounds 1 and 2 are constructed from single pendant [CdL2] (L = phen, 1 and L = bipy, 2) modified hexadecavanadates. The hybrids 1 and 2 were used as solid bulk modifier to fabricate bulk-modified carbon paste electrodes (CPEs) (1-CPE and 2-CPE) by direct mixing. The electrochemical behaviors and electrocatalysis of 1-CPE and 2-CPE indicate bifunctional electrocatalytic activities toward both the oxidation and reduction of nitrite. Furthermore, their electrocatalytic activities toward the reduction of bromate and oxidation of ascorbic acid are also studied in 1 M H2SO4 aqueous solutions

2007-03-01

127

Two new inorganic-organic hybrid single pendant hexadecavanadate derivatives with bifunctional electrocatalytic activities  

Energy Technology Data Exchange (ETDEWEB)

Two new supramolecular assembly hexadecavanadate derivatives of H{sub 2}[Cd(phen){sub 3}]{sub 2}{l_brace}[Cd(H{sub 2}O)(phen){sub 2}](V{sub 16}O{sub 38}Cl){r_brace}.2.5H{sub 2}O 1 (phen = 1,10'-phenanthroline) and H{sub 2}[Cd(bipy){sub 3}][Cd(H{sub 2}O)(bipy){sub 2}]{l_brace}[Cd(H{sub 2}O)(bipy){sub 2}](V{sub 16}O{sub 38}Cl){r_brace}.1.5H{sub 2}O 2 (bipy 2,2'-bipyridine), have been prepared under mild hydrothermal conditions and structurally characterized by IR, XPS spectra, TG analyses and single-crystal X-ray diffraction. Compounds 1 and 2 are constructed from single pendant [CdL{sub 2}] (L = phen, 1 and L = bipy, 2) modified hexadecavanadates. The hybrids 1 and 2 were used as solid bulk modifier to fabricate bulk-modified carbon paste electrodes (CPEs) (1-CPE and 2-CPE) by direct mixing. The electrochemical behaviors and electrocatalysis of 1-CPE and 2-CPE indicate bifunctional electrocatalytic activities toward both the oxidation and reduction of nitrite. Furthermore, their electrocatalytic activities toward the reduction of bromate and oxidation of ascorbic acid are also studied in 1 M H{sub 2}SO{sub 4} aqueous solutions.

Dong, Baoxia [Key Laboratory of Polyoxometalate Science of Ministry of Education, Faculty of Chemistry, Northeast Normal University, Changchun, Jilin 130024 (China); Peng, Jun [Key Laboratory of Polyoxometalate Science of Ministry of Education, Faculty of Chemistry, Northeast Normal University, Changchun, Jilin 130024 (China)]. E-mail: jpeng@nenu.edu.cn; Tian, Aixiang [Key Laboratory of Polyoxometalate Science of Ministry of Education, Faculty of Chemistry, Northeast Normal University, Changchun, Jilin 130024 (China); Sha, Jingquan [Key Laboratory of Polyoxometalate Science of Ministry of Education, Faculty of Chemistry, Northeast Normal University, Changchun, Jilin 130024 (China); Li, Li [Key Laboratory of Polyoxometalate Science of Ministry of Education, Faculty of Chemistry, Northeast Normal University, Changchun, Jilin 130024 (China); Liu, Hongsheng [Key Laboratory of Polyoxometalate Science of Ministry of Education, Faculty of Chemistry, Northeast Normal University, Changchun, Jilin 130024 (China)

2007-03-01

128

Polymer pendant crown thioethers for removal of mercury from acidic wastes  

Energy Technology Data Exchange (ETDEWEB)

Removal and immobilization of mercury ions from industrial waste streams is a difficult and expensive problem requiring an efficient and selective extractant that is resistant to corrosive conditions. We have now developed an acid-resistant thiacrown polymer that has potential utility as a selective and cost-effective Hg2+ extractant. Copolymerization of a novel C-substituted thiacrown, N,N-(4-vinylbenzylmethyl)-2-aminomethyl- ,4,&l 1,14- pentathiacycloheptadecane, with DVB (80% divinylbenzene) using a radical initiator generated a highly cross-linked polymer containing pendant thiacrowns. Mercury extraction capabilities of the polymer were tested in acidic media (pH range: 1.5 to 6.2) and the extraction of Hg2+ was determined to be 95+% with a mixing time of 30 minutes. The thiacrown polymer was also determined to be selective for Hg*+, competing ions such as Pb2+, Cd2+, A13+, and Fe3+. even in the presence of high concentrations of The bound Hg2+ ions can then be stripped from the polymer, allowing the polymer to be reused without significant loss of loading capacity.

Baumann, T F; Fox, G A; Reynolds, J

1998-12-22

129

Best Arm Identification in Multi-Armed Bandits  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We consider the problem of finding the best arm in a stochastic multi-armed bandit game. The regret of a forecaster is here defined by the gap between the mean reward of the optimal arm and the mean reward of the ultimately chosen arm. We propose a highly exploring UCB policy and a new algorithm based on successive rejects. We show that these algorithms are essentially optimal since their regret decreases exponentially at a rate which is, up to a logarithmic factor, the best possible. However...

Audibert, Jean-yves; Bubeck, Se?bastien

2010-01-01

130

Disarmament and arms control  

International Nuclear Information System (INIS)

This report discusses how far science and technology can provide methods of making arms control and disarmament agreements more controlable in an objective way. Two case studies have been considered, the test ban treaty and the verification of the number of strategic nuclear weapons. These lead to the conclusion that both science and politics are closely interwoven and that within what appear to be scientific arguments, political positions are being defended. Consequently scientists and technologists and the contexts in which they work, play a prominent role. (C.F.)

1979-01-01

131

Relating feedstock composition to product slate and composition in catalytic cracking. 4. An extended pendant-core model for gasoline composition  

Energy Technology Data Exchange (ETDEWEB)

The pendant-core concept has been used previously to predict product slates from catalytic cracking. In this concept, alkyl side chains and analogous moieties are defined as `pendants` which are attached to a cluster of aromatic and/or naphthenic rings which is referred to as the `core`. This work extends the pendant-core concept via a model which correlates feed composition (19 main component types determined by mass spectroscopy) to nine product subclasses (both gasoline and non-gasoline) by adding product distribution functions. These product distribution functions depend upon the feed component class (saturates, aromatics, and sulfur compounds) and upon the core-pendant ratio. For example, the production of light gas and coke increases with the core-pendant ratio since the probability of coke formation increases with core size and the average pendant chain length decreases as the proportion of carbon in pendants decreases. Using these component distribution functions, and the mass spectroscopic analysis of feeds, one can calculate anticipated yields of nine product subclasses: light gas, C{sub 3}/C{sub 4} gas, light cycle oils, heavy cycle oils, coke, and gasoline range: paraffins, olefins, aromatics and naphthenes. The product distribution functions were developed from data on four feedstocks. For the four feedstocks used in the correlation, plus a fifth feedstock, the predicted product quantities are within 2 wt % of the experimental values. The present form of the model does not address effects of polar (acidic or basic) compounds in feeds on product slate. 28 refs., 8 figs., 3 tabs.

Sheppard, C.M.; Green, J.B.; Vanderveen, J.W. [BDM Petroleum Technologies, Bartlesville, OK (United States)

1998-03-01

132

Polymer pendant crown thioethers for removal of mercury from acidic wastes: synthesis, characterization and application  

Energy Technology Data Exchange (ETDEWEB)

Removal of mercury ions from industrial waste streams is a difficult and expensive problem requiring an efficient and selective extractant that is resistant to corrosive conditions. We have now developed an acid-resistant thiacrown polymer that has potential utility as a selective and cost-effective Hg{sup 2+} extractant. Copolymerization of a novel C-substituted thiacrown, N,N-(4-vinylbenzylmethyl)-2-aminomethyl-1,4,8,11,14-pentathiacycloheptadecane, with DVB (80% divinylbenzene) using a radical initiator generated a highly cross-linked polymer containing pendant thiacrowns. Mercury extraction capabilities of the polymer were tested in acidic media (pH range: 1.5 to 6.2) and the extraction of Hg{sup 2+} was determined to be 95% at a mixing time of 30 minutes. The thiacrown polymer was also determined to be selective for Hg{sup 2+}, even in the presence of high concentrations of competing ions such as Pb{sup 2+}, Cd{sup 2+}, Al{sup 3}, and Fe{sup 3+}. The bound Hg{sup 2+} ions can then be stripped from the polymer, allowing the polymer to be reused without significant loss of loading capacity. The binding of Hg{sup 2+} to the polymer has been examined by X-ray photoemission spectroscopy. The thiacrown appears unaffected by incorporation into the polymer and the Hg{sup 2+} appears to be bound to the polymer complex in a similar manner as Hg{sup 2+} is bound in monomeric thiacrowns containing five sulfur atoms.

Reynolds, J G; Baumann, T F; Nelson, A J; Fox, G A

2000-07-21

133

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

134

Adaptive Control For Cooperative Dual Robot Arms  

Science.gov (United States)

Three strategies proposed for adaptive control of two cooperative robot arms. New dual-arm control strategies implemented at low level of control hierarchy. Each arm operated independently under single-arm control scheme treating forces and torques transmitted through load as though disturbances. Yields promising results in numerical simulations, and general approach extended to greater numbers of arms.

Seraji, Homayoun

1989-01-01

135

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  

Energy Technology Data Exchange (ETDEWEB)

A comparison between [Al{center_dot}1]{sup 3+} and [Zn{center_dot}1]{sup 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 I{sub p} and electron affinity E{sub a} parameters for the [Al{center_dot}1]{sup 3+} (I{sub p} = 5.82eV, E{sub a} = 2.80eV) and [Zn{center_dot}1]{sup 2+} (I{sub p} = 5.67eV, E{sub a} = 2.32eV) evidenced that the [Al{center_dot}1]{sup 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{center_dot}1]{sup 3+} systems expected from the energy level diagrams.

Bagatin, Izilda A. [Instituto de Quimica, Universidade de Sao Paulo, Cx. P.: 26077, CEP 05513-970, Sao Paulo, SP (Brazil)], E-mail: izildabagatin@yahoo.com.br; Legnani, Cristiano [Divisao de Metrologia em Materiais, Instituto Nacional de Metrologia, Normalizacao e Qualidade Industrial, CEP 25250-020, Duque de Caxias, RJ (Brazil); Cremona, Marco [Divisao de Metrologia em Materiais, Instituto Nacional de Metrologia, Normalizacao e Qualidade Industrial, CEP 25250-020, Duque de Caxias, RJ (Brazil); Pontificia Universidade Catolica do Rio de Janeiro, Depto de Fisica, C.P.38071, Rio de Janeiro (Brazil)

2009-01-01

136

Early transition metal complexes bearing a C-capped tris(phenolate) ligand incorporating a pendant imine arm: synthesis, structure, and ethylene polymerization behavior.  

Science.gov (United States)

The ligand 3-[2,2'-methylenebis(4,6-di- tert-butylphenol)-5- tert-butylsalicylidene-(2,6-diisopropyl)phenylimine] (L(1)H 3) was reacted with MCl 4 (M = Ti, Zr) or MCl 5 (M = Nb, Ta) to give complexes of the type [MCl 2(L(1)H 2) 2] (M = Ti (1); Zr (2)), [NbCl 3( L (1)H)] (3), or [TaCl 4(L(1)H 2)] (4), respectively. Single crystal X-ray diffraction of 1- 4 revealed common "iminium" species resulting in zwitterionic complexes. Reaction of [V(N p-tol)(O n-Pr) 3] with L (1)H3 afforded [{(VN p-tol)(L(1)H)} 2(mu-O n-Pr)2] (5), and a second complex [(VO) 2(mu-O)(L(3)H) 2] (6)(L(3)H being derived from 3-[2,2'-methylenebis(4,6-di-tert-butylphenol)-5-tert-butylsalicylidene- p-tolylimine]). The condensation reaction between 3-[2,2'-methylenebis(4,6-di-tert-butylphenol)-5-tert-butyl-2-hydroxybenzaldehyde] (L(0)H 3) and o-phenylenediamine (1,2-diaminobenzene) afforded two products: a pseudo-16-membered hydrogen bonded macrocyclic structure {1,2-bis-3-[2,2'-methylenebis(4,6-di-tert-butylphenol)-5-tert-butylsalicylidene-benzyldiimine]} (L(5)H6), or the benzimidazolyl bearing ligand (L(6)H 3). The reaction of L (5)H6 or L(6)H 3 with [VO(O n-Pr) 3] under varying conditions produced the complexes [(VO)(L(5)H 4)] (7), [(VO) 2(L(5)H)] (8), or [VO(L(6)H 2) 2] (9). L (0)H 3 was reacted with a number of anilines to give the proligands {3-[2,2'-methylenebis(4,6-di- tert-butylphenol)-5-tert-butylsalicylidene-R-imine]}, where R = NC 6H 5 (L(2)H3), NC 6H 4-Me (L(3)H 3), and NC 6H 2-Me 3 (L(4)H 3). Reactions of these ligands with [VO(O n-Pr) 3] formed bischelating complexes of the form [(VO)(L(2-4)H 2)2] (10, 11, and 12, respectively). The reaction of L (1)H 3 with trimethylaluminum led to a bis-aluminum complex {(AlMe 2)[AlMe(NCMe)] L (1)} (13). The ability of complexes 1-12 to polymerize ethylene in the presence of an organoaluminum cocatalyst was investigated. Procatalysts 1 and 2 were found to produce negligible activities in the presence of dimethylaluminum chloride (DMAC) and the reactivator ethyltrichloroacetate (ETA), whereas 3 and 4 were found to be completely inactive for polymerization using a variety of different organoaluminum cocatalysts. Using the combination of DMAC and ETA, complexes 5-12 were found to be highly active catalysts; in all cases, the polymer formed was of high molecular weight linear polyethylene. PMID:18529049

Homden, Damien; Redshaw, Carl; Wright, Joseph A; Hughes, David L; Elsegood, Mark R J

2008-07-01

137

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

138

Oxidative synthesis of a novel polyphenol having pendant Schiff base group: Synthesis, characterization, non-isothermal decomposition kinetics  

Energy Technology Data Exchange (ETDEWEB)

Research highlights: {yields} In this study, the synthesis and thermal characterization of a new functional polyphenol are reported. {yields} Non-isothermal methods were used to evaluate the thermal decomposition kinetics of resulting polymer. {yields} Thermal decomposition of polymer follows a diffusion type kinetic model. {yields} It is noted that this kinetic model is quite rare in polymer degradation studies. - Abstract: In here, the facile synthesis and thermal characterization of a novel polyphenol containing Schiff base pendant group, poly(4-{l_brace}[(4-hydroxyphenyl)imino]methyl{r_brace}benzene-1,2,3-triol) [PHPIMB], are reported. UV-vis, FT-IR, {sup 1}H NMR, {sup 13}C NMR, GPC, TG/DTG-DTA, CV (cyclic voltammetry) and solid state conductivity measurements were utilized to characterize the obtained monomer and polymer. The spectral analyses results showed that PHPIMB was composed of polyphenol main chains containing Schiff base pendant side groups. Thermal properties of the polymer were investigated by thermogravimetric analyses under a nitrogen atmosphere. Five methods were used to study the thermal decomposition of PHPIMB at different heating rate and the results obtained by using all the kinetic methods were compared with each other. The thermal decomposition of PHPIMB was found to be a simple process composed of three stages. These investigated methods were those of Flynn-Wall-Ozawa (FWO), Tang, Kissinger-Akahira-Sunose (KAS), Friedman and Kissinger methods.

Dilek, Deniz [Faculty of Education, Secondary Science and Mathematics Education, Canakkale Onsekiz Mart University, 17100 Canakkale (Turkey); Dogan, Fatih, E-mail: fatihdogan@comu.edu.tr [Faculty of Education, Secondary Science and Mathematics Education, Canakkale Onsekiz Mart University, 17100 Canakkale (Turkey); Bilici, Ali, E-mail: alibilici66@hotmail.com [Control Laboratory of Agricultural and Forestry Ministry, 34153 Istanbul (Turkey); Kaya, Ismet [Department of Chemistry, Faculty of Science and Arts, Canakkale Onsekiz Mart University, Canakkale (Turkey)

2011-05-10

139

Test-retest reliability of a pendant-worn sensor device in measuring chair rise performance in older persons.  

Science.gov (United States)

Chair rise performance is incorporated in clinical assessments to indicate fall risk status in older persons. This study investigated the test-retest reliability of a pendant-sensor-based assessment of chair rise performance. Forty-one older persons (28 females, 13 males, age: 72-94) were assessed in two sessions with 3 to 8 days in between. Repeated chair rise transfers were measured after different instructions. Relative and absolute test-retest reliability of chair rise measurements in individual tests and average over all tests were evaluated by means of intra-class correlation coefficients (ICCs) and standard error of measurement (SEM) as a percentage of the measurement mean. Systematic bias between the measurements in test and retest was examined with paired t-tests. Heteroscedasticity of the measurements was visually checked with Bland-Altman plots. In the different test conditions, the ICCs ranged between 0.63 and 0.93, and the SEM% ranged between 5.7% and 21.2%. The relative and absolute reliability of the average over all tests were ICC = 0.86 and SEM% = 9.5% for transfer duration, ICC = 0.93 and SEM% = 9.2% for maximum vertical acceleration, and ICC = 0.89 and SEM% = 10.0% for peak power. The results over all tests indicated that a fall risk assessment application based on pendant-worn-sensor measured chair rise performance in daily life might be feasible. PMID:24841248

Zhang, Wei; Regterschot, G Ruben H; Schaabova, Hana; Baldus, Heribert; Zijlstra, Wiebren

2014-01-01

140

Test-Retest Reliability of a Pendant-Worn Sensor Device in Measuring Chair Rise Performance in Older Persons  

Directory of Open Access Journals (Sweden)

Full Text Available Chair rise performance is incorporated in clinical assessments to indicate fall risk status in older persons. This study investigated the test-retest reliability of a pendant-sensor-based assessment of chair rise performance. Forty-one older persons (28 females, 13 males, age: 72–94 were assessed in two sessions with 3 to 8 days in between. Repeated chair rise transfers were measured after different instructions. Relative and absolute test-retest reliability of chair rise measurements in individual tests and average over all tests were evaluated by means of intra-class correlation coefficients (ICCs and standard error of measurement (SEM as a percentage of the measurement mean. Systematic bias between the measurements in test and retest was examined with paired t-tests. Heteroscedasticity of the measurements was visually checked with Bland-Altman plots. In the different test conditions, the ICCs ranged between 0.63 and 0.93, and the SEM% ranged between 5.7% and 21.2%. The relative and absolute reliability of the average over all tests were ICC = 0.86 and SEM% = 9.5% for transfer duration, ICC = 0.93 and SEM% = 9.2% for maximum vertical acceleration, and ICC = 0.89 and SEM% = 10.0% for peak power. The results over all tests indicated that a fall risk assessment application based on pendant-worn-sensor measured chair rise performance in daily life might be feasible.

Wei Zhang

2014-05-01

 
 
 
 
141

Oxidative synthesis of a novel polyphenol having pendant Schiff base group: Synthesis, characterization, non-isothermal decomposition kinetics  

International Nuclear Information System (INIS)

Research highlights: ? In this study, the synthesis and thermal characterization of a new functional polyphenol are reported. ? Non-isothermal methods were used to evaluate the thermal decomposition kinetics of resulting polymer. ? Thermal decomposition of polymer follows a diffusion type kinetic model. ? It is noted that this kinetic model is quite rare in polymer degradation studies. - Abstract: In here, the facile synthesis and thermal characterization of a novel polyphenol containing Schiff base pendant group, poly(4-{[(4-hydroxyphenyl)imino]methyl}benzene-1,2,3-triol) [PHPIMB], are reported. UV-vis, FT-IR, 1H NMR, 13C NMR, GPC, TG/DTG-DTA, CV (cyclic voltammetry) and solid state conductivity measurements were utilized to characterize the obtained monomer and polymer. The spectral analyses results showed that PHPIMB was composed of polyphenol main chains containing Schiff base pendant side groups. Thermal properties of the polymer were investigated by thermogravimetric analyses under a nitrogen atmosphere. Five methods were used to study the thermal decomposition of PHPIMB at different heating rate and the results obtained by using all the kinetic methods were compared with each other. The thermal decomposition of PHPIMB was found to be a simple process composed of three stages. These investigated methods were those of Flynn-Wall-Ozawa (FWO), Tang, Kissinger-Akahira-Sunose (KAS), Friedman and Kissinger methods.

2011-05-10

142

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

143

A modular synthesis of dithiocarbamate pendant unnatural a-amino acids  

Science.gov (United States)

Unnatural a-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...

144

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

Science.gov (United States)

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. PMID:23338944

Yamada, Mihoko; Tashiro, Shohei; Miyake, Ryosuke; Shionoya, Mitsuhiko

2013-03-14

145

Design of Robotic Arm Control System Mimics Human Arm Motion  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents a control system to make the robotic hand mimic human hand motion in real time and offline mode. The human hand tracking system is a wearable sensing arm (potentiometers) used to determine the position in space and to sense the grasping task of human hand. The maskable sensing arm was designed with same geometrical arrangement of robotic hand that needs to be controlled. The control software of a robot was implemented using Visual Basic and supported with graphical user in...

Salam Al-ammri, A.; Taki, Ghaith A.

2013-01-01

146

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

147

Arms Control at the Crossroads.  

Science.gov (United States)

If the United States can lower its expectations just enough, it can put together a series of agreements which will constitute an arms control breakthrough that will serve our interests for decades to come. (Author/RM)

Bumpers, Dale

1985-01-01

148

Technology and the arms race  

International Nuclear Information System (INIS)

This article makes a review of the book Innovation and the Arms Race: How the United States and the Soviet Union Develop New Military Technologies written by Matthew Evangelista. For at least the last two decades, scholars have struggled to come to grips with the role of technological change in the arms race. Possible relationships between theories on technology and politics are examined. The contrasts between U.S. and Soviet approaches are highlighted

1988-01-01

149

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

Energy Technology Data Exchange (ETDEWEB)

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 {sup 13}C (CP/MAS) and {sup 29}Si (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 m{sup 2} g{sup -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. - Graphical Abstract: The mesoporous SBA-16 can be synthesized from binary (F127/TEOS) or ternary (F127/alcohol/TEOs) systems to give well-ordered mesoporous silicas. The co-templates ethanol or butanol gave the final material with highest wall thickness, mainly with ethanol. After these syntheses the pores were successfully organofunctionalized to give a good incorporation of the silylating agents. The final silicas presented of well-arranged solid characteristics as expressing by three distinct peaks, as indexed by the corresponding planes. Highlights: Black-Right-Pointing-Pointer Syntheses of mesoporous silicas by using ternary (F127/agent/TEOS) and binary (F127/TEOS) systems. Black-Right-Pointing-Pointer Use of co-templates to synthesize mesoporous silicas with larger wall thicknesses. Black-Right-Pointing-Pointer Immobilization of pendant chains inside the porous silicas. Black-Right-Pointing-Pointer Ordered mesoposous silicas as new materials for possible applications on sorption and delivering drug systems.

Oliveira, Vaeudo V. [Institute of Chemistry, University of Campinas, UNICAMP, PO Box 6154, 13084-971 Campinas, SP (Brazil); Airoldi, Claudio, E-mail: airoldi@iqm.unicamp.br [Institute of Chemistry, University of Campinas, UNICAMP, PO Box 6154, 13084-971 Campinas, SP (Brazil)

2012-12-15

150

Unequal-Arms Michelson Interferometers  

Science.gov (United States)

Michelson interferometers allow phase measurements many orders of magnitude below the phase stability of the laser light injected into their two almost equal-length arms. If, however, the two arms are unequal, the laser fluctuations can not be removed by simply recombining the two beams. This is because the laser jitters experience different time delays in the two arms, and therefore can not cancel at the photo detector. We present here a method for achieving exact laser noise cancellation, even in an unequal-arm interferometer. The method presented in this paper requires a separate readout of the relative phase in each arm, made by interfering the returning beam in each arm with a fraction of the outgoing beam. By linearly combining the two data sets with themselves, after they have been properly time shifted, we show that it is possible to construct a new data set that is free of laser fluctuations. An application of this technique to future planned space-based laser interferometer detector3 of gravitational radiation is discussed.

Tinto, Massimo; Armstrong, J. W.

2000-01-01

151

Algorithms for Unequal-Arm Michelson Interferometers  

Science.gov (United States)

A method of data acquisition and data analysis is described in which the performance of Michelson-type interferometers with unequal arms can be made nearly the same as interferometers with equal arms. The method requires a separate readout of the relative phase in each arm, made by interfering the returning beam in each arm with a fraction of the outgoing beam.

Giampieri, Giacomo; Hellings, Ronald W.; Tinto, Massimo; Bender, Peter L.; Faller, James E.

1994-01-01

152

Temperature-responsive porous films containing pendant ?-amino acid prepared by heavy ion irradiation  

International Nuclear Information System (INIS)

A new intelligent material which has a function of low temperature swelling and high temperature deswelling was synthesized by polymerizing ?-amino acid containing monomer. This monomer was copolymerized with diethyleneglycol-bis-allylcarbonate in order to obtain a porous film with a function of stimuli-response. Pores obtained by heavy ion irradiation on the film showed a reversible pore size variation in water by changing the temperature. (author)

1991-11-05

153

Synthesis and reactivity of molybdenum and tungsten bis(dinitrogen) complexes supported by diphosphine chelates containing pendant amines  

Energy Technology Data Exchange (ETDEWEB)

In this study, we report the synthesis and characterization of molybdenum bis(dinitrogen) complexes supported by two PNP diphosphine ligands, Mo(N{sub 2}){sub 2}(PNP){sub 2}; PNP = [(R{sub 2}PCH{sub 2}){sub 2}N(R'), R = Et (ethyl), Ph (phenyl); R'= Me (methyl), Bn (benzyl)], and a series of tungsten bis(dinitrogen) complexes containing one or two PNP ligands, W(N{sub 2}){sub 2}(dppe)(PNP) and W(N{sub 2}){sub 2}(PNP){sub 2}, respectively, and the analogues complexes without pendant amines for comparison. These Mo- and W-N{sub 2} complexes were characterized by NMR, IR, spectroscopy, cyclic voltammetry and structurally characterized by X-ray crystallography. In addition, reactivity of the complexes with CO is described.

Weiss, Charles J.; Groves, Amy N.; Mock, Michael T.; Dougherty, William G.; Kassel, W. S.; Helm, Monte L.; DuBois, Daniel L.; Bullock, R. Morris

2012-04-30

154

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

2013-07-01

155

Hydrogen bonding or transient coordination of pendant group: cause for liability in ligand substitution reaction of aminopolycarboxylatoruthenium (III) complexes  

International Nuclear Information System (INIS)

The rate of substitution of water molecule in [LRuIII(H2O)] complexes [L=ethylenediaminetetraacetate (EDTA) anion and N-hydroxyethylethylenediaminetriacetate (HEDTRA) anion] with Cl- ion has been studied spectrophotometrically in aqueous medium at 30degC. The rates of substitutions of Cl- in [LRuCl] with thiocyanate (SCN-) have also been studied as a function of SCN- concentration in the temperature range 30-50degC. In both the cases, ruthenium(III)-EDTA is found to be more reactive than the corresponding HEDTRA complex. Activation parameters ?Hsup(?) and ?Ssup(?) for the substitution of [LRuIIICl]-complexes with SCN- are determined and a suitable mechanism is proposed. The reactivity of [LRuIIICl]- towards SCN- substitution is discussed in terms of the transient coordination of the uncoordinated - COOH or -CH2 - OH pendant group which assist in the elimination of leaving group and ligation of substituting nucleophiles. (author). 12 refs., 2 tabs

1992-03-01

156

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

2011-12-01

157

Design of Robotic Arm Control System Mimics Human Arm Motion  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents a control system to make the robotic hand mimic human hand motion in real time and offline mode. The human hand tracking system is a wearable sensing arm (potentiometers used to determine the position in space and to sense the grasping task of human hand. The maskable sensing arm was designed with same geometrical arrangement of robotic hand that needs to be controlled. The control software of a robot was implemented using Visual Basic and supported with graphical user interface (GUI. The control algorithm depends on joint to joint mapping method to match between the motions at each joint of portable sensing arm with corresponding joint of a robot in order to make the robot mimic the motion.

A. Salam Al-Ammri

2013-01-01

158

Super Armed Glycosyl Donors : Conformational arming of thioglycosides by silylation  

DEFF Research Database (Denmark)

Glycosyl donors protected with bulky silyl protective groups (tert-butyldimethylsilyl, TBS), on the 2-, 3- and 4-OH groups were found to have superior reactivity compared with benzylated thioglucosides. The enhanced reactivity is explained by the stereoelectronic effects associated with the conformational change induced by the silylation: A TBS silylated thioglucoside donor have axial OR groups while a benzylated thioglucoside have equatorial OR groups leading to much more favorable charge-dipole interactions in the transition state. This concept could be used to create â??super armed' glucosyl, mannosyl, rhamnosyl and galactosyl donors, which could cross couple with the armed acceptors phenyl 2,3,4-tri-O-benzyl-Ã?-D-thioglucoside or phenyl 2,3,6-tri-O-benzyl-Ã?-D-thioglucoside to give the corresponding armed disaccharides in good to excellent yields.

Bols, Mikael; Pedersen, Christian Marcus

2007-01-01

159

Computing Free Energy Landscapes: Application to Ni-based Electrocatalysts with Pendant Amines for H2 Production and Oxidation  

Energy Technology Data Exchange (ETDEWEB)

A general strategy is reported for computational exploration of catalytic pathways of molecular catalysts. Our results are based on a set of linear free energy relationships derived from extensive electronic structure calculations that permit predicting the thermodynamics of intermediates, with accuracy comparable to experimental data. The approach is exemplified with the catalytic oxidation and production of H2 by [Ni(diphosphine)2]2+ electrocatalysts with pendant amines incorporated in the second coordination sphere of the metal center. The analysis focuses upon prediction of thermodynamic properties including reduction potentials, hydride donor abilities, and pKa values of both the protonated Ni center and pendant amine. It is shown that all of these chemical properties can be estimated from the knowledge of only the two redox potentials for the Ni(II)/Ni(I) and Ni(I)/Ni(0) couples of the non-protonated complex, and the pKa of the parent primary aminium ion. These three quantities are easily accessible either experimentally or theoretically. The proposed correlations reveal intimate details about the nature of the catalytic mechanism and its dependence on chemical structure and thermodynamic conditions such as applied external voltage and species concentration. This computational methodology is applied to exploration of possible catalytic pathways, identifying low and high-energy intermediates and, consequently, possibly avoiding bottlenecks associated with undesirable intermediates in the catalytic reactions. We discuss how to optimize some of the critical reaction steps in order to favor catalytically more efficient intermediates. The results of this study highlight the substantial interplay between the various parameters characterizing the catalytic activity, and form the basis needed to optimize the performance of this class of catalysts.

Chen, Shentan; Ho, Ming-Hsun; Bullock, R. Morris; DuBois, Daniel L.; Dupuis, Michel; Rousseau, Roger J.; Raugei, Simone

2014-01-03

160

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

2011-12-01

 
 
 
 
161

A facile strategy toward conjugated polyelectrolyte with oligopeptide as pendants for biological applications.  

Science.gov (United States)

We report a facile yet efficient strategy to synthesize biofunctionalized conjugated polyelectrolyte using click reaction between an amphiphilic oligopeptide (R10) and organic soluble polyfluorene (PF) as an example. PF-R10 shows the absorption and emission maxima at ~380 and ~430 nm in water, respectively. In addition, it exhibits enhanced fluorescence in acidic circumstance as compared to that in neutral environment because of reduced aggregation, which is confirmed by laser light scattering and atomic force microscopy studies. In view of the penetration property of the grafted R10 peptide, PF-R10 shows excellent cell uptake and labeling ability in cellular imaging. PMID:23444831

Liu, Jie; Feng, Guangxue; Geng, Junlong; Liu, Bin

2013-06-12

162

LBS-Lincoln Boolean Synthesizer.  

Science.gov (United States)

The Lincoln Boolean Synthesizer (LBS) creates custom integrated circuits from boolean equations. The currently supported integration technology is a fully customizable CMOS process with 5 micron channel width, P-tub and, one level of metal. This document ...

J. R. Southard A. Domic K. W. Crouch

1982-01-01

163

Battery saving frequency synthesizer arrangement  

International Nuclear Information System (INIS)

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

1985-01-01

164

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

165

POSS with eight imidazolium iodide arms for efficient solid-state dye-sensitized solar cells.  

Science.gov (United States)

Polyhedral oligomeric silsesquioxane functionalized with eight imidazolium iodide arms has been designed and synthesized for use as solid-state electrolytes in solid-state dye-sensitized solar cells, which exhibits a power conversion efficiency of 7.11% under one sun illumination and good long-term stability under one sun soaking. PMID:24394690

Zhang, Wei; Li, Juan; Jiang, Shenghui; Wang, Zhong-Sheng

2014-02-18

166

Scanning ARM Cloud Radar Handbook  

Energy Technology Data Exchange (ETDEWEB)

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-SACR). There are two SACRs on a single pedestal at each site where SACRs are deployed. The selection of the operating frequencies at each deployed site is predominantly determined by atmospheric attenuation at the site. Because RF attenuation increases with atmospheric water vapor content, ARM's Tropical Western Pacific (TWP) sites use the X-/Ka-band frequency pair. The Southern Great Plains (SGP) and North Slope of Alaska (NSA) sites field the Ka-/W-band frequency pair. One ARM Mobile Facility (AMF1) has a Ka/W-SACR and the other (AMF2) has a X/Ka-SACR.

Widener, K; Bharadwaj, N; Johnson, K

2012-06-18

167

Conventional arms transfers: Exporting security or arming adversaries  

Energy Technology Data Exchange (ETDEWEB)

This study examines the dichotomy in the U.S. response to conventional and unconventional arms proliferation. With the end of the cold war, however, this has begun to change. While the spread of NBC munitions continues to be seen as an especially significant peril, many policymakers now view conventional arms transfers as a similar problem, with a comparable requirement for international controls. But a consistent policy and strategy has been difficult to develop because of competing pressures and demands: on one hand, there is a pressure to follow through on pledges to establish international controls on conventional arms traffic; on the other, is pressure to preserve long-standing military relationships with friendly foreign governments. The author maintains that the United States cannot pursue both objectives and expect to accomplish its stated policy goals of regional stability in the world where loyalties and alliances are breaking down and in which every nation is scrambling to advance its own national interests. He concludes that in today's uncertain and chaotic world, it is safer to view most arms transfers as a potential proliferation risk rather than as an assured asset for U.S. national security.

Klare, M.T.

1992-03-19

168

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 benefits, we developed a passive dynamic walking model with free-swinging arms. Even with no torques driving the arms or legs, the model produced walking gaits with arm swinging similar to humans. Passiv...

2009-01-01

169

Task driven feedback control of robot arms - A step toward intelligent control  

Science.gov (United States)

The process of connecting task descriptions originating from machine intelligence planning programs to the mechanization of feedback control of robot arms is analyzed. It is shown in this paper that control theories and practices can be extended to a higher level where feedback control of robot arms directly can respond to work space task commands provided that the work space task as a command is given in the form of a closed function of time. A general mathematical procedure using tools from differential geometry is introduced for synthesizing task space motion planning so that the planned motion can be used as a direct input to the robot arm feedback control system to achieve desired robot hand motion. By definition, 'intelligent control' is being manifested through robot performance in the task space relative to task space commands. Thus, the capability of implementing feedback control of robot arms directly driven by appropriate task descriptions in the workspace as commands is a step toward intelligent control.

Bejczy, A. K.; Tarn, T. J.; Li, Z. F.

1986-01-01

170

Arm locking for space-based laser interferometry gravitational wave observatories  

CERN Document Server

Laser frequency stabilization is a critical part of the interferometry measurement system of space-based gravitational wave observatories such as the Laser Interferometer Space Antenna (LISA). Arm locking as a proposed frequency stabilization technique, transfers the stability of the long arm lengths to the laser frequency. The arm locking sensor synthesizes an adequately filtered linear combination of the inter-spacecraft phase measurements to estimate the laser frequency noise, which can be used to control the laser frequency. At the University of Florida we developed the hardware-based University of Florida LISA Interferometer Simulator (UFLIS) to study and verify laser frequency noise reduction and suppression techniques under realistic LISA-like conditions. These conditions include the variable Doppler shifts between the spacecraft, LISA-like signal travel times, optical transponders, realistic laser frequency and timing noise. We review the different types of arm locking sensors and discuss their expect...

Yu, Yinan; Mueller, Guido

2014-01-01

171

Arms Control and National Security.  

Science.gov (United States)

From the Soviet perspective arms control agreements merely hold the United States in check while the Soviets, who don't feel bound by such agreements, obtain military advantages. The United States must move quickly to redress the strategic military balance that now favors the Soviets. We must emphasize areas like space. (RM)

Graham, Daniel O.

1985-01-01

172

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

173

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

174

Control of a flexible robot arm  

Science.gov (United States)

Exact equations of motion of an arm with known parameters were developed and analyzed preparatory to designing control systems for robotic manipulators. The design of an experimental one-link arm for testing control designs is presented.

Schmitz, E.; Cannon, R.

1980-01-01

175

X-Band PLL Synthesizer  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper deals with design and realization of a PLL synthesizer for the microwave X−band. The synthesizer is intended for use as a local oscillator in a K−band downconverter. The design goal was to achieve very low phase noise and spurious free signal with a sufficient power level. For that purpose a low phase noise MMIC VCO was used in phase locked loop. The PLL works at half the output frequency, therefore there is a frequency doubler at the output of the PLL. The ...

Vagner, P.; Kutin, P.

2006-01-01

176

Frequency synthesizers concept to product  

CERN Multimedia

A frequency synthesizer is an electronic system for generating any of a range of frequencies from a single fixed oscillator. They are found in modern devices like radio receivers, mobile phones, and GPS systems. This comprehensive resource offers RF and microwave engineers a thorough overview of both well-established and recently developed frequency synthesizer design techniques. Professionals find expert guidance on all design aspects, including main architectures, key building blocks, and practical circuit implementation. Engineers learn the development process and gain a solid understanding

Chenakin, Alexander

2011-01-01

177

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

178

The problems of counteracting ARM system design  

Science.gov (United States)

Antiradiation or antiradar missiles (ARM) have become a serious threat to military radar. The problems of counteracting ARM system design are addressed, and it is found that both coherent and incoherent interference could cause the angle deviation of the ARM homing section. Formulas for this angle deviation are given.

Shen, Yunchun

1989-04-01

179

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

2009-12-01

180

Phosphorylcholine substituted polyolefins: New syntheses, solution assemblies, and polymer vesicles  

Science.gov (United States)

This thesis describes the synthesis and applications of a new series of amphiphilic homopolymers and copolymers consisting of hydrophobic polyolefin backbone and hydrophilic phosphorylcholine (PC) pendant groups. These polymers are synthesized by ring opening metathesis polymerization (ROMP) of a novel PC- cyclooctene monomer, and copolymerization of various functionalized cyclooctene comonomers. Incorporation of different comonomers into the PC-polyolefin backbone affords copolymers with different functionalities, including crosslinkers, fluorophores, and other reactive groups, that tune the range of applications of these polymers, and their hydrophobic/hydrophilic balance. The amphiphilic nature of PC-polyolefins was exploited in oil-water interfacial assembly, providing robust polymer capsules to encapsulate and deliver nanoparticles to damaged regions of a substrate in a project termed `repair-and-go.' In repair-and-go, a flexible microcapsule filled with a solution of nanoparticles probes an imperfection-riddled substrate as it rolls over the surface. The thin capsule wall allows the nanoparticles to escape the capsules and enter into the cracks, driven in part by favorable interactions between the nanoparticle ligands and the cracked surface (i.e., hydrophobic-hydrophobic interactions). The capsules then continue their transport along the surface, filling more cracks and depositing particles into them. The amphiphilic nature of PC-polyolefins was also exploited in aqueous assembly, forming novel polymer vesicles in water. PC-polyolefin vesicles ranged in size from 50 nm to 30 µm. The mechanical properties of PC-polyolefin vesicles were measured by micropipette aspiration techniques, and found to be more robust than conventional liposomes or polymersomes prepared from block copolymers. PC-polyolefin vesicles have potential use in drug delivery; it was found that the cancer drug doxorubicin could be encapsulated efficiently in PC-polyolefin vesicles. In another application, PC-polyolefins were used as antifouling coatings for ultrafiltration (UF) and reverse osmosis (RO) water purification membranes. These polymers were found to reduce surface fouling in both UF and RO membranes. Finally, PC-substituted ruthenium benzylidene catalysts were synthesized and evaluated for ROMP in water. PC-substituted catalysts proved effective towards productive metathesis of water soluble cyclic olefins including PEG-substituted oxanorbornene.

Kratz, Katrina A.

 
 
 
 
181

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+.

2011-04-01

182

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

International Nuclear Information System (INIS)

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

183

Novel sulfonated poly(ether ether ketone) with pendant benzimidazole groups as a proton exchange membrane for direct methanol fuel cells  

Energy Technology Data Exchange (ETDEWEB)

A series of sulfonated poly(ether ether ketone)s bearing pendant carboxylic acid groups (C-SPEEKs) have been prepared and subsequently react with 1,2-diaminobenzene to obtain sulfonated poly(ether ether ketone)s with pendant benzimidazole groups (BI-SPEEKs). The expected structures of the sulfonated copolymers are confirmed by {sup 1}H NMR. The resulting copolymers all show good thermal and mechanical properties. It should be noted that the introduction of benzimidazole groups into the copolymer improves its thermal and oxidative stability obviously. Meanwhile, compared to C-SPEEK, BI-SPEEK membranes show much lower water uptake and methanol permeability with the same sulfonation degree (DS). In order to study morphological changes of C-SPEEK and BI-SPEEK membranes, hydrophilic domains sizes from an atomic force microscopy (AFM) are investigated. (author)

Zhang, Yang; Shao, Ke; Zhao, Chengji; Zhang, Gang; Li, Hongtao; Fu, Tiezhu; Na, Hui [Alan G MacDiarmid Institute, College of Chemistry, Jilin University, Qianjin Street 2699, Changchun 130012, Jilin (China)

2009-10-20

184

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

185

Method for Synthesizing Indium Phosphide.  

Science.gov (United States)

This invention relates in general to the synthesis of highly pure, crystalline, indium phosphide (InP). In a more particular aspect, this invention concerns itself with a method for synthesizing crystalline InP under pressures of from about 5 to 30 atmosp...

J. A. Adamski

1984-01-01

186

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

187

Fully automated parallel oligonucleotide synthesizer.  

Czech Academy of Sciences Publication Activity Database

. Ro?. 66, ?. 8 (2001), s. 1299-1314. ISSN 0010-0765Výzkumný zám?r: CEZ:AV0Z4055905Klí?ová slova: automated oligonucleotide synthesizerKód oboru RIV: CC - Organická chemieImpakt faktor: 0.778, rok: 2001

Lebl, M.; Burger, Ch.; Ellman, B.; Heiner, D.; Ibrahim, G.; Jones, A.; Nibbe, M.; Thompson, J.; Mudra, Petr; Pokorný, Vít; Poncar, Pavel; Ženíšek, Karel

188

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

Energy Technology Data Exchange (ETDEWEB)

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 Mn{sup 2+}, Fe{sup 2+}, Fe{sup 3+}, Co{sup 2+}, Ni{sup 2+}, Cu{sup 2+}, Zn{sup 2+}, Cd{sup 2+}, Hg{sup 2+}, Pb{sup 2+} and Al{sup 3+} 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 Fe{sup 2+}, Zn{sup 2+}, Cu{sup 2+}, Pb{sup 2+} and Hg{sup 2+}. The results of spectrophotometric titration experiments disclosed the complexation compositions and complex stability constants of the novel ligands with Fe{sup 2+}, Zn{sup 2+}, Cu{sup 2+}, Pb{sup 2+} and Hg{sup 2+} cations. The monoazatetrathia crown ether showed good sensitivity for Cu{sup 2+} with linearity in the range 5.0x10{sup -7}-2.5x10{sup -6} M and detection limit of 1.6x10{sup -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 Cu{sup 2+}.

Ocak, Ummuehan, E-mail: ummuhanocak@yahoo.co [Department of Chemistry, Faculty of Science, Karadeniz Technical University, 61080 Trabzon (Turkey); Ocak, Mirac; Parlayan, Semanur [Department of Chemistry, Faculty of Science, Karadeniz Technical University, 61080 Trabzon (Turkey); Basoglu, Aysel [Bayburt University, Vocational School, Bayburt (Turkey); Caglar, Yasemin; Bahadir, Zekeriyya [Department of Chemistry, Faculty of Science, Karadeniz Technical University, 61080 Trabzon (Turkey)

2011-04-15

189

Hydrogen Production using Nickel Electrocatalysts with Pendant Amines: Ligand Effects on Rates and Overpotentials  

Energy Technology Data Exchange (ETDEWEB)

A Ni-based electrocatalyst for H2 production, [Ni(8PPh2NC6H4Br)2](BF4)2, featuring eight-membered cyclic diphosphine ligands incorporating a single amine base, 1-para-bromo-phenyl-3,7-triphenyl-1-aza-3,7-diphosphacycloheptane (8PPh2NC6H4Br) has been synthesized and characterized. X-ray ?diffraction studies reveal that the cation of [Ni(8PPh2NC6H4Br)2(CH3CN)](BF4)2 has a distorted trigonal bipyramidal geometry. In CH3CN [Ni(8PPh2NC6H4Br)2]2+ is an electrocatalyst for reduction of protons, and it has a maximum turnover frequency for H2 production of 800 s-1 with a 700 mV overpotential (at Ecat/2) when using [(DMF)H]OTf as the acid. Addition of H2O to acidic CH3CN solutions of [Ni(8PPh2NC6H4Br)2]2+ results in an increase of the turnover frequency for H2 production to a maximum of 3,300 s?1 with an overpotential of 760 mV at Ecat/2. Computational studies carried out on [Ni(8PPh2NC6H4Br)2]2+ indicate the observed catalytic rate is limited by formation of non-productive protonated isomers, diverting active catalyst from the catalytic cycle. The results of this research show that proton delivery from the exogenous acid to the correct position on the proton relay of the metal complex is essential for fast H2 production. This research 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, Basic Energy Sciences. Pacific Northwest National Laboratory is operated by Battelle for the U.S. Department of Energy.

Wiese, Stefan; Kilgore, Uriah J.; Ho, Ming-Hsun; Raugei, Simone; DuBois, Daniel L.; Bullock, R. Morris; Helm, Monte L.

2013-11-01

190

Telescopic arm with automatic advance  

International Nuclear Information System (INIS)

By means of the telescopic arm TV cameras, tools or the like can be moved in and out of reactor pressure vessels. For pressure and traction driving element a curved steel band is used which is guided in the central axis of the telescopic arm by means of one adapting element each per telescopic member. On advancing the steel band, which can absorb considerable bending moments, is drawn out of a cartridge with a spool, by meanes of friction rollers. A nozzle-shaped device in front of the cartridge is flattering the steel band before winding it up. The free buckling length of the stell band is never greater than the distance between two adapting elements (part in the shape of a parallelpiped with a slot for guiding the steel band) resp. the length of a telescopic member. (UWI)

1979-01-01

191

Dual arm coordination and control  

Science.gov (United States)

A generalized master/slave technique and experimental results for coordinated control of two arms rigidly grasping an object is described. An interactive program has been developed to allow a user the flexibility to select appropriate control modes for a given experiment. This interface allows for control gain adjustments. The results of several experiments performed on this system to demonstrate its capabilities such as transporting an object with or without induced internal forces and movement of a constrained object are offered. The system is further developed to achieve a so-called shared control mode in which an operator specifies the free motion trajectory for a point on the object of manipulation via a joystick while the autonomous control system is used for coordination and control of the arms.

Hayati, Samad; Tso, Kam; Lee, Thomas

1989-01-01

192

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

Science.gov (United States)

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. PMID:22281944

Xiao, Haihua; Zhou, Dongfang; Liu, Shi; Zheng, Yonghui; Huang, Yubin; Jing, Xiabin

2012-05-01

193

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English 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 dicarb [...] oxylic 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 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.

194

A new strategy for highly efficient single-drop microextraction with a liquid-gas compound pendant drop.  

Science.gov (United States)

Herein, a simple assembly was designed via a capillary and a funnel-like cap to achieve liquid-gas compound pendant drop (CPD) microextraction with great convenience. Due to the increased contact area and adhesion force between the capillary tip and the drop, the proposed method provides considerable flexibility in producing CPDs with different air bubble sizes. Four pesticides were chosen as model analytes to evaluate the proposed method. By using a 1 ?L chlorobenzene droplet containing a 1 ?L air bubble at a stirring rate of 700 rpm, a 70 to 135-fold enrichment of pesticides was obtained within 3.4 minutes. As compared with a typical SDME, the proposed method showed a 2-fold increase of enrichment factors and a 4-fold decrease of extraction time. Improvement of the extraction efficiency could be ascribed to the increased surface area of the droplet, and the thin film phenomena further improved the extraction kinetics through effective agitation. The results indicate that CPD microextraction could serve as a promising sample pretreatment method for automated high-throughput analyses in a wide variety of research areas. PMID:24691490

Xie, Hai-Yang; Yan, Jian; Jahan, Sharmin; Zhong, Ran; Fan, Liu-Yin; Xiao, Hua; Jin, Xin-Qiao; Cao, Cheng-Xi

2014-05-21

195

Arms Race Within Information Ecosystems  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Interacting agents of exploiters and users within an information ecosystem may be regarded both as biological beings and as part of an economic system of infohabitants. A protection system can be implemented as a filter governing the access to assets. Typically we will have a chain of attacks and countermeasures concerning this access to the desired assets. We model this process as an arms race. We base our model on a process model of a protection system based on expos...

Carlsson, Bengt; Gustavsson, Rune

2001-01-01

196

Dual arm master controller concept  

International Nuclear Information System (INIS)

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

1984-01-01

197

Control of flexible robotic arms, 1  

International Nuclear Information System (INIS)

Dynamic characteristics and control methods of a flexible robotic arm of first degree of freedom system are shown based on modelling a flexible arm as an elastic beam. Vibrations of the arm in positioning can be suppressed by the dynamic compensation with consideration of the arm flexibility, which current robotic arms have more or less in manipulating payloads. Subsequently, a control method of a SCARA type of a second degree of freedom system is shown based on the local feedback with variable adaptive gains to suppress vibrations in positioning control. In case of arm collisions against other objects, a control method to recover the state before collision is also shown as an application. The control methods proposed here are not limited to this special type of robotic arms, but also more general cases. (author)

1985-01-01

198

Frequency Synthesizer For Tracking Filter  

Science.gov (United States)

Digital frequency-synthesizing subsystem generates trains of pulses, free of jitter, for use as frequency-control signals in tracking filters. Part of assembly of electronic equipment used to measure vibrations in bearings in rotating machinery. Designed to meet requirements for tracking narrow-band cage-rotation and ball-pass components of vibrations, as discussed in "Frequency-Tracking Error Detector" (MFS-29538) and "Ball-Pass Cage-Modulation Detector" (MFS-29539). Synthesizer includes preset counter, output of which controls signal for ball-pass filter. Input to this preset counter updated every 2 microseconds: responds almost immediately, effectively eliminating relatively long response time (lock-in time) and phase jitter.

Randall, Richard L.

1990-01-01

199

X-Band PLL Synthesizer  

Directory of Open Access Journals (Sweden)

Full Text Available This paper deals with design and realization of a PLL synthesizer for the microwave X−band. The synthesizer is intended for use as a local oscillator in a K−band downconverter. The design goal was to achieve very low phase noise and spurious free signal with a sufficient power level. For that purpose a low phase noise MMIC VCO was used in phase locked loop. The PLL works at half the output frequency, therefore there is a frequency doubler at the output of the PLL. The output signal from the frequency doubler is filtered by a band-pass filter and finally amplified by a single stage amplifier.

P. Kutin

2006-04-01

200

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

Energy Technology Data Exchange (ETDEWEB)

Two new tetraphosphine ligands, PnC-PPh22NPh2 (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 [CoII(L2)(CH3CN)]2+ and [CoII(L3)(CH3CN)]2+, which are reduced with KC8 to afford [CoI(L2)(CH3CN)]1+ and [CoI(L3)(CH3CN)]1+. Protonation of the CoI complexes affords [HCoIII(L2)(CH3CN)]2+ and [HCoIII(L3)(CH3CN)]2+. Reduction of HCoIII results in formation of the analogous CoI complex through H-Co bond cleavage. Under voltammetric conditions, the reduced cobalt hydride reacts rapidly 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 [HCoIII(L2)(CH3CN)]2+, indicating a bimetallic route wherein two cobalt hydride complexes react to form two equiv [CoI(L2)(CH3CN)]1+ and one equiv H2. The cyclic voltammetry of [HCoIII(L2)(CH3CN)]2+, analyzed using digital simulation, is consistent with an ErCrEr reduction mechanism involving reversible acetonitrile dissociation from [HCoII(L2)(CH3CN)]1+. We thank the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences and Biosciences, for support of the initial parts of this study. Current work is supported by 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. Pacific Northwest National Laboratory is operated by Battelle for the U.S. Department of Energy.

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

2013-08-14

 
 
 
 
201

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

202

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 cobalta carbonyl or precursors thereof. The catalyst exhibits excellent activity, stability in air, and produces highly desirable products fractions even with dilute gaseous reactants.

Sapienza, R.S.; Sansone, M.J.; Slegeir, W.A.R.

1984-07-17

203

Determinism in synthesized chaotic waveforms.  

Science.gov (United States)

The output of a linear filter driven by a randomly polarized square wave, when viewed backward in time, is shown to exhibit determinism at all times when embedded in a three-dimensional state space. Combined with previous results establishing exponential divergence equivalent to a positive Lyapunov exponent, this result rigorously shows that such reverse-time synthesized waveforms appear equally to have been produced by a deterministic chaotic system. PMID:18517561

Corron, Ned J; Blakely, Jonathan N; Hayes, Scott T; Pethel, Shawn D

2008-03-01

204

Summary of compliant and multi-arm control at NASA. Langley Research Center  

Science.gov (United States)

The topics are presented in viewgraph form and include the: single arm system, single arm axis system, single arm control systems, single arm hand controller axis system, single arm position axis system, single arm vision axis system, single arm force axis system, multi-arm system, multi-arm axis system, and the dual arm hand control axis system with control signals.

Harrison, Fenton W.

1992-01-01

205

Physiologically driven avian vocal synthesizer  

Science.gov (United States)

In this work, we build an electronic syrinx, i.e., a programmable electronic device capable of integrating biomechanical model equations for the avian vocal organ in order to synthesize song. This vocal prosthesis is controlled by the bird’s neural instructions to respiratory and the syringeal motor systems, thus opening great potential for studying motor control and its modification by sensory feedback mechanisms. Furthermore, a well-functioning subject-controlled vocal prosthesis can lay the foundation for similar devices in humans and thus provide directly health-related data and procedures.

Sitt, Jacobo D.; Arneodo, Ezequiel M.; Goller, Franz; Mindlin, Gabriel B.

2010-03-01

206

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

207

Arms Trade Offsets and Cases of Corruption  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Because of a lack of transparency and the high complexity of administrative processes, arms acquisition is an area with a high risk of corruption. The aim of this paper is: 1) to provide a typology of cases of corruption in compensatory trade agreements, so called arms trade offsets, that have become integral parts of most arms trades; and 2) to analyze tools possessed by government agencies concerned to prevent or detect corruption. Based on an analysis of all major English-speaking newspape...

Peter Platzgummer

2013-01-01

208

Star distribution in the Orion spiral arm  

Energy Technology Data Exchange (ETDEWEB)

The structure of the Orion spiral arm is studied by numerical experiments, assuming that in each direction considered the star distribution along the line of sight is a combination of two Gaussian laws. The corresponding parameters are evaluated for four Milky Way fields; the bimodal laws now fit the observations by the chi/sup 2/ criterion. In the Orion arm the line-of-sight star densities follow asymmetric curves, steeper at the outer edge of the arm.

Basharina, T.S.; Pavlovskaya, E.D.; Filippova, A.A.

1985-01-01

209

Star distribution in the Orion spiral arm  

International Nuclear Information System (INIS)

The structure of the Orion spiral arm is studied by numerical experiments, assuming that in each direction considered the star distribution along the line of sight is a combination of two Gaussian laws. The corresponding parameters are evaluated for four Milky Way fields; the bimodal laws now fit the observations by the chi"2 criterion. In the Orion arm the line-of-sight star densities follow asymmetric curves, steeper at the outer edge of the arm

1985-01-01

210

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 verify if adequate efforts are been put in this area which is of importance to mankind. The relationship between conflict prevention, conflict management and conflict resolution is also discussed s...

Otunba, Ganiyu

2010-01-01

211

Dynamic analysis for robot arm control  

Science.gov (United States)

Explicit state equations provide detailed analytic insight into the dynamic behavior of a robot arm and facilitate the understanding of the control problem. The analytic strength of explicit state equations is exemplified for a given robot arm. In fact, for the quoted example, the explicit and exact state equations involve considerably less computation than the use of the known most efficient general-purpose computational algorithm for robot arm dynamics.

Bejczy, A. K.

1983-01-01

212

Simplified robot arm dynamics for control  

Science.gov (United States)

A brief summary and evaluation is presented on the use of symbolic state equation techniques in order to represent robot arm dynamics with sufficient accuracy for controlling arm motion. The use of homogeneous transformations and the Lagrangian formulation of mechanics offers a convenient frame for the derivation, analysis and simplification of complex robot dynamics equations. It is pointed out that simplified state equations can represent robot arm dynamics with good accuracy.

Bejczy, A. K.; Paul, R. P.

1981-01-01

213

A comprehensive approach to nuclear arms control  

International Nuclear Information System (INIS)

Cold war nuclear arms control was characterized by American Soviet hostility and the limits of verification; the end of the cold war allowed for a more cooperative approach. From this new situation emerged the idea of a new agenda for arms control and of exploring a more comprehensive approach to nuclear arms control. The author posits eight elements for such a comprehensive approach. Though such an approach seems unrealistic today, recent history teaches us to look beyond today's constraints. (author)

2000-09-01

214

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

215

Optimal output fast feedback in two-time scale control of flexible arms  

Science.gov (United States)

Control of lightweight flexible arms moving along predefined paths can be successfully synthesized on the basis of a two-time scale approach. A model following control can be designed for the reduced order slow subsystem. The fast subsystem is a linear system in which the slow variables act as parameters. The flexible fast variables which model the deflections of the arm along the trajectory can be sensed through strain gage measurements. For full state feedback design the derivatives of the deflections need to be estimated. The main contribution of this work is the design of an output feedback controller which includes a fixed order dynamic compensator, based on a recent convergent numerical algorithm for calculating LQ optimal gains. The design procedure is tested by means of simulation results for the one link flexible arm prototype in the laboratory.

Siciliano, B.; Calise, A. J.; Jonnalagadda, V. R. P.

1986-01-01

216

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

2010-01-01

217

Thermodynamic, spectroscopic, and structural studies of complexation of phenol- and pyridine-armed macrocyclic ligands with univalent metal ions  

Energy Technology Data Exchange (ETDEWEB)

Log K, {Delta}H, and {Delta}S values for interactions of a series of pyridinoazacrown ethers each bearing a phenol arm (2-6) and two macrocycles each bearing a pyridine arm (7, 8) with Na{sup +}, K{sup +}, Tl{sup +}, and Ag{sup +} have been determined in absolute methanol at 25{degrees}C by calorimetric titration. In each case, the complex stability has the sequence Na{sup +} < K {sup +} < Tl{sup +} {much_lt} Ag{sup +}. The phenol-armed macrocycles exhibit selectivity of more than 4 orders of magnitude for Ag{sup +} over Na{sup +}, K{sup +}, and Tl{sup +}. Attachment of a pendant phenol arm having various substituents to parent macrocycle 1 increases the binding abilities of the resulting ligands. Substituents on the para position of the phenol arm have an appreciable effect on cation-binding constants. Good Hammett correlations are found by plotting log K values vs {sigma}{sub p} for interactions of five phenol-armed macrocyclic ligands (2-6) with Na{sup +}, K{sup +}, and Tl{sup +}. The complexation has been characterized by means of {sup 1}H NMR and UV-visible spectroscopic, and X-ray crystallographic methods. The study indicates that the phenol OH group of 2-6 is capable of forming an intramolecular hydrogen bond with the macroring nitrogen atom and that the complexation in absolute methanol generally does not deprotonate these phenols. In the crystal structure of the Na{sup +} -3 complex, the Na{sup +} is coordinated to all seven of the donor atoms of the ligand and two Na{sup +} -3 complexes join together to form a dimer. The dimer contains an intermolecular hydrogen bond formed between the phenol hydrogen atom of one ligand and the phenolate group of a centrosymmetrically related ligand and two {pi}-{pi} stacking interactions between the electron-deficient pyridine ring of one molecule and the electron-rich phenol ring of the other. 36 refs., 5 figs., 6 tabs.

Zhang, Xian Xin; Bordunov, A.V.; Dalley, N.K. [Brigham Young Univ., Provo, UT (United States)] [and others

1997-06-04

218

Synthesizing Customized Planners from Specifications  

CERN Multimedia

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

219

Le volontariat armé au sein des milices nationalistes pendant la Guerre civile espagnole, 1936-1939 El voluntariado armado en las milicias nacionalistas durante la Guerra Civil Española  

Directory of Open Access Journals (Sweden)

Full Text Available La guerre civile espagnole fut le fruit d’une conjonction de nombreux éléments, mais il fallut l’échec d’un coup d’État organisé par une partie de l’armée pour la faire éclater. Cette tentative de coup d’État « survient après une phase de politisation des masses sans équivalent antérieur, même pendant la Révolution de 1868 ». Cette politisation massive, alliée à une radicalisation de la vie politique espagnole durant la seconde République, peut expliquer en partie l’engagement de nombreux Esp...

Diego Ségalas

2011-02-01

220

The Use of Bis[4(2-hydroxy-3-methacryloyloxypropoxy)phenyl]sulfide in Preparation of Microspheres with Pendant Amine Groups as a Heavy Metal Sorbent  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Bis[4(2-hydroxy-3-methacryloyloxypropoxy)phenyl]sulfide-based copolymer microspheres with pendant amine groups are shown to be very efficient in removing Cu(II), Zn(II), Cd(II), and Pb(II) ions from aqueous solutions. Bis(4(2-hydroxy-3-methacryloyloxypropoxy)phenyl)sulfide (1mol) and glycidyl methacrylate (1mol) copolymer microspheres have been prepared by suspension-emulsion polymerisation in the presence of pore forming diluents. Amine functions have been introduced into the surface copolym...

2013-01-01

 
 
 
 
221

Changing Nature of the International Arms Market.  

Science.gov (United States)

This paper assesses how the post-Cold War international arms market is changing in revolutionary ways. It begins by describing the impetus for many of the in-progress structural and operational changes now sweeping the international arms market. Next, it ...

A. W. Hull D. R. Markov

1996-01-01

222

Dual-arm manipulators with adaptive control  

Science.gov (United States)

The described and improved multi-arm invention of this application presents three strategies for adaptive control of cooperative multi-arm robots which coordinate control over a common load. In the position-position control strategy, the adaptive controllers ensure that the end-effector positions of both arms track desired trajectories in Cartesian space despite unknown time-varying interaction forces exerted through a load. In the position-hybrid control strategy, the adaptive controller of one arm controls end-effector motions in the free directions and applied forces in the constraint directions; while the adaptive controller of the other arm ensures that the end-effector tracks desired position trajectories. In the hybrid-hybrid control strategy, the adaptive controllers ensure that both end-effectors track reference position trajectories while simultaneously applying desired forces on the load. In all three control strategies, the cross-coupling effects between the arms are treated as disturbances which are compensated for by the adaptive controllers while following desired commands in a common frame of reference. The adaptive controllers do not require the complex mathematical model of the arm dynamics or any knowledge of the arm dynamic parameters or the load parameters such as mass and stiffness. Circuits in the adaptive feedback and feedforward controllers are varied by novel adaptation laws.

Seraji, Homayoun (Inventor)

1991-01-01

223

JPRS report: Arms control, [October 16, 1989  

Energy Technology Data Exchange (ETDEWEB)

This report contains translations of articles and/or broadcasts on arms control. Titles include: Warsaw Pact Military Council Convenes; Kostov Speaks at Disarmament Session; Chemical Weapons Reduction Proposals Welcomed; Fischer Asks for Arms Cuts in UN Speech; India Succeeds in Another `Prithvi` Test Firing; Central Europe Chemical Weapons-Free Zone; Vancouver SUN Urges Chemical Weapons Treaty; and others.

NONE

1989-10-16

224

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.

2006-11-01

225

Arm locking with Doppler estimation errors  

International Nuclear Information System (INIS)

At the University of Florida we developed the University of Florida LISA Interferometer Simulator (UFLIS) in order to study LISA interferometry with hardware in the loop at a system level. One of the proposed laser frequency stabilization techniques in LISA is arm locking. Arm locking uses an adequately filtered linear combination of the LISA arm signals as a frequency reference. We will report about experiments in which we demonstrated arm locking using UFLIS. During these experiments we also discovered a problem associated with the Doppler shift of the return beam. The initial arm locking publications assumed that this Doppler shift can perfectly be subtracted inside the phasemeter or adds an insignificant offset to the sensor signal. However, the remaining Doppler knowledge error will cause a constant change in the laser frequency if unaccounted for. Several ways to circumvent this problem have been identified. We performed detailed simulations and started preliminary experiments to verify the performance of the proposed new controller designs.

2010-05-01

226

AMF-3 ARM Climate Research Facility  

Science.gov (United States)

The U.S. Department of Energy (DOE) provides scientific infrastructure and data archives to the international Arctic research community through a national user facility. (www.arm.gov). A New ARM Climate Research Facility AMF-3 (ARM Mobile Facility 3) will be located on the North Slope of Alaska, at Oliktok Point. The infrastructure at Oliktok will be designed to be mobile and it may be relocated in the future to support other ARM science missions. AMF-3 instruments include: scanning precipitation radar, scanning cloud radar, Raman lidar, eddy correlation flux systems, upgraded ceilometer, Balloon sounding system, AERI, micropulse lidar, millimeter cloud radar along with all the standard metrological measurements. Unmanned Aerial Systems operations and tethered balloons in the Oliktok area will also be supported. Data from these instruments will be placed in the ARM data archives and available to the international research community.

Helsel, F.; Cook, R.; Lucero, D.; Yellowhorse, L.; Zirzow, J.

2013-12-01

227

Anti-satellite weapons, countermeasures, and arms control  

Science.gov (United States)

Anti-satellite weapons, countermeasures, and arms control; MILSATs, ASATs, and national security; ASAT capabilities and countermeasures; ASAT arms control: history; ASAT arms control: options; and a comparative evaluation of ASAT policy options are discussed.

1985-09-01

228

Nonlinear adaptive control of an elastic robotic arm  

Science.gov (United States)

An approach to control of a class of nonlinear flexible robotic systems is presented. For simplicity, a robot arm (PUMA-type) with three rotational joints is considered. The third link is assumed to be elastic. An adaptive torquer control law is derived for controlling the joint angles. This controller includes a dynamic system in the feedback path, requires only joint angle and rate for feedback, and asymptotically decomposes the elastic dynamics into two subsystems representing the transverse vibrations of the elastic link in two orthogonal planes. To damp out the elastic vibration, a force control law using modal feedback is synthesized. The combination of the torque and force control laws accomplishes joint angle control and elastic mode stabilization.

Singh, S. N.

1986-01-01

229

Segmentgürtel mit mehrteiliger Anhängekombination - Ein Frauenschmuckgürtel der Renaissance (Segmented Girdles with a Multi-part Pendant Construction - a Woman´s Decorative Girdle of the Renaissance  

Directory of Open Access Journals (Sweden)

Full Text Available The finds of this study consist of two belts, and a total of 24 fully preserved fragments show a different high number of conserved segments. They were primarily found as scattered finds in the Brandenburg districts Prignitz, Ostprignitz-Ruppin, Havelland, Upper Havel, district Jericho, Oder-Spree district, Dahme-Spreewald, Uckermark and in Berlin at the Mühlendamm/Spree. According to the present analysis, the examined girdles show a typical composition with fas-tenings consisting of oblong one-piece segments with blunt terminals and with a multi-part pendant construction. Based on formal characteristics they can be categorized as female decorative girdles of the type “Segmented girdles with multi-part pendant construction”.Some examples of fully preserved girdles have even been assembled from segments of several different types of manufacture and decorative motifs. This leads to the conclusion that in general these girdles were probably not produced by specialised craftsmen. Another aim of the present analysis was to work out specific characteristics facilitating the distinction of girdle segments from book-clasps. In this respect, the closing construction was of particular relevance. It could be clarified that toggle fastenings with a spade- or mushroom-shaped hole on the fastening sheet can undoubtedly be identified as girdle elements.

Jörg Harder

2010-12-01

230

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

Science.gov (United States)

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. PMID:19261289

Alvarez, Nicolas J; Walker, Lynn M; Anna, Shelley L

2009-05-15

231

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

232

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

233

Adaptive control of dual-arm robots  

Science.gov (United States)

Three strategies for adaptive control of cooperative dual-arm robots are described. In the position-position control strategy, the adaptive controllers ensure that the end-effector positions of both arms track desired trajectories in Cartesian space despite unknown time-varying interaction forces exerted through the load. In the position-hybrid control strategy, the adaptive controller of one arm controls end-effector motions in the free directions and applied forces in the constraint directions, while the adaptive controller of the other arm ensures that the end-effector tracks desired position trajectories. In the hybrid-hybrid control strategy, the adaptive controllers ensure that both end-effectors track reference position trajectories while simultaneously applying desired forces on the load. In all three control strategies, the cross-coupling effects between the arms are treated as disturbances which are rejected by the adaptive controllers while following desired commands in a common frame of reference. The adaptive controllers do not require the complex mathematical model of the arm dynamics or any knowledge of the arm dynamic parameters or the load parameters such as mass and stiffness. The controllers have simple structures and are computationally fast for on-line implementation with high sampling rates.

Seraji, H.

1987-01-01

234

Naval arms control: Tons of options?  

International Nuclear Information System (INIS)

Arms reductions have reached the US Navy, the most arms control averse of the US services, with budget-driven cuts in numbers of ships and personnel, and President Bush's unilateral withdrawal of tactical nuclear weapons. Soviet President Mikhail Gorbachev's rejoinder not only replicated the Bush initiative for naval weapons, but also called for the destruction of all those weapons, many of which would simply be placed in secure storage ashore under Bush's approach. Can formal, negotiated naval arms control agreements be far behind? Post-war history suggests that such naval arms agreements will remain out of reach. But post-war history has been confounded repeatedly by the events of the past three years. There are, in fact, negotiated naval limits that would enhance the predictability of US-Soviet military relations, and smooth the path of the naval retrenchment already underway on both sides. The Bush-Gorbachev reciprocal withdrawals of naval tactical nuclear arms deal with the most urgent and dangerous issue for naval arms control, improve the US Navy's survivability by drastically reducing the nuclear threat, and improve its flexibility by eliminating the security and political issues associated with carrying nuclear arms. It would be highly desirable, however, to formalize and verify these withdrawals, placing withdrawn weapons under jointly monitored, secure control, to preserve options for further cuts in the future

1991-11-01

235

Synthesizing Diamond from Liquid Feedstock  

Science.gov (United States)

A relatively economical method of chemical vapor deposition (CVD) has been developed for synthesizing diamond crystals and films. Unlike prior CVD methods for synthesizing diamond, this method does not require precisely proportioned flows of compressed gas feedstocks or the use of electrical discharges to decompose the feedstocks to obtain free radicals needed for deposition chemical reactions. Instead, the feedstocks used in this method are mixtures of common organic liquids that can be prepared in advance, and decomposition of feedstock vapors is effected simply by heating. The feedstock used in this method is a solution comprising between 90 and 99 weight percent of methanol and the balance of one or more other oxyhydrocarbons that could include ethanol, isopropanol, and/or acetone. This mixture of compounds is chosen so that dissociation of molecules results in the desired proportions of carbon-containing radicals (principally, CH3) and of OH, H, and O radicals. Undesirably, the CVD temperature and pressure conditions thermodynamically favor the growth of graphite over the growth of diamond. The H radicals are desirable because they help to stabilize the growing surface of diamond by shifting the thermodynamic balance toward favoring the growth of diamond. The OH and O radicals are desirable because they preferentially etch graphite and other non-diamond carbon, thereby helping to ensure the net deposition of pure diamond. The non-methanol compounds are included in the solution because (1) methanol contains equal numbers of C and O atoms; (2) an excess of C over O is needed to obtain net deposition of diamond; and (3) the non-methanol molecules contain multiple carbon atoms for each oxygen atom and thus supply the needed excess carbon A typical apparatus used in this method includes a reservoir containing the feedstock liquid and a partially evacuated stainless-steel reaction chamber. The reservoir is connected to the chamber via tubing and a needle valve or other suitable flow controller. When the liquid enters the low-pressure environment inside the chamber, it evaporates to form a vapor mixture of the same chemical composition. In addition to the inlet for the feedstock liquid, the chamber is fitted with an outlet connected to a vacuum pump (not shown) through a throttle valve (also not shown) that is automatically controlled to keep the pressure at or near the required value throughout the deposition process. Inside the chamber, a spiral filament made of tungsten, tantalum, graphite, or other high-melting-temperature material is electrically heated to a temperature >2,000 C high enough to cause dissociation of vapor molecules into the aforementioned radicals. A deposition substrate typically, a diamond-polished silicon wafer about 2.5 cm square is positioned about 2 cm away from the filament. The exact location of the substrate is chosen so that the substrate becomes heated by the filament to a deposition temperature in the approximate range of 800 to 1,000 C.

Tzeng, Yonhua

2005-01-01

236

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

237

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

238

Robot arm dynamic model reduction for control  

Science.gov (United States)

General methods are described by which the mathematical complexities of explicit and exact state equations of robot arms can be reduced to a simplified and compact state equation representation without introducing significant errors into the robot arm dynamic model. The model reduction methods are based on homogeneous coordinates and on the Langrangian algorithm for robot arm dynamics, and utilize matrix, vector and numeric analysis techniques. The derivation of differential vector representation of centripetal and Coriolis forces which has not yet been established in the literature is presented.

Bejczy, A. K.; Lee, S.

1983-01-01

239

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

2012-04-01

240

Syntheses and Functional Properties of Phthalocyanines  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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. El...

2009-01-01

 
 
 
 
241

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.

Guolai Yang

2012-12-01

242

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

243

Armed Conflict as a Public Health Problem  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Armed conflict between warring states and groups within states have been major causes of ill health and mortality for most of human history. Conflict obviously causes deaths and injuries on the battlefield, but also health consequences from the displacement of

King, Gary; Murray, Christopher J. L.; Lopez, Alan D.; Tomijima, Niels; Krug, Etienne

2002-01-01

244

Science team participation in the ARM program  

International Nuclear Information System (INIS)

This progress report discusses the Science Team participation in the Atmospheric Radiation Measurement (ARM) Program for the period of October 31, 1992 to November 1, 1993. This report summarized the research accomplishments of six papers

1994-01-23

245

Arming and firing system for DISTANT RUNNER  

International Nuclear Information System (INIS)

Sandia A and F systems Division 1132 provided arming and firing support for the DISTANT RUNNER Test Program at White Sands Missile Range. This report describes the field support and the firing system that was used

1982-04-28

246

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

247

One regional ARM guide for climatic evaluation  

Energy Technology Data Exchange (ETDEWEB)

One of the early tasks of the Atmospheric Radiation Measurements (ARM) Program is to provide climatic guides for site selection purposes including possible continental, regional, local and on-site locations. The first guide ``A Preliminary ARM Guide for Climatic Evaluations`` provided some climate data on a continental scale; this one is an attempt to show the variability that exists over a region. Kansas was chosen for this particular guide because it satisfies most of the requirements given in the ARM Program Plan, i.e., climatic significance, potential for synergism with other programs and scientific and logistical viability. Kansas has extreme climatic variations, is centrally located, is compatible with other large scale programs (Fife), has good airfields and accommodations to minimize time and effort in planning and operating an ARM site for continuous use and special campaigns.

Brown, R.M.

1990-04-01

248

One regional ARM guide for climatic evaluation  

Energy Technology Data Exchange (ETDEWEB)

One of the early tasks of the Atmospheric Radiation Measurements (ARM) Program is to provide climatic guides for site selection purposes including possible continental, regional, local and on-site locations. The first guide A Preliminary ARM Guide for Climatic Evaluations'' provided some climate data on a continental scale; this one is an attempt to show the variability that exists over a region. Kansas was chosen for this particular guide because it satisfies most of the requirements given in the ARM Program Plan, i.e., climatic significance, potential for synergism with other programs and scientific and logistical viability. Kansas has extreme climatic variations, is centrally located, is compatible with other large scale programs (Fife), has good airfields and accommodations to minimize time and effort in planning and operating an ARM site for continuous use and special campaigns.

Brown, R.M.

1990-04-01

249

Light duty utility arm baseline system description  

Energy Technology Data Exchange (ETDEWEB)

This document describes the configuration of the Light Duty Utility Arm (LDUA) Baseline System. The baseline system is the initial configuration of the LDUA system that will be qualified for hot deployment in Hanford single shell underground storage tanks.

Kiebel, G.R.

1996-02-01

250

Nonlinear feedback control of multiple robot arms  

Science.gov (United States)

Multiple coordinated robot arms are modeled by considering the arms: (1) as closed kinematic chains, and (2) as a force constrained mechanical system working on the same object simultaneously. In both formulations a new dynamic control method is discussed. It is based on a feedback linearization and simultaneous output decoupling technique. Applying a nonlinear feedback and a nonlinear coordinate transformation, the complicated model of the multiple robot arms in either formulation is converted into a linear and output decoupled system. The linear system control theory and optimal control theory are used to design robust controllers in the task space. The first formulation has the advantage of automatically handling the coordination and load distribution among the robot arms. In the second formulation, by choosing a general output equation, researchers can superimpose the position and velocity error feedback with the force-torque error feedback in the task space simultaneously.

Tarn, T. J.; Yun, X.; Bejczy, A. K.

1987-01-01

251

The molecular spiral arms of NGC 6946  

Science.gov (United States)

From CO-12(J=1 to 0) observations at 45 seconds resolution Tacconi and Young (1989) have found evidence for enhancements in both the CO emissivity and the massive star formation efficiency (MSFE) on optical spiral arms of the bright spiral galaxy NGC 6946. In the optically luminous and well-defined spiral arm in the NE quadrant, there are enhancements in both the H2 surface density and MSFE relative to the interarm regions. In contrast, a poorly defined arm in the SW shows no arm-interarm contrast in the MSFE. To further investigate the molecular gas content of these two spiral arms, researchers have made CO-12 J=2 to 1 and 3 to 2 observations with the James Clerk Maxwell Telescope. In the J=2 to 1 line, they made observations of the NE and SW spiral arm and interarm regions in 4 x 9 10 seconds spaced grids (36 points per grid). Because of decreased sensitivity in the J=3 to 2 line, they were limited to mapping the two arm regions in 2 x 3 10 seconds spaced grids (6 points per grid). The centers of each of the grids lie 2.4 minutes to the NE and 2.3 minutes to the SW of the nucleus of NGC 6946. With the CO J=2 to 1 data researchers are able to fully resolve the two observed spiral arms in NGC 6946. In both cases the CO emission is largely confined to the optical spiral arm regions with the peak observed T asteriskA being up to 4 times higher on the spiral arms than in the interarm regions. Researchers are currently estimating massive star formation efficiencies on and off the spiral arms through direct comparison of the CO maps with an H alpha image. They are also comparing the CO J=2 to 1 data with an HI map made at similar resolution. Thus, they will be able to determine structure in all components of the IS on scales of less than 20 inches.

Tacconi, L. J.; Xie, S.

1990-07-01

252

The molecular spiral arms of NGC 6946  

International Nuclear Information System (INIS)

From CO-12(J=1 to 0) observations at 45 seconds resolution Tacconi and Young (1989) have found evidence for enhancements in both the CO emissivity and the massive star formation efficiency (MSFE) on optical spiral arms of the bright spiral galaxy NGC 6946. In the optically luminous and well-defined spiral arm in the NE quadrant, there are enhancements in both the H2 surface density and MSFE relative to the interarm regions. In contrast, a poorly defined arm in the SW shows no arm-interarm contrast in the MSFE. To further investigate the molecular gas content of these two spiral arms, researchers have made CO-12 J=2 to 1 and 3 to 2 observations with the James Clerk Maxwell Telescope. In the J=2 to 1 line, they made observations of the NE and SW spiral arm and interarm regions in 4 x 9 10 seconds spaced grids (36 points per grid). Because of decreased sensitivity in the J=3 to 2 line, they were limited to mapping the two arm regions in 2 x 3 10 seconds spaced grids (6 points per grid). The centers of each of the grids lie 2.4 minutes to the NE and 2.3 minutes to the SW of the nucleus of NGC 6946. With the CO J=2 to 1 data researchers are able to fully resolve the two observed spiral arms in NGC 6946. In both cases the CO emission is largely confined to the optical spiral arm regions with the peak observed T asterisk sub A being up to 4 times higher on the spiral arms than in the interarm regions. Researchers are currently estimating massive star formation efficiencies on and off the spiral arms through direct comparison of the CO maps with an H alpha image. They are also comparing the CO J=2 to 1 data with an HI map made at similar resolution. Thus, they will be able to determine structure in all components of the IS on scales of less than 20 inches

1990-07-01

253

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

254

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

2013-01-01

255

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

Science.gov (United States)

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.

2013-01-01

256

Arms export controls, subsidies and the WTO exemption  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Owing to the WTO exemption that allows governments to subsidise arms exports, the arms trade is one of the few remaining areas of trade where we observe lump-sum and per unit transfers to exports. This paper examines the effect of arms controls, in the form of licensing delays, on the incentives to subsidise arms exports and conversely the effect of the WTO arms trade exemption on the incentives to break arms control agreements. Our main result is that arms controls and free trade commitments...

2003-01-01

257

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

258

Adjustable degradation and drug release of a thermosensitive hydrogel based on a pendant cyclic ether modified poly(?-caprolactone) and poly(ethylene glycol)co-polymer.  

Science.gov (United States)

The convenient and precise fabrication of drug-hydrogel formulations with satisfactory degradability and a well-controlled drug release profile are crucial factors for injectable hydrogel formulations in clinical applications. Here a new injectable thermosensitive hydrogel formed from poly(?-caprolactone) (PCL)-poly(ethylene glycol)-poly(?-caprolactone) amphiphilicco-polymers with 1,4,8-trioxa[4.6]spiro-9-undecanone (TOSUO) moieties incorporated in the poly(?-caprolactone) (PCL)block (PECT) was constructed to provide a route to tailor the degradation and drug release behavior. The effect of hydrophilic cyclic ether moieties on the degradation of and drug release by PECT hydrogels were evaluated in vitro and in vivo. The results indicated that a freeze-dried powder of paclitaxel-loaded PECT nanoparticles rapidly dissolved in water at ambient temperature with slightly shaking and formed a stable injectable in situ drug-hydrogel formulation at body temperature, which is convenient for clinical operations because it avoids the need for pre-quenching or long-term incubation. The paclitaxel distribution was also more quantitative and homogeneous on entrapping paclitaxel in PECT nanoparticles. Further, the small number of pendant cyclic ether groups in PCL could decrease the cystallinity and hydrophobicity and, as a result, the in vitro and in vivo retention time of PECT hydrogels and the release of entrapped paclitaxel could be tuned from a few weeks to months by varying the amount of PTOSUO in the hydrophobic block. Significantly, paclitaxel-loaded PECT nanoparticles and free paclitaxel could be simultaneously released during the in vitro paclitaxel release from PECT hydrogels. A histopathological evaluation indicated that in vivo injected PECT hydrogels produced only a modest inflammatory response. Thus pendant cyclic ether modification of PCL could be an effective way to achieve the desired degradation and drug release profiles of amphiphilicco-polymer thermosensitive hydrogels and PECT hydrogels may be suitable for local drug delivery. PMID:22835677

Wang, Weiwei; Deng, Liandong; Liu, Shasha; Li, Xu; Zhao, Xiumei; Hu, Renjie; Zhang, Jianhua; Han, Haijie; Dong, Anjie

2012-11-01

259

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

260

Synthesis and characterization of three-arm polyamide 6-polyurethane block copolymer by monomer casting process  

International Nuclear Information System (INIS)

Three-arm polyamide 6-polyurethane (PA 6-PU) block copolymers were synthesized using ?-caprolactam as a monomer, caprolactam sodium as a catalyst, and a three-arm carbamyl caprolactam terminated polyurethane (PU) prepolymer as macroactivator. The three-arm PU prepolymer was formed from polyether glycerol (PPG) and diphenyl methane-4,4' diisocyanate (MDI). The block copolymers were obtained using the monomer casting process (MC) of ?-caprolactam at different content of three-arm PU prepolymer (5-20%). In increasing the content of the soft phase, in Fourier transform infrared (FTIR), a displacement was observed in the band at 1637 cm-1, which is assigned to the amide I of polyamide 6 (PA 6) shifted to a higher wavenumber. This suggested an interaction between the amide group of the PA 6 and the urethane group of the PU. The effects of the PU prepolymer content on the mechanical properties of the block copolymers were investigated. The results showed that the impact strength of the block copolymers at 25 oC and -50 oC temperature could be significantly improved. The crystallization and melting behaviors, structure and thermal properties and morphological characteristic of the block copolymers were studied using the different techniques such as differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), dynamic mechanical analysis (DMTA) and scanning electronic microscopy (SEM).

2010-06-01

 
 
 
 
261

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

2013-04-01

262

An arm-first approach to cleavable mikto-arm star polymers by RAFT polymerization.  

Science.gov (United States)

Redox-cleavable mikto-arm star polymers are prepared by an "arm-first" approach involving copolymerization of a dimethacrylate mediated by a mixture of macroRAFT agents. Thus, RAFT copolymerization of the monomers BMA, DMAEMA, and OEGMA, with the disulfide dimethacrylate cross-linker (DSDMA), bis(2-methacryloyl)oxyethyl disulfide, mediated by a 1:1:1 mixture of three macroRAFT agents with markedly different properties [hydrophilic, poly[oligo(ethylene glycol) methacrylate]-P(OEGMA)8-9 ; cationizable, poly[2-(dimethylamino)ethyl methacrylate]-P(DMAEMA); hydrophobic, poly(n-butyl methacrylate)-P(BMA)] provides low dispersity mikto-arm star polymers. Good control (? < 1.3) is observed for the target P(DMAEMA)/P(OEGMA)/P(BMA) (3:3:1) mikto-arm star, a double hydrophilic P(DMAEMA)/P(OEGMA) (3:3) mikto-arm star and a hydrophobic P(BMA) homo-arm star. However, ? for the target mikto-arm stars increases with an increase in either the ratio [DSDMA]:[total macroRAFT] or the fraction of hydrophobic P(BMA) macroRAFT agent. The quaternized mikto-arm star in dilute aqueous solution shows a monomodal particle size distribution and an average size of ?145 nm. PMID:24504709

Wei, Xiaohu; Moad, Graeme; Muir, Benjamin W; Rizzardo, Ezio; Rosselgong, Julien; Yang, Wantai; Thang, San H

2014-04-01

263

Spiral Arm Morphology of Nearby Galaxies  

Science.gov (United States)

We analyze the spiral structure of 1725 nearby spiral galaxies with redshift less than 0.02. We use the color images provided by the Sloan Digital Sky Survey. We determine the arm classes (grand design, multiple-arm, flocculent) and the broad Hubble types (early, intermediate, late) as well as the bar types (SA, SAB, SB) by visual inspection. We find that flocculent galaxies are mostly of late Hubble type while multiple-arm galaxies are likely to be of early Hubble type. The fractional distribution of grand design galaxies is nearly constant along the Hubble type. The dependence of arm class on bar type is not as strong as that of the Hubble type. However, there is about a three times larger fraction of grand design spirals in SB galaxies than in SA galaxies, with nearly constant fractions of multiple-arm galaxies. However, if we consider the Hubble type and bar type together, grand design spirals are more frequent in early types than in late types for SA and SAB galaxies, while they are almost constant along the Hubble type for SB galaxies. There are clear correlations between spiral structures and the local background density: strongly barred, early-type, grand design spirals favor high-density regions, while non-barred, late-type, flocculent galaxies are likely to be found in low-density regions.

Ann, Hong Bae; Lee, Hyun-Rok

2013-06-01

264

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 1H and 13C 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, Mehmet; Ozcan, Levent; Karabacak, Mehmet; Erol, Ibrahim

2013-07-01

265

Stratagies in synthesizing short-lived radiopharmaceuticals for PET  

International Nuclear Information System (INIS)

Positron Emission Tomography (PET) is one of the most exciting medical imaging modalities and it provides quantitative three dimensional images of specific biochemical, physiological and pathophysiological processes in living human organs like Brain, Heart etc. PET uses short lived radiopharmaceuticals synthesized in situ. Considering the short half lives of the radionuclides (11C-20 min, 18F-110 min, 13N-10 min), the synthesis has to be designed in such a way that the process does not involve any complicated step or long procedures. Since these compounds have to be injected in patients immediately after preparation, extreme precautions have to be taken so that the final product is pure, sterile and apyrogenic. Since a large amount of radioactivity is involved, the synthesis has to be performed in a closed shielded open-quotes Hot Cellclose quotes. The authors have developed a new strategy for the preparation of these compounds using disposable synthetic units. In order to avoid radiation exposure to the operator, they are suggesting the use of a master slave manipulator arm. They routinely prepare several PET compounds based on this technique for clinical and research studies. The final preparations are subjected to sterility and pyrogen testings and found to conform to the USP standard. Radiolabeling of specific drugs for diagnostic purposes is a new and exciting area for chemists who wish to enter the field of medical imaging

1993-08-22

266

Condition Recognition for a Program Synthesizer.  

Science.gov (United States)

An enumeration algorithm which synthesizes programs from example computations is presented. The algorithm, originally proposed by Alan W. Biermann of Duke University, assigns a labelling of the instructions contained in an example trace consistent with pr...

J. S. Lape C. W. Miller

1981-01-01

267

The Trajectory Synthesizer Generalized Profile Interface  

Science.gov (United States)

The Trajectory Synthesizer is a software program that generates aircraft predictions for Air Traffic Management decision support tools. The Trajectory Synthesizer being used by researchers at NASA Ames Research Center was restricted in the number of trajectory types that could be generated. This limitation was not sufficient to support the rapidly changing Air Traffic Management research requirements. The Generalized Profile Interface was developed to address this issue. It provides a flexible approach to describe the constraints applied to trajectory generation and may provide a method for interoperability between trajectory generators. It also supports the request and generation of new types of trajectory profiles not possible with the previous interface to the Trajectory Synthesizer. Other enhancements allow the Trajectory Synthesizer to meet the current and future needs of Air Traffic Management research.

Lee, Alan G.; Bouyssounouse, Xavier; Murphy, James R.

2010-01-01

268

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(hexyloxymethylphthalocyanines, and metal anthraquinocyanines have been synthesized. Then, zinc bis(1,4-didecylbenzo-bis(3,4-pyridoporphyrazines, 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

2009-08-01

269

ARM Cloud Retrieval Ensemble Data Set (ACRED)  

Energy Technology Data Exchange (ETDEWEB)

This document describes a new Atmospheric Radiation Measurement (ARM) data set, the ARM Cloud Retrieval Ensemble Data Set (ACRED), which is created by assembling nine existing ground-based cloud retrievals of ARM measurements from different cloud retrieval algorithms. The current version of ACRED includes an hourly average of nine ground-based retrievals with vertical resolution of 45 m for 512 layers. The techniques used for the nine cloud retrievals are briefly described in this document. This document also outlines the ACRED data availability, variables, and the nine retrieval products. Technical details about the generation of ACRED, such as the methods used for time average and vertical re-grid, are also provided.

Zhao, C; Xie, S; Klein, SA; McCoy, R; Comstock, JM; Delanoë, J; Deng, M; Dunn, M; Hogan, RJ; Jensen, MP; Mace, GG; McFarlane, SA; O’Connor, EJ; Protat, A; Shupe, MD; Turner, D; Wang, Z

2011-09-12

270

Emerging-technology systems and arms control  

Energy Technology Data Exchange (ETDEWEB)

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 previous arms control agreements, these two treaties will have no significant limitations on emerging technology weapons systems. This report examines whether the decision to set aside emerging technology restrictions may undermine the benefits of START and CFE over the lifetimes of these treaties. The United States and the Soviet Union may continue further arms control negotiations after current treaties have been completed. In particular, the two countries committed themselves at the June 1990 Summit to negotiations on a follow-on to START. This report examines how emerging technology systems might influence the approach the United States and the Soviet Union pursue in negotiations toward START II or CFE II treaties.

Lempert, R.; Chang, I.Y.; McCallum, K.

1991-01-01

271

Orion Spiral Arm CAtalogue (OSACA) (Bobylev+, 2006)  

Science.gov (United States)

We transformed radial velocities compiled from more than 1400 published sources, including the Geneva-Copenhagen survey of the solar neighborhood (2004, Nordstrom et al., Cat. ), into a uniform system based on the radial velocities of 854 standard stars in our list (Gontcharov, 2006, Cat. ). This enabled us to calculate the average weighted radial velocities for more than 25000 HIPPARCOS stars located in the local Galactic spiral arm (Orion arm) with a median error of 1km/s. We use these radial velocities together with the stars coordinates, parallaxes, and proper motions to determine their Galactic coordinates and space velocities. These quantities, along with other parameters of the stars, are available from the continuously updated Orion Spiral Arm CAtalogue (OSACA) and the associated database. We perform a kinematic analysis of the stars by applying an Ogorodnikov-Milne model to the OSACA data. The kinematics of the nearest single and multiple main-sequence stars differ substantially. (1 data file).

Bobylev, V. V.; Goncharov, G. A.; Bajkova, A. T.

2007-07-01

272

Spiral arms, comets and terrestrial catastrophism  

International Nuclear Information System (INIS)

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. (author)

1982-01-01

273

Adaptive Control Strategies for Flexible Robotic Arm  

Science.gov (United States)

The control problem of a flexible robotic arm has been investigated. The control strategies that have been developed have a wide application in approaching the general control problem of flexible space structures. The following control strategies have been developed and evaluated: neural self-tuning control algorithm, neural-network-based fuzzy logic control algorithm, and adaptive pole assignment algorithm. All of the above algorithms have been tested through computer simulation. In addition, the hardware implementation of a computer control system that controls the tip position of a flexible arm clamped on a rigid hub mounted directly on the vertical shaft of a dc motor, has been developed. An adaptive pole assignment algorithm has been applied to suppress vibrations of the described physical model of flexible robotic arm and has been successfully tested using this testbed.

Bialasiewicz, Jan T.

1996-01-01

274

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

2012-06-01

275

New Mixer Used in Direct Frequency Synthesizer  

Directory of Open Access Journals (Sweden)

Full Text Available Frequency synthesizers are an essential part of any modern transceiver system. They generate clock and oscillator signals needed for up and down conversion. Today’s communication standards demand both high frequency accuracy and fast frequency settling. The fine frequency resolution, low spurious signals, accuracy and stability are most important for these devices. In this paper, the new frequency synthesizer architecture based on direct synthesis and coincidence mixer is presented. The simulation results are also shown.

Milan Stork

2008-01-01

276

Molecular clouds in the Carina arm  

International Nuclear Information System (INIS)

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"0) in the range 270"0 ? I ? 300"0 and -1"0 ? b ? 1"0, with latitude extensions to cover all Carina arm (I > 280"0) emission beyond the absolute value of b = 1"0. In a concurrent survey every half-degree in latitude and longitude was sampled in the range 270"0 ? I ? 300"0 and -5"0 ? b ? 5"0 at a spatial resolution of 0.5"0. Both surveys had a spectral coverage of 330 km s"-"1 with a resolution of 1.3 km s"-"1. The Carina arm dominates the data. Its abrupt tangent at I ? 280"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_0 = 10 kpc); within R_0 the arm is more difficult to trace in HI than in CO

1986-01-01

277

The quest for the bionic arm.  

Science.gov (United States)

The current state of research of upper extremity prosthetic devices is focused on creating a complete prosthesis with full motor and sensory function that will provide amputees with a near-normal human arm. Although advances are being made rapidly, many hurdles remain to be overcome before a functional, so-called bionic arm is a reality. Acquiring signals via nerve or muscle inputs will require either a reliable wireless device or direct wiring through an osseous-integrated implant. The best way to tap into the "knowledge" present in the peripheral nerve is yet to be determined. PMID:24860130

Hutchinson, Douglas T

2014-06-01

278

Parameter identification for a robotic manipulator arm  

Science.gov (United States)

The development is described of a nonlinear dynamic model for large oscillations of a robotic manipulator arm about a single joint. Optimization routines are formulated and implemented for the identification of electrical and physical parameters from dynamic data taken from an industrial robot arm. Special attention is given to the role of sensitivity in the formulation of robust models of this motion. The importance of actuator effects in the reduction of sensitivity is established and used to develop an electromechanical model of the manipulator system.

Brewer, D. W.; Gibson, J. S.

1985-01-01

279

The arms race and nuclear war  

Energy Technology Data Exchange (ETDEWEB)

Addressing the history, physics, biology, economics, politics, psychology, and ethics of nuclear armaments, the author provides a survey of diverse facets of the nuclear controversy. The study encompasses such key areas as nuclear hardware and technology; the short- and long-term effects of nuclear weapons; strategic doctrine, deterrence and defense policy; the arms race, arms control, and nuclear proliferation; and the economic impact, psychology, and ethics of nuclear armaments. A ''Policy Issues'' section, presenting both the advocate and opponent sides of the debate, is included with each chapter.

Barash, D.P.

1987-01-01

280

Phoenix Robotic Arm connects with `Alice'  

Science.gov (United States)

NASA's Phoenix Mars Lander's Robotic Arm comes into contact with a rock informally named 'Alice' near the 'Snow White' trench. This image was acquired by Phoenix's NASA's Surface Stereo Imager on July 13 during the 48th Martian day, or sol, since Phoenix landed. For scale, the width of the scoop at the end of the arm is about 8.5 centimeters (3.3 inches). The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

2008-01-01

 
 
 
 
281

Generalized bilateral control of robot arms  

Science.gov (United States)

This paper summarizes the theory of a new form of bilateral or force-reflecting manual control of remote robot (slave) arms. The mathematics of workspace representation, command structure, kinematic and dynamic control coordination required for implementing the new form of generalized bilateral control through computer programs is presented. The paper concludes with a brief description of implementation organization of the new system using a six-degree-of-freedom backdrivable hand controller, a PUMA 560 robot arm and a distributed net of microcomputers organized in two groups: one at the remote work site and one at the control station.

Bejczy, A. K.; Lee, S.

1984-01-01

282

Two-Armed, Mobile, Sensate Research Robot  

Science.gov (United States)

The Anthropomorphic Robotic Testbed (ART) is an experimental prototype of a partly anthropomorphic, humanoid-size, mobile robot. The basic ART design concept provides for a combination of two-armed coordination, tactility, stereoscopic vision, mobility with navigation and avoidance of obstacles, and natural-language communication, so that the ART could emulate humans in many activities. The ART could be developed into a variety of highly capable robotic assistants for general or specific applications. There is especially great potential for the development of ART-based robots as substitutes for live-in health-care aides for home-bound persons who are aged, infirm, or physically handicapped; these robots could greatly reduce the cost of home health care and extend the term of independent living. The ART is a fully autonomous and untethered system. It includes a mobile base on which is mounted an extensible torso topped by a head, shoulders, and two arms. All subsystems of the ART are powered by a rechargeable, removable battery pack. The mobile base is a differentially- driven, nonholonomic vehicle capable of a speed >1 m/s and can handle a payload >100 kg. The base can be controlled manually, in forward/backward and/or simultaneous rotational motion, by use of a joystick. Alternatively, the motion of the base can be controlled autonomously by an onboard navigational computer. By retraction or extension of the torso, the head height of the ART can be adjusted from 5 ft (1.5 m) to 6 1/2 ft (2 m), so that the arms can reach either the floor or high shelves, or some ceilings. The arms are symmetrical. Each arm (including the wrist) has a total of six rotary axes like those of the human shoulder, elbow, and wrist joints. The arms are actuated by electric motors in combination with brakes and gas-spring assists on the shoulder and elbow joints. The arms are operated under closed-loop digital control. A receptacle for an end effector is mounted on the tip of the wrist and contains a force-and-torque sensor that provides feedback for force (compliance) control of the arm. The end effector could be a tool or a robot hand, depending on the application.

Engelberger, J. F.; Roberts, W. Nelson; Ryan, David J.; Silverthorne, Andrew

2004-01-01

283

A Stereodynamic Tripodal Ligand with Three Different Coordinating Arms: Synthesis and Zinc(II), Copper(I) Complexation Study  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A tetradentate tripodal ligand containing a chiral center and three different coordinating arms was designed and synthesized. Its complexation properties with ZnII and CuI were studied by NMR and optical spectroscopy. NMR experiments demonstrated the formation of two diastereomers, indicating the stabilization of the central tertiary amine configuration by metal coordination. The inversion of pyramidalization of the central tertiary amine of the ligand was found to be highly dependent upon me...

Liang, Jian; Canary, James W.

2011-01-01

284

An NMR and DFT Investigation on the Conformational Properties of Lanthanide(III) 1,4,7,10-Tetraazacyclododecane-1,4,7,10-tetraacetate Analogues Containing Methylenephosphonate Pendant Arms  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The conformational properties of lanthanide(III) complexes with the mono- and biphosphonate analogues of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetate (DOTA) are investigated by means of density functional theory (DFT) calculations and NMR spectroscopy Geometry optimizations performed at the B3LYP/6-31G(d) level and using a 46 + 4f(n) effective core potential for lanthanides provide two energy minima corresponding to the square-antiprismatic (SAP) and twisted square-antiprismatic (TSAP...

Purgel,, M; Baranyai, Z.; Blas, A.; Rodriguez-blas, T.; Banyai, I.; Platas-iglesias, C.; Toth, I.

2010-01-01

285

Parallelogram mechanisms for mine manipulator arms  

Energy Technology Data Exchange (ETDEWEB)

Kinematic equations are written for the mechanism of a manipulator arm which is used as the operational element of a basic machine and is shaped like a parallelogram. The drive is accomplished using a hydraulic cylinder. A transfer functions method is used to acquire kinematic equations of the final shifts and equations for determining accelerations.

Yoncheva, N.

1983-01-01

286

Clinical applications: Mobile C-arm systems  

International Nuclear Information System (INIS)

The introduction of the image intensifier opened up new perspectives in surgery and interventional radiology. This article traces the development of mobile C-arm systems from the first surgical systems to modern systems such as the BV Pulsera with 3D rotational imaging. (orig.)

2006-01-01

287

Arms and the man - or child  

International Nuclear Information System (INIS)

After almost half a century of remote technology research the telerobotic arm is still less dexterous than the nuclear industry might wish. The authors review R and D in this area of man-machine interfacing, and take a look down the road ahead. (author)

1993-01-01

288

Automation Using Robotic Arm in Rotor Packaging  

Directory of Open Access Journals (Sweden)

Full Text Available Till date automation in small and medium scale industries has not enjoyed the same rate of growth as in other information technology sectors, lagging significantly behind automation in large batch production .The use of LabVIEW interfaced with micro-controller in controlling a robotic arm is a latest technique which is being implemented in this project. In medium scale industries packaging of rotors is done manually. This Process is time consuming and also requires manpower. Through this project our efforts are to increase the efficiency by building an automated system which would employ and also reduces manpower. It involves the use of a robotic arm which would identify the rotors positioning, pick it and then place it in the desired location. With the use of this system the process of packaging can be done effectively without any manpower and also does not require constant monitoring and guidance. The DC gear motors are used in actuating the robotic arm. Electromagnetic gripper is employed at the end of the arm which picks and places the helical rotor of weight 1.5 kg in the desired position for packaging and this mechanism is automated and controlled using LabVIEW. The complete set up is compact and versatile.

GOPU G.

2013-03-01

289

Light duty utility arm software requirements specification  

Energy Technology Data Exchange (ETDEWEB)

This document defines the software requirements for the integrated control and data acquisition system of the Light Duty Utility Arm (LDUA) System. It is intended to be used to guide the design of the application software, to be a basis for assessing the application software design, and to establish what is to be tested in the finished application software product.

Kiebel, G.R.

1995-12-18

290

Molecular Spiral Arms of NGC 6946.  

Science.gov (United States)

From CO-12(J=1 to 0) observations at 45 seconds resolution Tacconi and Young (1989) have found evidence for enhancements in both the CO emissivity and the massive star formation efficiency (MSFE) on optical spiral arms of the bright spiral galaxy NGC 6946...

L. J. Tacconi S. Xie

1990-01-01

291

Vibrations in a moving flexible robot arm  

Science.gov (United States)

The vibration in a flexible robot arm modelled by a moving slender prismatic beam is considered. It is found that the extending and contracting motions have destabilizing and stabilizing effects on the vibratory motions respectively. The vibration analysis is based on a Galerkin approximation with time-dependent basis functions. Typical numerical results are presented to illustrate the qualitative features of vibrations.

Wang, P. K. C.; Wei, Jin-Duo

1987-07-01

292

Irrevocable Multi-Armed Bandit Policies  

CERN Document Server

This paper considers the multi-armed bandit problem with multiple simultaneous arm pulls. We develop a new `irrevocable' heuristic for this problem. In particular, we do not allow recourse to arms that were pulled at some point in the past but then discarded. This irrevocable property is highly desirable from a practical perspective. As a consequence of this property, our heuristic entails a minimum amount of `exploration'. At the same time, we find that the price of irrevocability is limited for a broad useful class of bandits we characterize precisely. This class includes one of the most common applications of the bandit model, namely, bandits whose arms are `coins' of unknown biases. Computational experiments with a generative family of large scale problems within this class indicate losses of up to 5 to 10% relative to an upper bound on the performance of an optimal policy with no restrictions on exploration. We also provide a worst-case theoretical analysis that shows that for this class of bandit proble...

Farias, Vivek

2008-01-01

293

Armed Forces Health Professions Scholarship Program.  

Science.gov (United States)

The Directive reissues Department of Defense (DoD) Directive 1215.14, October 5, 1972, to update DoD policies governing the Armed Forces Health Professions Scholarship Program, established under the provisions of Section 2.(a) of the Uniformed Services He...

K. Howes

1975-01-01

294

Arms Control, Disarmament, and Peace Newsletters.  

Science.gov (United States)

Considers the research value of four types of newsletters on arms control, disarmament, and peace: direct-action, informational, scholarly, and single-issue. An annotated list of 58 newsletters includes those considered most significant of their type and recommended for library collections. (EM)

Atkins, Stephen

1986-01-01

295

Analysis Of Control Of Cooperating Robot Arms  

Science.gov (United States)

Paper presents theoretical analysis of general problem of how to control motions of, and forces exerted by, several multiple-rigid-link robot arms that cooperatively manipulate common rigid object. Emphasis mainly on construction, via full-dynamics approach, of control laws relatively independent of dynamical models.

Kreutz, Kenneth K.; Wen, John Ting-Yung

1991-01-01

296

Arms Control, Deterrence and Nuclear Proliferation Documents  

Science.gov (United States)

This collection contains documents about arms control, nuclear deterrence and nuclear proliferation. Principle documents include: The Baruch Plan, Churchill' s "Iron Curtain" Speech, Eisenhower's Atoms for Peace Speech, Sec. of Defense McNamara's "No Cities" Speech, Sec. of Defense McNamara's "Mutual Deterrence" Speech. The collection also contains documents about recent nuclear events in North Korea, India and Pakistan.

297

STRUCTURED MOLECULAR GAS REVEALS GALACTIC SPIRAL ARMS  

Energy Technology Data Exchange (ETDEWEB)

We explore the development of structures in molecular gas in the Milky Way by applying the analysis of the brightness distribution function and the brightness distribution index (BDI) in the archival data from the Boston University-Five College Radio Astronomy Observatory {sup 13}CO J = 1-0 Galactic Ring Survey. The BDI measures the fractional contribution of spatially confined bright molecular emission over faint emission extended over large areas. This relative quantity is largely independent of the amount of molecular gas and of any conventional, pre-conceived structures, such as cores, clumps, or giant molecular clouds. The structured molecular gas traced by higher BDI is located continuously along the spiral arms in the Milky Way in the longitude-velocity diagram. This clearly indicates that molecular gas changes its structure as it flows through the spiral arms. Although the high-BDI gas generally coincides with H II regions, there is also some high-BDI gas with no/little signature of ongoing star formation. These results support a possible evolutionary sequence in which unstructured, diffuse gas transforms itself into a structured state on encountering the spiral arms, followed by star formation and an eventual return to the unstructured state after the spiral arm passage.

Sawada, Tsuyoshi [Joint ALMA Office, Alonso de Cordova 3107, Vitacura, Santiago 763-0355 (Chile); Hasegawa, Tetsuo [NAOJ Chile Observatory, Joaquin Montero 3000 Oficina 702, Vitacura, Santiago 763-0409 (Chile); Koda, Jin, E-mail: sawada.tsuyoshi@nao.ac.jp [Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794-3800 (United States)

2012-11-01

298

Light duty utility arm software requirements specification  

International Nuclear Information System (INIS)

This document defines the software requirements for the integrated control and data acquisition system of the Light Duty Utility Arm (LDUA) System. It is intended to be used to guide the design of the application software, to be a basis for assessing the application software design, and to establish what is to be tested in the finished application software product

1995-01-01

299

Light Duty Utility Arm Software Test Plan  

International Nuclear Information System (INIS)

This plan describes how validation testing of the software will be implemented for the integrated control and data acquisition system of the Light Duty Utility Arm System (LDUA). The purpose of LDUA software validation testing is to demonstrate and document that the LDUA software meets its software requirements specification

1995-01-01

300

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

 
 
 
 
301

VCO PLL Frequency Synthesizers for Spacecraft Transponders  

Science.gov (United States)

Two documents discuss a breadboard version of advanced transponders that, when fully developed, would be installed on future spacecraft to fly in deep space. These transponders will be required to be capable of operation on any deepspace- communications uplink frequency channel between 7,145 and 7,235 MHz, and any downlink frequency channel between 8,400 and 8,500 MHz. The document focuses on the design and operation of frequency synthesizers for the receiver and transmitter. Heretofore, frequency synthesizers in deep-space transponders have been based on dielectric resonator oscillators (DROs), which do not have the wide tuning bandwidth necessary to tune over all channels in the uplink or downlink frequency bands. To satisfy the requirement for tuning bandwidth, the present frequency synthesizers are based on voltage-controlled-oscillator (VCO) phase-locked loops (PLLs) implemented by use of monolithic microwave integrated circuits (MMICs) implemented using inGaP heterojunction bipolar transistor (HBT) technology. MMIC VCO PLL frequency synthesizers similar to the present ones have been used in commercial and military applications but, until now, have exhibited too much phase noise for use in deep-space transponders. The present frequency synthesizers contain advanced MMIC VCOs, which use HBT technology and have lower levels of flicker (1/f) phase noise. When these MMIC VCOs are used with high-speed MMIC frequency dividers, it becomes possible to obtain the required combination of frequency agility and low phase noise.

Smith, Scott; Mysoor, Narayan; Lux, James; Cook, Brian

2007-01-01

302

Extremal Configuration of Robot Arms in Three Dimensions  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We define a volume function for a robot arms in 3-dimensional Euclidean space and give geometric conditions for its critical points. For 3-arms this volume function is an exact topological Morse function on the 3-sphere.

Siersma, Dirk

2014-01-01

303

Arms control and the Federal Republic of Germany  

Energy Technology Data Exchange (ETDEWEB)

These essays explore the implications of arms control negotiations for the FRG and consider why Germany has traditionally found it impossible to divorce considerations of arms control from their larger political context.

Hanrieder, W.F.

1987-01-01

304

Bibliography on Arms Control Verification: Sixth Update, October 1997.  

Science.gov (United States)

The Bibliography on Arms Control Verification: Sixth Update and its predecessors have been developed to facilitate research on non-proliferation, arms control and disarmament verification issues. With this aim in mind, a Subject Index has been provided to...

1997-01-01

305

Selective chelation of Cd(II) and Pb(II) versus Ca(II) and Zn(II) by using octadentate ligands containing pyridinecarboxylate and pyridyl pendants.  

Science.gov (United States)

Herein we report the coordination properties toward Cd(II), Pb(II), Ca(II), and Zn(II) of a new octadentate ligand (py-H(2)bcpe) based on a ethane-1,2-diamine unit containing two picolinate and two pyridyl pendants, which is structurally derived from the previous reported ligand bcpe. Potentiometric studies have been carried out to determine the protonation constants of the ligand and the stability constants of the complexes with these cations. The introduction of the pyridyl pendants in bcpe provokes a very important increase of the logK(ML) values obtained for the Pb(II) and Cd(II) complexes, while this effect is less important in the case of the Zn(II) analogue. As a result, py-bcpe shows a certain selectivity for Cd(II) and Pb(II) over Zn(II) while keeping good Pb(II)/Ca(II) and Cd(II)/Ca(II) selectivities, and the new receptor py-bcpe can be considered as a new structural framework for the design of novel Cd(II) and Pb(II) extracting agents. Likewise, the stabilities of the Cd(II) and Pb(II) complexes are higher than those of the corresponding EDTA analogues. The X-ray crystal structure of [Zn(py-bcpe)] shows hexadentate binding of the ligand to the metal ion, the coordination polyhedron being best described as a severely distorted octahedron. However, the X-ray crystal structure of the Pb(II) analogue shows octadentate binding of the ligand to the metal ion. A detailed investigation of the structure in aqueous solution of the complexes by using nuclear magnetic resonance (NMR) techniques and density functional theory (DFT) calculations (B3LYP) shows that while in the Zn(II) complex the metal ion is six-coordinated, in the Pb(II) and Ca(II) analogues the metal ions are eight-coordinated. For the Cd(II) complex, our results suggest that in solution the complex exists as a mixture of seven- and eight-coordinated species. DFT calculations performed both in the gas phase and in aqueous solution have been also used to investigate the role of the Pb(II) lone pair in the structure of the [Pb(py-bcpe)] complex. PMID:19877597

Ferreirós-Martínez, Raquel; Esteban-Gómez, David; Platas-Iglesias, Carlos; de Blas, Andrés; Rodríguez-Blas, Teresa

2009-12-01

306

Overview of ARM observations during the ARM MJO Investigation Experiment (AMIE)  

Science.gov (United States)

The US Department of Energy funded Atmospheric Radiation Measurement (ARM) MJO Investigation Experiment (AMIE) was performed in association with the DYNAMO (Dynamics of the Madden-Julian Oscillation) and CINDY-2011 (Cooperative Indian Ocean experiment on intraseasonal variability in the Year 2011) campaigns to study MJO initiation in the Indian Ocean. AMIE included measurements with the second ARM mobile facility (AMF2) on Addu City, the Maldives, and measurements at the permanent ARM site on Manus Island, Papua New Guinea. The dual-pronged nature of the AMIE experiment allowed observation of both MJO convective initiation in the Indian Ocean (at the Maldives site) and the mature phase of the MJO as it passed over the maritime continent (at the Manus site). The AMF2 consists of a full suite of atmospheric instrumentation including surface meteorological instruments, broadband radiometers, microwave radiometers, vertically pointing ceilometer, cloud radar and lidar, scanning cloud radar, and a 2D video disdrometer. At Manus, a similar suite of instruments, including a C-band precipitation radar, is available at the permanent ARM facility. A key aspect of the AMIE deployment was 8/day radiosonde launches at both the Maldives and Manus sites to document the evolution of the thermodynamic structure with the passage of the MJO over the sites. In this presentation, we give an overview of the available ARM thermodynamic, cloud, and precipitation observations during AMIE; show some preliminary ARM value added products; and present some initial comparisons of the ARM and DYNAMO radars.aily cloud frequency observed by the Ka ARM Zenith Radar (KAZR) at the Gan site during AMIE.

McFarlane, S. A.; Long, C. N.; Feng, Z.; Comstock, J. M.; Sivaraman, C.; Bharadwaj, N.; Johnson, K. L.; Orr, B. W.; Ritsche, M.; Collis, S. M.; Schumacher, C.; Ellis, S.; Powell, S.

2012-12-01

307

Kinematic decomposition and classification of octopus arm movements  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The octopus arm is a muscular hydrostat and due to its deformable and highly flexible structure it is capable of a rich repertoire of motor behaviors. Its motor control system uses planning principles and control strategies unique to muscular hydrostats. We previously reconstructed a data set of octopus arm movements from records of natural movements using a sequence of 3D curves describing the virtual backbone of arm configurations. Here we describe a novel representation of octopus arm move...

Zelman, Ido; Titon, Myriam; Yekutieli, Yoram; Hanassy, Shlomi; Hochner, Binyamin; Flash, Tamar

2013-01-01

308

Wireless Control of a Robotic Arm Using Inertial Sensor  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The development of wireless sensing control unit operation is base on wearable inertial sensors. Inertial sensors are of tri axial accelerometer and MEMS. It extends to the control of an anthropomorphic robotic arm. Accelerometers used to measure the orientation and angular velocity of the lower arm. The data processing has been carried out on low cost micro controllers. The movement of the user arm was mimicked by the anthropomorphic robotic arm. The orientation of the control unit is tracke...

2013-01-01

309

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

2011-01-01

310

Dynamics of Non-Steady Spiral Arms in Disk Galaxies  

CERN Document Server

In order to understand the physical mechanisms underlying non-steady stellar spiral arms in disk galaxies, we analyzed the growing and damping phases of their spiral arms using three-dimensional $N$-body simulations. We confirmed that the spiral arms are formed due to a swing amplification mechanism that reinforces density enhancement as a seeded wake. In the damping phase, the Coriolis force exerted on a portion of the arm surpasses the gravitational force that acts to shrink the portion. Consequently, the stars in the portion escape from the arm, and subsequently they form a new arm at a different location. The time-dependent nature of the spiral arms are originated in the continual repetition of this non-linear phenomenon. Since a spiral arm does not rigidly rotate, but follows the galactic differential rotation, the stars in the arm rotate at almost the same rate as the arm. In other words, every single position in the arm can be regarded as the co-rotation point. Due to interaction with their host arms, ...

Baba, Junichi; Wada, Keiichi

2012-01-01

311

Putting the Glare of Publicity on International Arms Sales.  

Science.gov (United States)

Reports on a United Nations committee recommendation that the Security Council establish a universal register of arms. Suggests that such a register would limit the destabilizing influence of major arms sales on developing nations. Argues that visibility of arms sales may help reduce their number. (DK)

Hartman, William

1992-01-01

312

Teaching on Science, Technology and the Nuclear Arms Race.  

Science.gov (United States)

Describes a course focusing on science, technology, and the nuclear arms race. Two sample homework exercises and course topics are provided. Topics, with lists of questions that might be addressed, focus on nuclear weapons, alternatives to deterrence, and arms control. Approaches to teaching about the nuclear arms race are also provided. (JN)

Schroeer, Dietrich

1983-01-01

313

27 CFR 479.193 - Arms Export Control Act.  

Science.gov (United States)

... 2009-04-01 false Arms Export Control Act. 479.193 Section...Applicable § 479.193 Arms Export Control Act. For provisions relating...implements of war, see the Arms Export Control Act (22 U.S.C....

2009-04-01

314

Establishing effective relations between government and its arm’s length bodies requires that they learn to live together  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Central controls have limited the managerial freedoms of both departments and their arm’s length bodies (ALBs). Jill Rutter argues that their relationship needs to be built on mutual trust and respect

Rutter, Jill

2012-01-01

315

Exact solution of the Bellman equation for a ?-discounted reward in a two-armed bandit with switching arms  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We consider the symmetric Poissonian two-armed bandit problem. For the case of switching arms, only one of which creates reward, we solve explicitly the Bellman equation for a ?-discounted reward and prove that a myopic policy is optimal.

1999-01-01

316

Molecular clouds in the Carina arm  

International Nuclear Information System (INIS)

Results from the first large-scale survey in the CO(J = 1 to 0) line of the Vela-Carina-Centaurus region of the Southern Milky Way are reported. The observations, made with the Columbia University 1.2 m millimeter-wave telescope at Cerro Tololo, were spaced every beamwidth (0.125 deg) in the range 270 deg is less than or = l is less than or = 300 deg and -1 deg less than or = b less then or = 1 deg, with latitude extensions to cover all Carina arm emission beyond absolute b = 1 deg. In a concurrent survey made with the same telescope, every half-degree in latitude and longitude was sampled. Both surveys had a spectral coverage of 330 km/s with a resolution of 1.3 km/s. The Carina arm is the dominant feature in the data. Its abrupt tangent at l is approx. = 280 deg and characteristic loop in the l,v diagram are unmistakable evidence for CO spiral structure. When the emission is integrated over velocity and latitude, the height of the step seen in the tangent direction suggests that the arm-interarm contrast is at least 13:1. Comparison of the CO and H I data shows close agreement between these two species in a segment of the arm lying outside the solar circle. The distribution of the molecular layer about the galactic plane in the outer Galaxy is determined. Between R = 10.5 and 12.5 kpc, the average CO midplane dips from z = -48 to -167 pc below the b = 0 deg plane, following a similar well-known warping of the H I layer. In the same range of radii the half-thickness of the CO layer increases from 112 to 182 pc. Between l = 270 deg and 300 deg, 27 molecular clouds are identified and cataloged along with heliocentric distances and masses. An additional 16 clouds beyond 300 deg are cataloged from an adjoining CO survey made with the same telescope. The average mass for the Carina arm clouds is 1.4x 10(6)M (solar), and the average intercloud spacing along the arm is 700 pc

1986-01-01

317

Synthesis of poly(p-phenylene-vinylene) derivatives containing an oxadiazole pendant group and their applications to organic electronic devices.  

Science.gov (United States)

Poly(p-phenylene vinylene) (PPV) derivatives with 2,5-diphenyl-1,3,4-oxadiazole-diyl (OXD) as the side chain, poly[2-{4-[5-(4-(heptyloxy)phenyl)-1,3,4-oxadiazole-2-yI]phenyl-oxy}-1,4-phenylene-vinylene] (OXH-PPV), poly[2-{4-[5-(4-(heptyloxy)phenyl)-1,3,4-oxadia-zole-2-yl]phenyl-oxy}-1,4-phenylenevinylene-co-2-methoxy-5-(2'-ethylhexyloxy)-p-phenylene vinylene] (OXH-PPV-co-MEH-PPV), and poly[2-methoxy-5-(2'-ethylhexyl-oxy)-p-phenylene vinylene] (MEH-PPV), were synthesized via a modified Gilch route. The electron-deficient oxadiazole moiety was introduced on the side chain of the polymer backbone to increase the electron-affinity of the polymers. The electroluminescent (EL) properties of the resulting polymers as an active layer, were investigated by the fabrication of single-layer LEDs and the devices using OXH-PPV-co-MEH-PPV showed better EL properties than those using pure MEH-PPV. Also, to investigate the switching properties of the resulting polymers as an active layer, OFET devices were fabricated in a top-contact/bottom-gate configuration. The resulting FETs exhibited typical p-channel characteristics, field-effect mobility of 6.5 x 10(-4) - 7.0 x 10(-5) cm2 V(-1) s(-1), and on-off ratio of about 10(4)-10(5). PMID:23858852

Lee, Hyemi; Vak, Doojin; Baeg, Kang-Jun; Nah, Yoon-Chae; Kim, Dong-Yu; Noh, Yong-Young

2013-05-01

318

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.

Diane Waku-Kouomou

2007-04-01

319

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

320

Dual-Arm Generalized Compliant Motion With Shared Control  

Science.gov (United States)

Dual-Arm Generalized Compliant Motion (DAGCM) primitive computer program implementing improved unified control scheme for two manipulator arms cooperating in task in which both grasp same object. Provides capabilities for autonomous, teleoperation, and shared control of two robot arms. Unifies cooperative dual-arm control with multi-sensor-based task control and makes complete task-control capability available to higher-level task-planning computer system via large set of input parameters used to describe desired force and position trajectories followed by manipulator arms. Some concepts discussed in "A Generalized-Compliant-Motion Primitive" (NPO-18134).

Backes, Paul G.

1994-01-01

 
 
 
 
321

Reflections upon homosexuality in the armed forces  

Scientific Electronic Library Online (English)

Full Text Available SciELO Social Sciences | Language: English Abstract in english This paper will discuss the issues involved in the incorporation of homosexual personnel into the Armed Forces. From a comparative standpoint it is established that the increasing relevance of this matter in developed countries, is due to social changes, operative necessities and the development of [...] a growing policy from the states towards the generation of maximum levels of equality of opportunities for all individuals, including the Armed Forces. Furthermore, this process can’t be just tackled from a moral point of view, which tends to segregate society and can isolate society from its military institutions. Finally, there exist multiple options to face this topic, since there are not unique "recipes" and therefore, it must be addressed considering the particular features of society.

Claudio, Ortiz Lazo; Sin-Yin Antonela Andreani, Chia.

322

Parametric instabilities in the LCGT arm cavity  

International Nuclear Information System (INIS)

We evaluated the parametric instabilities of LCGT (Japanese interferometric gravitational wave detector project) arm cavity. The number of unstable modes of LCGT is 10-times smaller than that of Advanced LIGO (USA). Since the strength of the instabilities of LCGT depends on the mirror curvature more weakly than that of Advanced LIGO, the requirement of the mirror curvature accuracy is easier to be achieved. The difference in the parametric instabilities between LCGT and Advanced LIGO is because of the thermal noise reduction methods (LCGT, cooling sapphire mirrors; Advanced LIGO, fused silica mirrors with larger laser beams), which are the main strategies of the projects. Elastic Q reduction by the barrel surface (0.2 mm thickness Ta2O5) coating is effective to suppress instabilities in the LCGT arm cavity. Therefore, the cryogenic interferometer is a smart solution for the parametric instabilities in addition to thermal noise and thermal lensing

2008-07-01

323

Implementation of Multilayer AHB Busmatrix for ARM  

Directory of Open Access Journals (Sweden)

Full Text Available The multi-layer AHB busmatrix (ML-AHBbusmatrix proposed by ARM is a highly efficient on chip bus thatallows parallel access paths between multiple masters and slavesin a system. However, the ML-AHB busmatrix of ARM offers onlytransfer-based fixed-priority and round-robin arbitrationschemes. In this paper, we present one way to improve the arbiterimplementation of the ML-AHB busmatrix. The proposed arbiter,which is Self-motivated (SM, selects one of the nine possiblearbitration schemes based upon the priority-level and the desiredtransfer length from the masters so that arbitration leads to themaximum performance.Our SM arbitration scheme has the following advantages: 1 Itcan adjust the processed data unit; 2 it changes the prioritypolicies during runtime; and 3 it is easy to tune the arbitrationscheme according to the characteristics of the target application.

E. Raja

2011-11-01

324

Diversity in the Danish Armed Forces  

DEFF Research Database (Denmark)

The Danish Armed Forces face the functional imperative of becoming a smaller, professional expeditionary force and the societal imperative of including women and ethnic minorities. It currently lags behind its NATO partners in gender and ethnic diversity. Lessons to be learned from NATO members with more diverse militaries, such as the United States, Great Britain, and Canada, include recognition of diversity as a societal imperative to sustain the legitimacy of the armed forces, the necessity of systematically collecting and reporting personnel data to guide policy, the necessity of patience and realistic goals, systematically developing recruitment, development, and retention policies, and the superiority of an all-volunteer force over conscription in fulfilling this societal imperative.

Schaub Jr, Gary John; Pradhan-Blach, Flemming

2012-01-01

325

MAGIC: Marine ARM GPCI Investigation of Clouds  

Energy Technology Data Exchange (ETDEWEB)

The second Atmospheric Radiation Measurement (ARM) Mobile Facility (AMF2) will be deployed aboard the Horizon Lines cargo container ship merchant vessel (M/V) Spirit for MAGIC, the Marine ARM GPCI1 Investigation of Clouds. The Spirit will traverse the route between Los Angeles, California, and Honolulu, Hawaii, from October 2012 through September 2013 (except for a few months in the middle of this time period when the ship will be in dry dock). During this field campaign, AMF2 will observe and characterize the properties of clouds and precipitation, aerosols, and atmospheric radiation; standard meteorological and oceanographic variables; and atmospheric structure. There will also be two intensive observational periods (IOPs), one in January 2013 and one in July 2013, during which more detailed measurements of the atmospheric structure will be made.

Lewis, ER; Wiscombe, WJ; Albrecht, BA; Bland, GL; Flagg, CN; Klein, SA; Kollias, P; Mace, G; Reynolds, RM; Schwartz, SE; Siebesma, AP; Teixeira, J; Wood, R; Zhang, M

2012-10-03

326

ARM Operations Quarterly Report - April - June 2012  

Energy Technology Data Exchange (ETDEWEB)

Individual raw datastreams from instrumentation at the Atmospheric Radiation Measurement (ARM) Climate Research Facility fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real-time. Raw and processed data are then sent approximately daily to the ARM Data Archive, where they are made available to the research community. For each instrument, we calculate the ratio of the actual number of processed data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual datastream, site, and month for the current year and (2) site and fiscal year (FY) dating back to 1998.

Voyles, JW

2012-07-18

327

Embedded Ethernet Controller using ARM LPC2138  

Directory of Open Access Journals (Sweden)

Full Text Available — With the development of network technology and communication technology needs that industrial control can be completed via network has become a trend. Here the proposed system consists of an ARM processor LPC2148 with an external Ethernet interface controller WIZ810MJ and the whole system can function as a web server. In the system the data can be transmitted transparently between host and serial device. The host can communicate with any serial device connected Ethernet without knowing each other’s physical location. Since ARM processor has fast execution capability and Ethernet standard can provide internet access with reasonable speed, this system is suitable for enhancing security in industrial conditions by remotely monitoring various industrial appliances where high safety and care is a necessity. There is no doubt that this system will be useful for a wide variety of industrial applications.

S.P.Magadum

2013-05-01

328

The how and why of arm swing during human walking.  

Science.gov (United States)

Humans walk bipedally, and thus, it is unclear why they swing their arms. In this paper, we will review the mechanisms and functions of arm swinging in human gait. First, we discuss the potential advantages of having swinging arms. Second, we go into the detail on the debate whether arm swing is arising actively or passively, where we will conclude that while a large part of arm swinging is mechanically passive, there is an active contribution of muscles (i.e. an activity that is not merely caused by stretch reflexes). Third, we describe the possible function of the active muscular contribution to arm swinging in normal gait, and discuss the possibility that a Central Pattern Generator (CPG) generates this activity. Fourth, we discuss examples from pathological cases, in which arm swinging is affected. Moreover, using the ideas presented, we suggest ways in which arm swing may be used as a therapeutic aid. We conclude that (1) arm swing should be seen as an integral part of human bipedal gait, arising mostly from passive movements, which are stabilized by active muscle control, which mostly originates from locomotor circuits in the central nervous system (2) arm swinging during normal bipedal gait most likely serves to reduce energy expenditure and (3) arm swinging may be of therapeutic value. PMID:23489950

Meyns, Pieter; Bruijn, Sjoerd M; Duysens, Jacques

2013-09-01

329

Fast complex arm movements in Parkinson's disease.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Fast arm movements involving the shoulder and elbow joints have been analysed in normal controls and in patients with Parkinson's disease. The subjects were requested to draw on a graphic tablet triangles and squares of different size and shape. The patients produced a larger number of EMG burst compared with controls. The movements were accurate, and each segment of the geometric figures was performed with a roughly straight trajectory, but the time necessary to trace the geometric figures a...

1986-01-01

330

Robot-Arm Dynamic Control by Computer  

Science.gov (United States)

Feedforward and feedback schemes linearize responses to control inputs. Method for control of robot arm based on computed nonlinear feedback and state tranformations to linearize system and decouple robot end-effector motions along each of cartesian axes augmented with optimal scheme for correction of errors in workspace. Major new feature of control method is: optimal error-correction loop directly operates on task level and not on joint-servocontrol level.

Bejczy, Antal K.; Tarn, Tzyh J.; Chen, Yilong J.

1987-01-01

331

Swing arm optical CMM for aspherics  

Science.gov (United States)

A profilometer for in situ measurement of the topography of aspheric mirrors called the Swing arm Optical CMM (SOC) was built, and has been used for measuring the figure of 1.4 m convex aspheric mirrors with a performance rivaling full aperture interferometric tests. Errors in the SOC that have odd symmetry are self-calibrated due to the test geometry. Even errors are calibrated against a full aperture interferometric test.

Su, Peng; Oh, Chang Jin; Parks, Robert E.; Burge, James H.

2009-08-01

332

Monitoring and Controlling an Underwater Robotic Arm  

Science.gov (United States)

The SSRMS Module 1 software is part of a system for monitoring an adaptive, closed-loop control of the motions of a robotic arm in NASA s Neutral Buoyancy Laboratory, where buoyancy in a pool of water is used to simulate the weightlessness of outer space. This software is so named because the robot arm is a replica of the Space Shuttle Remote Manipulator System (SSRMS). This software is distributed, running on remote joint processors (RJPs), each of which is mounted in a hydraulic actuator comprising the joint of the robotic arm and communicating with a poolside processor denoted the Direct Control Rack (DCR). Each RJP executes the feedback joint-motion control algorithm for its joint and communicates with the DCR. The DCR receives joint-angular-velocity commands either locally from an operator or remotely from computers that simulate the flight like SSRMS and perform coordinated motion calculations based on hand-controller inputs. The received commands are checked for validity before they are transmitted to the RJPs. The DCR software generates a display of the statuses of the RJPs for the DCR operator and can shut down the hydraulic pump when excessive joint-angle error or failure of a RJP is detected.

Haas, John; Todd, Brian Keith; Woodcock, Larry; Robinson, Fred M.

2009-01-01

333

Tags and seals for arms control verification  

Energy Technology Data Exchange (ETDEWEB)

Tags and seals have long been recognized as important tools in arms control. The trend in control of armaments is to limit militarily significant equipment that is capable of being verified through direct and cooperative means, chiefly on-site inspection or monitoring. Although this paper will focus on the CFE treaty, the role of tags and seals for other treaties will also be addressed. Published technology and concepts will be reviewed, based on open sources. Arms control verification tags are defined as unique identifiers designed to be tamper-revealing; in that respect, seals are similar, being used as indicators of unauthorized access. Tamper-revealing tags might be considered as single-point markers, seals as two-point couplings, and nets as volume containment. The functions of an arms control tag can be considered to be two-fold: to provide field verification of the identity of a treaty-limited item (TLI), and to have a means of authentication of the tag and its tamper-revealing features. Authentication could take place in the field or be completed elsewhere. For CFE, the goal of tags and seals can be to reduce the overall cost of the entire verification system.

DeVolpi, A.

1990-09-18

334

Humanoid Robot Arm Adaptive Control: Experimental Implementation  

Directory of Open Access Journals (Sweden)

Full Text Available In this study, a partially model based adaptive control of humanoid robot arm is presented. The aim of the adaptive control scheme is to deal with the uncertain parameters in its own dynamic model such as link masses or actuators inertias as well as to cope with changing dynamics in the tasks like passing objects between a human and a robot. The main idea here is to derive a dynamic model of the robot’s arm via a software package and parameterized it. Then, employ the adaptive control scheme to identify uncertain parameters such as link masses and actuator inertias online. This scheme will also be suitable for the tasks where robot is lifting weight and or passing an object to a human or vice versa (which is the ultimate goal of this work. The adaptive scheme is simulated and experimentally tested on the Bristol Robotics Laboratory humanoid Bristol- Elumotion-Robot-Torso (BERT Arm. Humanoid BERT robot is developed as a collaboration between Bristol Robotics Laboratory and Elumotion (a Bristol based robotic company.

Said G. Khan

2014-01-01

335

Arms control agency faces uncertain future  

Energy Technology Data Exchange (ETDEWEB)

National security cognoscenti are busy sifting tea leaves trying to puzzle out the fate of arms control and nonproliferation policy in the new Administration. Of special concern to these policy gurus is the future of the semiautonomous Arms Control and Disarmament Agency (ACDA). ACDA's existence as a separate entity on the executive branch's organization chart is precarious. The agency has never functioned as intended since Congress created it in 1961. Its stock over the decades has ebbed and flowed, paralleling the prominence and clout of its director. And except for a few notable successes--the conclusion of the chemical weapons treaty being one--the agency's authority has plummeted in the past 14 years. Today, almost every interested party agrees that something has to be done, that the agency cannot continue as it now functions. Several recent studies have called for its rejuvenation. Still other studies have suggested that ACDA be dismantled, and those activities relevant to national security in a post-Cold War environment be shifted to and integrated into the State Department. Observers expect ACDA to evolve into an agency whose primary focus is on problems of proliferation. In a world in which tighter export controls on dual-use technologies, restraint on arms transfers, and economic assistance conditional on a recipients's security behavior will be the norm for security and stability, a role for ACDA as the U.S.'s nonproliferation nanny is not a bad one.

Ember, L.

1993-02-08

336

Arms control agency faces uncertain future  

International Nuclear Information System (INIS)

National security cognoscenti are busy sifting tea leaves trying to puzzle out the fate of arms control and nonproliferation policy in the new Administration. Of special concern to these policy gurus is the future of the semiautonomous Arms Control and Disarmament Agency (ACDA). ACDA's existence as a separate entity on the executive branch's organization chart is precarious. The agency has never functioned as intended since Congress created it in 1961. Its stock over the decades has ebbed and flowed, paralleling the prominence and clout of its director. And except for a few notable successes--the conclusion of the chemical weapons treaty being one--the agency's authority has plummeted in the past 14 years. Today, almost every interested party agrees that something has to be done, that the agency cannot continue as it now functions. Several recent studies have called for its rejuvenation. Still other studies have suggested that ACDA be dismantled, and those activities relevant to national security in a post-Cold War environment be shifted to and integrated into the State Department. Observers expect ACDA to evolve into an agency whose primary focus is on problems of proliferation. In a world in which tighter export controls on dual-use technologies, restraint on arms transfers, and economic assistance conditional on a recipients's security behavior will be the norm for security and stability, a role for ACDA as the U.S.'s nonproliferation nanny is not a bad one

1993-02-08

337

Synthesis of amphiphilic A3B mikto-arm copolymer from a sugar core :combination of hydrophobic PCL and hydrophilici glycopolymers for biocompatible nanovector preparation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Amphiphilic A3B mikto-arm copolymers have been synthesized using a t-butyl-diphenyl silyl-based methylglucoside derivative. The latter has been first used as initiator for the polymerization of e-caprolactone leading to three-arm star-shaped structures followed by several postpolymerization steps to obtain star-shaped poly(e-caprolactone) macroinitiator. Atom transfer radical polymerization (ATRP) of diisopropylidene galactose methacrylate in THF at 60 °C using CuBr ligated with 1,1,4,7,10,1...

Suriano, Fabian; Coulembier, Olivier; Dubois, Philippe

2010-01-01

338

Argentivorous molecules with two kinds of aromatic side-arms: intramolecular competition between side-arms.  

Science.gov (United States)

Three tetra-armed cyclens with two kinds of side-arms, 3',5'-difluorobenzyl/4'-methylbenzyl, 3',5'-difluorobenzyl/1'-naphthylmethyl, and 3',5'-difluorobenzyl/9'-anthrylmethyl groups, were prepared by reductive amination of 1,7-bis(3',5'-difluorobenzyl)-1,4,7,10-tetraazacyclododecane and the corresponding aromatic aldehydes in the presence of NaBH(OAc)3. The X-ray structures of the Ag(+) complexes and Ag(+)-ion-induced (1)H NMR spectral changes suggest that (i) the chemical shift changes of the protons at the 2'- and 6'-positions in the 3',5'-difluorobenzyl/4'-methylbenzyl side-arms are dependent on the electron density on the adjacent substituted benzenes, and (ii) in the tetra-armed cyclens with 3',5'-difluorobenzyl/1'-naphthylmethyl and 3',5'-difluorobenzyl/9'-anthrylmethyl groups as side-arms, electron-rich aromatic rings preferentially cover the Ag(+) ions incorporated into the ligand cavities, and 3',5'-difluorobenzyl groups do not participate in the Ag(+) interactions. The log K values were estimated using Ag(+)-ion-induced UV-vis spectral changes. PMID:23450225

Habata, Yoichi; Oyama, Yosuke; Ikeda, Mari; Kuwahara, Shunsuke

2013-06-21

339

Maize mitochondria synthesize organ-specific polypeptides  

International Nuclear Information System (INIS)

The authors detected both quantitative and qualitative organ-specific differences in the total protein composition of mitochondria of maize. Labeling of isolated mitochondria from each organ demonstrated that a few protein differences are due to changes in the polypeptides synthesized by the organelle. The synthesis of developmental stage-specific mitochondrial polypeptides was found in the scutella of developing and germinating kernels. The approximately 13-kDa polypeptide synthesized by mitochondria from seedlings of the Texas (T) male-sterile cytoplasm was shown to be constitutively expressed in all organs of line B37T tested. Methomyl, an insecticide known to inhibit the growth of T sterile plants, was shown to be an effective inhibitor of protein synthesis in mitochondria from T plants

1985-01-01

340

Total syntheses of bioactive oxidized ethanolamine phospholipids.  

Science.gov (United States)

[reaction: see text] Truncated ethanolamine phospholipids containing aldehyde functionality, e.g. OVPE, and the corresponding acids, are generated by oxidative cleavage of polyunsaturated phospholipids. To confirm their identities and facilitate studies of the chemistry and biological actions of these analogues of biologically active phosphatidylcholines, e.g. OVPC, total syntheses were developed. An efficient general strategy was used that features selective N-protection of 2-lysophosphatidylethanolamine, and generation of the target compounds by mild deprotection of stable precursors. PMID:12889877

Gugiu, Bogdan G; Salomon, Robert G

2003-08-01

 
 
 
 
341

Mechanical properties of bacterially synthesized nanocellulose hydrogels  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The mechanical characteristics of bacterially synthesized nano-cellulose (BNC) were studied with uniaxial compression and tensile tests. Compressive loads result in a release of water and the deformation of the water-saturated network corresponds approximately to the volume of released water. The BNC hydrogel exhibits a mainly viscous response under compression. The strain response under tensile loads has an elastic and a viscous component. This can be described with a Maxwell model, where th...

Frensemeier, M.; Koplin, C.; Jaeger, R.; Kramer, F.; Klemm, D.

2010-01-01

342

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

2010-12-01

343

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

344

Efficient syntheses of deuterium labelled epinines  

International Nuclear Information System (INIS)

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

345

PZT Powders Synthesized by Hydrothermal Method  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Lead zirconate titanate (PZT) powders with single―phase, cubic morphology and average size of 1 ?m were synthesized using hydrothermal methods. Effects of KOH concentration, hydrothermal treatment time and Pb excess were investigated. The results show that KOH concentration has an important influence on the solid solubility of Pb ion in A―site of PZT perovskite structure. The concentration of Pb2+ vacancies increased with the increase of OH― c...

2012-01-01

346

Magnesioferrite synthesized from magnesian-magnetites  

Directory of Open Access Journals (Sweden)

Full Text Available Magnesioferrite is an important mineral due to its use in different scientific fields and by the fact that the soil through the action of weathering, can be a source of nutrients essential for plant development by the fact that in the soil. Its use in pure form or associated with other minerals is only possible through the synthesis in laboratory conditions. This study aimed to synthesize magnesioferrite and hematite from magnesian-magnetite by a co-precipitation procedure. The methodology used is an adaptation of the method of synthesis of pure magnetite, partially replacing the soluble salts of iron with soluble magnesium salts in the proportion of 30.0 mol% of Fe for Mg. The characterization of the synthetic minerals used x-rays diffraction, total chemical analysis and mass specific magnetic susceptibility. The results showed that besides the magnesian-magnetite an unprecedented muskoxita was synthesized, which upon annealing was converted to magnesioferrite and hematite and in the proportion of 93.1% and 6.9% respectively. The isomorphous substitution of Fe for Mg enhanced the thermal stability of the ferrimagnetic mineral synthesized.

Marcelo Hidemassa Anami

2014-02-01

347

A Synthesizer based on square waves  

CERN Document Server

One of the most widely employed technique for the sound synthesis is based on the Fourier theorem that states that any signal can be obtained as a sum of sinusoids. Unfortunately this algorithm, when applied to synthesizers, requires some peculiar operations, as the addressing of a Look Up Table, that are not easily built-in in standard processors, thus requiring specially designed architectures. The aim of this paper is to show that, when using a new method for the analysis and polar coordinates, a much broader class of functions can be employed as a basis, and it turns out that the square wave is just one of such functions. When the synthesis of signals is carried out by summing square waves, the additive synthesizer architecture results much more simplified, allowing for example to synthesize complex signals simply in software, using general purpose microprocessors, even in real-time. Firstly it will be proven that when using a novel method for the analysis phase, the L2 function space admits a broad class...

Vergara, Sossio

2008-01-01

348

Two-arm master/slave manipulator for nuclear facilities  

International Nuclear Information System (INIS)

Several kinds of one-arm manipulators have been developed for remote maintenance in nuclear facilities to reduce personnel radiation exposure and to keep plant availability as high as possible. In those maintenance tasks, however, there are many that need two arms, e.g., one arm holds the work object and the other arm cuts it with a plasma torch. To answer this need, a dexterous two-arm master/slave manipulator has been developed based on the technology for one-arm manipulators. A prototype two-arm/slave manipulator is shown. The specifications for master and slave manipulators are listed. The prototype two-arm manipulator is undergoing laboratory performance tests. Preliminary results showed the maximum static operating forces were 0.4 N for the all-direct drive (DD)-type arm and 1.1 N for the semi-DD type. The payload for each arm of the slave manipulator was confirmed as 10 kgf, using mock pieces. The decommissioning tasks of cutting pipes and steel plates were successfully carried out

1988-11-04

349

Laser frequency stabilization by dual arm locking for LISA  

International Nuclear Information System (INIS)

The Laser Interferometer Space Antenna (LISA) will be the first dedicated space based gravitational wave detector. LISA will consist of a triangular formation of spacecraft, forming an interferometer with 5x106 km long arms. Annual length variations of the interferometer arms prevent exact laser frequency noise cancellation. Despite prestabilization to an optical cavity the expected frequency noise is many orders of magnitude larger than the required levels. Arm locking is a feedback control method that will further stabilize the laser frequency by referencing it to the 5x106 km arms. Although the original arm locking scheme produced a substantial noise reduction, the technique suffered from slowly decaying start-up transients and excess noise at harmonic frequencies of the inverse round-trip time. Dual arm locking, presented here, improves on the original scheme by combining information from two interferometer arms for feedback control. Compared to conventional arm locking, dual arm locking exhibits significantly reduced start-up transients, no noise amplification at frequencies within the LISA signal band, and more than 50 fold improvement in noise suppression at low frequencies. In this article we present a detailed analysis of the dual arm locking control system and present simulation results showing a noise reduction of 10 000 at a frequency of 10 mHz.

2008-10-15

350

Spiral arm structures revealed in the M31 galaxy  

CERN Document Server

Striking regularities are found in the northwestern arm of the M31 galaxy. Star complexes located in this arm are all spaced 1.2 kpc apart and have similar sizes of about 0.6 kpc. Within the same arm region Beck et al. (1989) detected a regular magnetic field, and we found that its wavelength is the spacing between the complexes. In this arm, groups of HII regions lie inside star complexes, which, in turn, are located inside the gas and dust lane. In contrast, the southwestern arm of M31 splits into a gas and dust lane upstream and a dense stellar arm downstream, with HII regions located mostly along the boundary between these components of the arm. The stellar density in the southwestern arm is much higher than in the northwestern arm, and the former is not fragmented into star complexes. The age gradient across this arm have been found in earlier observations. According the classical SDW theory, these drastic differences may be due due to their different pitch angles: about 0 degree for northwestern part of...

Efremov, Yu N

2009-01-01

351

Synthesis of carbazole-based polymers with 1,3,4-oxadiazole pendant group and their application in organic light-emitting diodes.  

Science.gov (United States)

Structurally well-defined copolymers with high solubility were prepared via palladium-catalyzed polycondensation of N-(2-ethylhexyl)-3,6-dibromocarbazole with 2-aryl-5-(4-aminophenyl)-1,3,4-oxadiazole (aryl = phenyl, p-methylphenyl, p-methoxyphenyl). Copolymers consisted of alkylcarbazole groups in the main chain and 1,3,4-oxadiazole pendants in the side chain. The influence of their aryl substituents on physical, optical, band gaps and electroluminescent characteristics of the copolymers was investigated. Both UV-Visible absorption and photoluminescence emission peaks of the copolymers were similar to each other. The band gap energy of the polymers was measured in the range of 2.84 to approximately 2.88 eV, and HOMO energy in the range of -5.13 to approximately -5.18 eV. These copolymers were used as hole-transporting layers (HTL) in the light-emitting diodes with Alq3 as an emitting layer. Compared to devices with P-H and P-OCH3 used as HTL, it should be noted that device with P-CH3 used as HTL showed higher luminescence. Maximum luminescence of devices was measured to be 276 cd/m2 at 14 V with P-H, 625 cd/m2 at 15 V with P-CH3, and 471 cd/m2 at 14 V with P-OCH3. This might be due to effect of subtle changes in HOMO energy level of polymers with changing substituent groups. Phosphorescent polymer light emitting diodes were also fabricated with an emitting layer consisting of P-CH3 matrix and a red phosphorescent dopant (lr-PIQCH). PMID:19049122

Wang, Hui; Ryu, Jeong-Tak; Cao, Chao; Kwon, Younghwan

2008-09-01

352

Two Pathways for Electrocatalytic Oxidation of Hydrogen by a Nickel Bis(diphosphine) Complex with Pendant Amines in the Second Coordination Sphere  

Energy Technology Data Exchange (ETDEWEB)

A nickel bis(diphosphine) complex containing pendant amines in the second coordination sphere, [Ni(PCy2Nt-Bu2)2](BF4)2 (PCy2Nt-Bu2 = 1,5-di(tert-butyl)-3,7-dicyclohexyl-1,5-diaza-3,7-diphosphacyclooctane), is an electrocatalyst for hydrogen oxidation. Under 1.0 atm H2 using NEt3 as a base and with added water, a turnover frequency of 45 s-1 is observed at 23 °C; this is the fastest observed for a molecular catalyst. The addition of hydrogen to the NiII complex gives thee isomers of the doubly protonated Ni0 complex [Ni(PCy2HNt-Bu2)2](BF4)2; these complexes have been studied by 1H and 31P NMR spectroscopy, and for one isomer, an X-ray diffraction study. Using the pKa values and NiII/I and NiI/0 redox potentials in a thermochemical cycle, the free energy of hydrogen addition to [Ni(PCy2Nt-Bu2)2]2+ was determined to be -7.9 kcal mol-1. The catalytic rate observed in dry acetonitrile for the oxidation of H2 at the NiII/I couple depends on base size, with larger bases (NEt3, tert-BuNH2) resulting in slower catalysis than n-BuNH2. Addition of water accelerates the rate of catalysis, especially for the larger bases. The results of these studies provide important insights into the design of catalysts for hydrogen oxidation that facilitate proton movement and operate at moderate potentials. This research 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. Pacific Northwest National Laboratory is operated by Battelle for the U.S. Department of Energy.

Yang, Jenny Y.; Smith, Stuart E.; Liu, Tianbiao L.; Dougherty, William G.; Hoffert, Wesley A.; Kassel, W. S.; Rakowski DuBois, Mary; DuBois, Daniel L.; Bullock, R. Morris

2013-07-03

353

Magnetic navigation versus mobile C-Arm  

International Nuclear Information System (INIS)

The aim of this study was to demonstrate differences in radiation protection aspects between the use of a digital cardio angiography system with magnetic navigation (Artis Axiom dFcM + Stereotaxis NIOBE (registered) Magnetic Navigation System) and a standard mobile X-ray device with C-arm for electrophysiological procedures. Radiation exposure to staff and patients were analyzed and used for comparison. The time distribution of cardiology procedures for one physician is shown to introduce work of electrophysiology section. The records of procedures were used as information and as a data source for this study. These records include written operation as well as printed exam protocols. This study shows time course of procedures using the electro anatomical mapping system 'CARTO'. A single physicians performance has been used for this comparison to avoid possible differences between operators. The exposure time and air kerma product (PKA) values have been compared for both devices. Median value of exposure time, for each group of 20 patients, was reduced from 27.1 minutes to 20.0 minutes and radiation exposure from 12468 cGycm2 to 9078 cGycm2 PKA values. There is also scattered radiation in the operation area for C-Arm and the new technology presented. Magnetic navigation and replacing C-Arm by cardio angiography system reduces the personal dose by nearly one third, this fact was traced from personal monitoring reports. The main reason for saving time is the necessity to operate the catheter by joystick on a control panel from an adjacent room. These new technologies bring more effectiveness into interventional procedures, especially in cases of complicated examination, and reduce radiation exposure to patients and staff significantly. (author)

2010-05-01

354

Gravitoinertial force level influences arm movement control  

Science.gov (United States)

1. The ability to move the forearm between remembered elbow joint angles immediately after rapid increases or decreases of the background gravitoinertial force (G) level was measured. The movements had been well-practiced in a normal 1G environment before the measurements in high-(1.8G) and low-force (0G) environments. The forearm and upper arm were always unsupported to maximize the influence of altered G-loading and to minimize extraneous cues about arm position. 2. Horizontal and vertical movement planes were studied to measure the effects of varying the G load in the movement plane within a given G background. Rapid and slow movements were studied to assess the role of proprioceptive feedback. 3. G level did not affect the amplitude of rapid movements, indicating that subjects were able to plan and to generate appropriate motor commands for the new G loading of the arm. The amplitude of slow movements was affected by G level, indicating that proprioceptive feedback is influenced by G level. 4. The effects of G level were similar for horizontal and vertical movements, indicating that proprioceptive information from supporting structures, such as the shoulder joint and muscles, had a role in allowing generation of the appropriate motor commands. 5. The incidence and size of dynamic overshoots were greater in 0G and for rapid movements. This G-related change in damping suggests a decrease in muscle spindle activity in 0G. A decrease in muscle spindle activity in 0G and an increase in 1.8G are consistent with the results of our prior studies on the tonic vibration reflex, locomotion, and perception of head movement trajectory in varying force backgrounds.

Fisk, J.; Lackner, J. R.; DiZio, P.

1993-01-01

355

Limitation and reduction of conventional arms  

International Nuclear Information System (INIS)

We are living at a time when war between East and West---not only nuclear but also conventional war--- is totally senseless. It cannot solve any problem---political, economic, or other. From the military point of view, war between East and West is madness. Calculations show that after 20 days of conventional warfare Europe could become another Hiroshima. Therefore we must work out forms of long-term cooperation. Before it is too late, we must radically reduce our military potentials and rethink our military doctrines. The reduction by 500,000 men is for the USSR no simple solution. But that step may become a model for further actions by East and West. The West's proposal that armed forces should be reduced to the level of 95 percent of NATO's armed forces is not a solution. Both sides---the Warsaw Treaty Organization and NATO---must be deprived of the capacity to launch a sudden attack; they must be deprived of their attack potential. The USSR initiative shows the true way toward that goal. What is happening in connection with our decision is not always correctly interpreted in the West, and so I should like to draw attention to some distinctive features of the Soviet armed forces reductions and, first of all, their scale (equivalent to the Bundeswehr of the Federal Republic of Germany). With respect to Europe, Soviet troops are to be reduced in the German Democratic Republic, Czechoslovakia, Hungary, Poland, and the European part of the Soviet Union---a total of 240,000 men, 10,000 tanks, 9,500 artillery systems, and 800 combat aircraft

1989-01-01

356

ARM CLASIC ER2 CRS/EDOP  

Energy Technology Data Exchange (ETDEWEB)

Data was taken with the NASA ER-2 aircraft with the Cloud Radar System and other instruments in conjunction with the DOE ARM CLASIC field campaign. The flights were near the SGP site in north Central Oklahoma and targeted small developing convection. The CRS is a 94 GHz nadir pointing Doppler radar. Also on board the ER-2 was the Cloud Physics Lidar (CPL). Seven science flights were conducted but the weather conditions did not cooperate in that there was neither developing convection, or there was heavy rain.

Gerald Heymsfield

2010-12-20

357

The molecular spiral arms of NGC 6946  

International Nuclear Information System (INIS)

High resolution observations of molecules in external galaxies are essential to understanding physical processes leading to the formation of stars. One question is whether there is a spiral structure in the molecular gas. With the Institute for Radio Astronomy in the Millimeter Range (IRAM) 30 m telescope, researchers are carrying through the mapping of NGC 6946 in the CO-12(1-0) and (2-1) lines. This galaxy is a large, gas-rich Scd spiral with a strong star formation activity. NGC 6946 is well studied at radio and optical wavelengths, so that it is possible to compare the location of the spiral arms tracers: HI ridge, HII regions and molecular clouds. The disk CO emission is very contrasted (no lines for some positions, 1 K in CO(1-0) for some others) and correlated with the optical spiral arms: this clearly shows up in a figure which presents superimposed contours of CO(2-1) integrated emissivity and of H alpha line emission. The agreement is very good, and there is no displacement across the arm between the CO, HI and H alpha ridges of emission. The arms are barely resolved by the 23 inch beam and the molecular contrast averaged over the map is about 4. The CO(2-1) maxima are closer to the position of the HII regions than those of CO(1-0), which could be due to variations of excitation conditions. The CO excitation in the disk of NGC 6946 is low: when all data are convolved to the same resolution of 23 inches the CO(2-1) lines are about 0.45 times fainter than the CO(1-0) ones, while in the nucleus they have roughly the same intensity. This suggests that in the disk of NGC 6946 most of the CO emission comes from cold optically thick gas located in cloud envelopes rather than from cloud cores. The molecular and atomic component in the observed regions of NGC 6946 seems to be organized in large gaseous complexes

1990-07-01

358

ARM mobile facility surface meteorology (MET) handbook.  

Energy Technology Data Exchange (ETDEWEB)

The Atmospheric Radiation Measurement (ARM) Mobile Facility Surface Meteorology station (MET) uses mainly conventional in situ sensors to obtain 1-min statistics of surface wind speed, wind direction, air temperature, relative humidity (RH), barometric pressure, and rainrate. Additional sensors may be added to or removed from the base set of sensors depending upon the deployment location, climate regime, or programmatic needs. In addition, sensor types may change depending upon the climate regime of the deployment. These changes/additions are noted in Section 3.

Ritsche, M. T.; Environmental Science Division

2006-04-01

359

The Illusion of Owning a Third Arm  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Could it be possible that, in the not-so-distant future, we will be able to reshape the human body so as to have extra limbs? A third arm helping us out with the weekly shopping in the local grocery store, or an extra artificial limb assisting a paralysed person? Here we report a perceptual illusion in which a rubber right hand, placed beside the real hand in full view of the participant, is perceived as a supernumerary limb belonging to the participant's own body. This effect was supported b...

Guterstam, Arvid; Petkova, Valeria I.; Ehrsson, H. Henrik

2011-01-01

360

Interstellar extinction in the Perseus arm  

International Nuclear Information System (INIS)

Individual UV extinction curves for nine stars located in the direction of h and chi Persei in the distance range 0.6 to 4.4 kpc are presented. The observations were made with the International Ultraviolet Explorer (IUE) in the low dispersion mode with large aperture. The sample has been enlarged by the use of available UV and visible data for 32 reddened stars with distances r >= 2 kpc located in the same direction. It is found that the mean interstellar extinction curve for the stars located in the Perseus arm shows significantly higher extinction shortward of 2000 A than the galactic mean. (author)

1982-01-01

 
 
 
 
361

Telerobotics with whole arm collision avoidance  

Energy Technology Data Exchange (ETDEWEB)

The complexity of teleorbotic operations in a cluttered environment is exacerbated by the need to present collision information to the operator in an understandable fashion. In addition to preventing movements which will cause collisions, a system providing some form of virtual force reflection (VFR) is desirable. With this goal in mind, Lawrence Livermore National Laboratory (LLNL) has installed a kinematically master/slave system and developed a whole arm collision avoidance system which interacts directly with the telerobotic controller. LLNL has also provided a structure to allow for automated upgrades of workcell models and provide collision avoidance even in a dynamically changing workcell.

Wilhelmsen, K.; Strenn, S.

1993-09-01

362

HS06 Benchmark for an ARM Server  

Science.gov (United States)

We benchmarked an ARM cortex-A9 based server system with a four-core CPU running at 1.1 GHz. The system used Ubuntu 12.04 as operating system and the HEPSPEC 2006 (HS06) benchmarking suite was compiled natively with gcc-4.4 on the system. The benchmark was run for various settings of the relevant gcc compiler options. We did not find significant influence from the compiler options on the benchmark result. The final HS06 benchmark result is 10.4.

Kluth, Stefan

2014-06-01

363

On optimal swinging of the biped arms  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A ballistic walking gait is designed for a planar biped with two identical two-link legs, a trunk and two one-link arms. This seven-link biped is controlled via impulsive torques at the instantaneous double support to obtain a cyclic gait. These impulsive torques are applied in six inter-link joints. Then infinity of solutions exists to find the impulsive torques. An energy cost functional of these impulsive torques is calculated to choose a unique solution by its minimization. Numerical resu...

2008-01-01

364

HS06 Benchmark for an ARM Server  

CERN Document Server

We benchmarked an ARM cortex-A9 based server system with a four-core CPU running at 1.1 GHz. The system used Ubuntu 12.04 as operating system and the HEPSPEC 2006 (HS06) benchmarking suite was compiled natively with gcc-4.4 on the system. The benchmark was run for various settings of the relevant gcc compiler options. We did not find significant influence from the compiler options on the benchmark result. The final HS06 benchmark result is 10.4.

Kluth, Stefan

2013-01-01

365

A real-time EMG-driven virtual arm.  

Science.gov (United States)

An EMG-driven virtual arm is being developed in our laboratories for the purposes of studying neuromuscular control of arm movements. The virtual arm incorporates the major muscles spanning the elbow joint and is used to estimate tension developed by individual muscles based on recorded electromyograms (EMGs). It is able to estimate joint moments and the corresponding virtual movements, which are displayed in real-time on a computer screen. In addition, the virtual arm offers artificial control over a variety of physiological and environmental conditions. The virtual arm can be used to examine how the neuromuscular system compensates for the partial or total loss of a muscle's ability to generate force as might result from trauma or pathology. The purpose of this paper is to describe the design objectives, fundamental components and implementation of our real-time, EMG-driven virtual arm. PMID:11738638

Manal, Kurt; Gonzalez, Roger V; Lloyd, David G; Buchanan, Thomas S

2002-01-01

366

Robot arm system for automatic satellite capture and berthing  

Science.gov (United States)

Load control is one of the most important technologies for capturing and berthing free flying satellites by a space robot arm because free flying satellites have different motion rates. The performance of active compliance control techniques depend on the location of the force sensor and the arm's structural compliance. A compliance control technique for the robot arm's structural elasticity and a consideration for an end-effector appropriate for it are presented in this paper.

Nishida, Shinichiro; Toriu, Hidetoshi; Hayashi, Masato; Kubo, Tomoaki; Miyata, Makoto

1994-01-01

367

A method for removing arm backscatter from EPID images  

International Nuclear Information System (INIS)

Purpose: To develop a method for removing the support arm backscatter from images acquired using current Varian electronic portal imaging devices (EPIDs).Methods: The effect of arm backscatter on EPID images was modeled using a kernel convolution method. The parameters of the model were optimized by comparing on-arm images to off-arm images. The model was used to develop a method to remove the effect of backscatter from measured EPID images. The performance of the backscatter removal method was tested by comparing backscatter corrected on-arm images to measured off-arm images for 17 rectangular fields of different sizes and locations on the imager. The method was also tested using on- and off-arm images from 42 intensity modulated radiotherapy (IMRT) fields.Results: Images generated by the backscatter removal method gave consistently better agreement with off-arm images than images without backscatter correction. For the 17 rectangular fields studied, the root mean square difference of in-plane profiles compared to off-arm profiles was reduced from 1.19% (standard deviation 0.59%) on average without backscatter removal to 0.38% (standard deviation 0.18%) when using the backscatter removal method. When comparing to the off-arm images from the 42 IMRT fields, the mean ? and percentage of pixels with ? < 1 were improved by the backscatter removal method in all but one of the images studied. The mean ? value (1%, 1 mm) for the IMRT fields studied was reduced from 0.80 to 0.57 by using the backscatter removal method, while the mean ? pass rate was increased from 72.2% to 84.6%.Conclusions: A backscatter removal method has been developed to estimate the image acquired by the EPID without any arm backscatter from an image acquired in the presence of arm backscatter. The method has been shown to produce consistently reliable results for a wide range of field sizes and jaw configurations

2013-07-01

368

The crimes of recruiting and using children in armed conflict  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This study is an enquiry into the legal developments aimed at bringing the involvement of children in armed conflict to an end. The issue of children's recruitment into and use by armed groups and forces is addressed from an interdisciplinary legal perspective that combines human rights law, international humanitarian law and international criminal law. The study takes a child rights-based approach to the issue of children in armed conflict and thereby aims to fill some of the current gaps in...

2013-01-01

369

Computer code ARM1 for solving the inverse kinematics of a six-link manipulator arm  

International Nuclear Information System (INIS)

ARM1 is a FORTRAN 77 program for the numerical solutions of the inverse kinematics problems. This paper is a detailed description of the current program (version 1). The code is simple enough for practical use and besides has no particular restrictions except for the specification of memory size. Incorporated checking statements or routine are useful in identifying the accuracies of solutions obtained. (author)

1986-01-01

370

Divergent Total Syntheses of (-)-Aspidospermine and (+)-Spegazzinine  

Science.gov (United States)

Divergent total syntheses of (+)-spegazzinine (1) and (?)-aspidospermine (2) and their extensions to the synthesis of C19-epi-aspidospermine and C3-epi-spegazzinine are detailed, confirming the relative stereochemistry and establishing the absolute configuration of (+)-spegazzinine. A powerful intramolecular [4 + 2]/[3 + 2] cycloaddition cascade of a 1,3,4-oxadiazole provided the pentacyclic skeleton and all the requisite stereochemistry of the natural products in a single reaction that forms three rings, four C–C bonds, and five stereocenters.

Lajiness, James P.; Jiang, Wanlong; Boger, Dale L.

2012-01-01

371

Biocompatibility of poly allylamine synthesized by plasma  

International Nuclear Information System (INIS)

A study of the electric and hydrophilic properties of poly allylamine (PAI) synthesized by plasma whose structure contains N-H, C-H, C-O and O-H bonds is presented, that promote the biocompatibility with the human body. To study the PAI hydrolytic affinity, solutions of salt concentration similar to those of the human body were used. The results indicate that the solutions modify the charge balance in the surfaces reducing the hydrophobicity in the poly allylamine whose contact angle oscillates among 10 and 16 degrees and the liquid-solid surface tension between 4 and 8 dina/cm. (Author)

2007-12-04

372

Monodisperse carbon microspheres synthesized from asphaltene  

International Nuclear Information System (INIS)

Carbon microspheres were synthesized from asphaltene by a chemical vapor deposition (CVD) method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM) and Raman spectroscopy method. The results indicated the monodispersed spheres were almost curving graphitic structure with diameters from 300 to 400 nm. G mode centre of carbon microspheres had shifted upward compared with graphite. As an efficient precursor, asphaltenes were metastable structures at higher temperature. The aromatic carbon rings of asphaltenes promoted the formation of closed cage graphitic structures. The results provide a new perspective for the application of asphaltene

2009-02-15

373

Analog synthesized fast-variable linear load  

Energy Technology Data Exchange (ETDEWEB)

A several kilowatt power level, fast-variable linear resistor has been synthesized by using analog components to control the conductance of power MOSFETs. Risetimes observed have been as short as 500 ns with respect to the control signal and 1 to 2 {mu}s with respect to the power source voltage. A variant configuration of this load that dissipates a constant power set by a control signal is indicated. Replacement of the MOSFETs by SITs to increase power handling, speed and radiation hardness is discussed.

Niedra, J.M. [Sverdrup Technology, Inc., Brook Park, OH (United States). Lewis Research Center Group

1991-07-01

374

Spiral arm structures revealed in the M31 galaxy  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Striking regularities are found in the northwestern arm of the M31 galaxy. Star complexes located in this arm are all spaced 1.2 kpc apart and have similar sizes of about 0.6 kpc. Within the same arm region Beck et al. (1989) detected a regular magnetic field, and we found that its wavelength is the spacing between the complexes. In this arm, groups of HII regions lie inside star complexes, which, in turn, are located inside the gas and dust lane. In contrast, the southweste...

Efremov, Yu N.

2009-01-01

375

Information booklet on personal protective equipment: arm and hand protection  

International Nuclear Information System (INIS)

Fire, heat, cold, electro-magnetic and ionising radiation, electricity, chemicals, impacts, cuts, abrasion, etc. are the common hazards for arms and hands at work. The gloves chosen for protection of the arm and hand should cover those parts adequately and the material of the gloves should be capable of offering protection against the specific hazard involved. Criteria for choosing arm and hand protection equipment will be based on their shape and part of the arm and hand protected. Guide lines for choosing such personal protection equipment for nuclear facilities are given. (M.K.V.). 3 annexures, 1 appendix

1992-01-01

376

Between-Arm Comparisons in Randomized Phase II Trials  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In a phase II trial, we may randomize patients to multiple arms of experimental therapies and evaluate their efficacy to determine if any of them is worth of a large scale phase III trial. Usually the primary objective of such study is to identify experimental therapies that are efficacious compared to a historical control. Each arm is independently evaluated using a standard design for single-arm phase II trial, e.g. Simon’s optimal or minimax design. When more than one arms are accepted t...

2009-01-01

377

Experimental validation of flexible robot arm modeling and control  

Science.gov (United States)

Flexibility is important for high speed, high precision operation of lightweight manipulators. Accurate dynamic modeling of flexible robot arms is needed. Previous work has mostly been based on linear elasticity with prescribed rigid body motions (i.e., no effect of flexible motion on rigid body motion). Little or no experimental validation of dynamic models for flexible arms is available. Experimental results are also limited for flexible arm control. Researchers include the effects of prismatic as well as revolute joints. They investigate the effect of full coupling between the rigid and flexible motions, and of axial shortening, and consider the control of flexible arms using only additional sensors.

Ulsoy, A. Galip

1989-01-01

378

Adaptive control strategies for cooperative dual-arm manipulators  

Science.gov (United States)

Three strategies for adaptive control of cooperative dual-arm robots are discussed. Implementation of these adaptive controllers does not require the use of complex mathematical models of the arm dynamics or knowledge of the arm dynamic parameters or load parameters. These strategies have simple structures, and are computationally fast for on-line implementation with high sampling rates. In all three cases, the coupling effects between the arms through the load are treated as disturbances which are rejected by the adaptive controllers while following desired commands in a common frame of reference. Simulation results demonstrate the usefulness of the controllers.

Seraji, H.

1987-01-01

379

Poly(glycolide multi-arm star polymers: Improved solubility via limited arm length  

Directory of Open Access Journals (Sweden)

Full Text Available Due to the low solubility of poly(glycolic acid (PGA, its use is generally limited to the synthesis of random copolyesters with other hydroxy acids, such as lactic acid, or to applications that permit direct processing from the polymer melt. Insolubility is generally observed for PGA when the degree of polymerization exceeds 20. Here we present a strategy that allows the preparation of PGA-based multi-arm structures which significantly exceed the molecular weight of processable oligomeric linear PGA (<1000 g/mol. This was achieved by the use of a multifunctional hyperbranched polyglycerol (PG macroinitiator and the tin(II-2-ethylhexanoate catalyzed ring-opening polymerization of glycolide in the melt. With this strategy it is possible to combine high molecular weight with good molecular weight control (up to 16,000 g/mol, PDI = 1.4–1.7, resulting in PGA multi-arm star block copolymers containing more than 90 wt % GA. The successful linkage of PGA arms and PG core via this core first/grafting from strategy was confirmed by detailed NMR and SEC characterization. Various PG/glycolide ratios were employed to vary the length of the PGA arms. Besides fluorinated solvents, the materials were soluble in DMF and DMSO up to an average arm length of 12 glycolic acid units. Reduction in the Tg and the melting temperature compared to the homopolymer PGA should lead to simplified processing conditions. The findings contribute to broadening the range of biomedical applications of PGA.

Florian K. Wolf

2010-06-01

380

Europe, arms control and American security  

International Nuclear Information System (INIS)

What has come to be called the Revolution of 1989 has swept away longstanding political and economic arrangements in Eastern Europe. Perhaps more important, it has also called into question the fundamental underpinnings of European security created during the nonpeace that followed World War II. In June 1990, the Warsaw Treaty Organization abandoned the notion that NATO was the ideological enemy. At the same time, NATO ministers agreed at Tunberry, Scotland, to consider defining the Atlantic Alliance as more of a partner of the Soviet Union than as an enemy. The Washington summit of May 1990 between president Mikhail Gorbachev and president George Bush further highlighted the recent changes in the Soviet Union and its former satellites. Issues going to the heart of the viability of the Soviet Union and the communist system of political and economic organization competed with German reunification as central themes. Arms control issues, particularly as they pertain in European military stability, became contingent and dependent on the development of a broader political and economic framework for a new Europe. Whether this framework is viable remains an open question as Gorbachev's role is challenged more and more within the Soviet Union. This paper deals with European arms control issues from the point of view of the United States and its own security interests. The United States involved its security inextricably with that of Western Europe as a conscious decision in the turmoil following World War II

1992-01-01

 
 
 
 
381

High latitude extensions of galactic spiral arms  

International Nuclear Information System (INIS)

The high-z extensions of spiral arms in the Galaxy were investigated observationally and theoretically. High-quality observations, taken by Burton and Soukup, confirmed the existence of the extensions and investigated their properties. Numerical calculations of interstellar gas flow in a tightly wound spiral density wave were performed. The equations were time dependent; the two spatial dimensions were along the streamlines in the galactic plane and perpendicular to the plane. The gravitational potential of the gas was ignored; the flow was driven by the gravitational potential of the stars. The Coriolis force was also ignored, and the flow, calculated in a rectangular coordinate system. The analogy between one-dimensional gas flows into a potential hill (i.e., interarm region) and into a converging-diverging nozzle is discussed in detail to show exactly why and where a shock forms in a spiral arm. Two thermodynamic models of the gas are considered: an isothermal gas and a gas the temperature of which increases with height from the galactic plane. For both models, the resulting flows are in some ways like layered one-dimensional flows: the z velocities are small and the shock fronts are vertical. The shocks extend to much greater distances from the plane than previous hydrostatic work predicted, however, and the shock strength decreases more slowly than expected. The shock at large z should compress the gas to observable densities

1979-01-01

382

Boundary Layer Cloudiness Parameterizations Using ARM Observations  

Energy Technology Data Exchange (ETDEWEB)

This study used DOE ARM data and facilities to: (1) study macroscopic properties of continental stratus clouds at SGP and the factors controlling these properties, (2) develop a scientific basis for understanding the processes responsible for the formation of boundary layer clouds using ARM observations in conjunction with simple parametric models and LES, and (3) evaluate cumulus cloud characteristics retrieved from the MMCR operating at TWP-Nauru. In addition we have used high resolution 94 GHz observations of boundary layer clouds and precipitation to: (1) develop techniques for using high temporal resolution Doppler velocities to study large-eddy circulations and turbulence in boundary layer clouds and estimate the limitations of using current and past MMCR data for boundary layer cloud studies, (2) evaluate the capability and limitations of the current MMCR data for estimating reflectivity, vertical velocities, and spectral under low- signal-to-noise conditions associated with weak no n-precipitating clouds, (3) develop possible sampling modes for the new MMCR processors to allow for adequate sampling of boundary layer clouds, and (4) retrieve updraft and downdraft structures under precipitating conditions.

Bruce Albrecht

2004-09-15

383

Double arm handling device for nuclear reactor  

International Nuclear Information System (INIS)

The invention concerns a machine which, inside a liquid sodium cooled reactor, makes it possible to transfer fuel assemblies forming the core, between the positions that these assemblies fill inside the core to a storage position for these fuel assemblies inside the vessel. These operations are carried out when the reactor plug is in position and when the vessel is filled with liquid sodium, hence they are carried out without being seen. The improved charging system enables the handling time to be cut to a minimum and to diminish the number of positioning operations of the handling system inside the reactor vessel to effect the various charging and discharging operations. It includes a vertically positioned drum of which the top end crosses the plug; a first truck guided in vertical translation by guiding facilities integral with the drum and a second truck guided in vertical translation by other guiding facilities also integral with the drum, each truck being fitted with a horizontal arm at the free end of which is placed a grab hook for holding the fuel assemblies, the guiding facilities being such that the arms remain parallel to each other; gear for moving the trucks vertically and separately; facilities for controlling the opening and closing of the grabs and gear for turning the drum vertically about its centre line

1976-01-01

384

Invariant geometric characteristics of spatial arm motion.  

Science.gov (United States)

This paper examines up to third-order geometric properties of wrist path and the first-order property of wrist trajectory (wrist speed) for spatial pointing movements. Previous studies report conflicting data regarding the time invariance of wrist-path shape, and most analyses are limited to the second-order geometric property (straightness, or strictly speaking, curvature). Subjects performed point-to-point reaching movements between targets whose locations ensured that the wrist paths spanned a range of lengths and lay in various portions of the arm's spatial workspace. Movement kinematics were recorded using electromagnetic sensors located on the subject's arm segments and thorax. Analysis revealed that wrist paths tend to lie in planes and to curve more as movement speed decreases. The orientation of the wrist-path plane depends on the reaching task but does not vary significantly with movement speed. The planarity of wrist paths indicates that the paths have close to zero torsion-a third-order geometric property. Wrist-speed profiles showed multiple peaks for sufficiently slow and long lasting movements, indicating deviation from the well-known, bell-shaped profile. These kinematic findings are discussed in light of various motor control theories. PMID:23771586

Ambike, Satyajit; Schmiedeler, James P

2013-08-01

385

'Raise your arm if you think it makes a difference ! Arms-up versus arms-down position for myocardial perfusion studies  

International Nuclear Information System (INIS)

Full text: The need for myocardial perfusion studies (MPS) using technetium based agents to be performed in the arms-up position has recently been questioned. We have decided to test the hypothesis that studies can be performed in the arms-down position without an increase in the number of perfusion defects demonstrated. MPS were performed in 24 patients in three practice locations for detection of coronary artery disease or assessment of known disease. In each patient either the stress (S) or rest (R) study was performed in both arms-up and arms-down positions. Each study was interpreted blindly by two experienced nuclear medicine physicians (A and B), and each of eight myocardial segments was graded on a five point scale from normal to markedly abnormal. Comparisons were performed for the number and severity of defects between the pairs of studies, and between physician A and B. For simplicity the results have been re-grouped into normal/equivocal and abnormal (mild/moderate/ marked). In conclusion in this pilot study considerable discordance is noted between the arms-up and arms-down studies. Contrary to some reports, our findings indicate that performing MPS in the arms-down position will introduce errors in the reporting process. Copyright (2000) The Australian and New Zealand Society of Nuclear Medicine Inc

2000-09-01

386

Synthesized image processings in the neurosurgical field  

International Nuclear Information System (INIS)

Widespread applications of computed tomography (CT), magnetic resonance imaging (MRI) and other diagnostic imaging modalities using digital techniques have recently created increasing demands for a picture archiving and communicating system (PACS) with efficient image management capabilities. For its introduction into a hospital specializing in neurological surgery, the following three pieces of software for medical image synthesis, have been developed in order to achieve efficient image management in the field of clinical neurosurgery. The field piece of software is for automatically mapping small thalamic or basal ganglionic lesions depicted on MR images onto the Schaltenbrand-Wahren's brain atlas. The second is for superimposing two angiographic films to yield a single synthesized image featuring two different phases simultaneously. The third software is for superimposing sagittal CT images, automatically reconstructed from the axial slices, onto the lateral views of cerebral angiograms. It was found that these PACS-based imaging techniques may offer the potential to help both in anatomical localization of small intracranial lesions using the first piece of software, and in the evaluation of basic hemodynamics, including collateral circulation in a single angiographic image, utilizing the second software. The resulting synthesized images obtained with the use of the third software, were also found useful in simplifying the design of craniotomy for intracranial lesions by graphically indicating their locations, along with cerebral vessels in a lateral view. These newly developed methods for medical image synthesis are described in detail with their clinical applications. (author)

1990-01-01

387

Synthesizing Waves from Animated Height Fields  

DEFF Research Database (Denmark)

Computer animated ocean waves for feature films are typically carefully choreographed to match the vision of the director and to support the telling of the story. The rough shape of these waves is established in the previsualization (previs) stage, where artists use a variety of modeling tools with fast feedback to obtain the desired look. This poses a challenge to the effects artists who must subsequently match the locked-down look of the previs waves with high-quality simulated or synthesized waves, adding the detail necessary for the final shot. We propose a set of automated techniques for synthesizing Fourier-based ocean waves that match a previs input, allowing artists to quickly enhance the input wave animation with additional higher-frequency detail that moves consistently with the coarse waves, tweak the wave shapes to flatten troughs and sharpen peaks if desired (as is characteristic of deep water waves), and compute a physically reasonable velocity field of the water analytically. These properties are demonstrated with several examples, including a previs scene from a visual effects production environment.

Nielsen, Michael Bang; Söderström, Andreas

2013-01-01

388

Language Translator and Synthesizer for Mobile  

Directory of Open Access Journals (Sweden)

Full Text Available The Machine Translation domain of Natural Language Processing and the area of Artificial Intelligence are very useful in providing people with a machine, which understands diverse languages spoken by common people. It presents the user of a computer system with an interface, with which he feels more comfortable. Since, there are many different languages spoken in this world, we are constantly in need for translators to enable people speaking different languages to share ideas and communicate with one another. Human translators are rare to find and are inaccessible to the common man. With the concept of Machine Translation we may work towards achieving the goal using easily available computer systems. Besides, one of the first linguistic applications of computers to be funded was machine translation. The English to Marathi translator designed will be very useful to people who don’t understand English.Speech synthesizer is the artificial production of human speech. A computer system used for this purpose is called a speech synthesizer, and can be implemented in software or hardware.

Mrs.J. P. Kshirsagar, Prof. G. G. Chiddarwar

2012-04-01

389

Hydroquinone-O,O'-diacetic acid ('Q-linker') as a replacement for succinyl and oxalyl linker arms in solid phase oligonucleotide synthesis.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

When hydroquinone-O,Ooffiacetic acid is used as a linker arm in solid phase oligonucleotide synthesis, the time for NH4OH cleavage of oligodeoxy- or oligoribonucleotides is reduced to only 2 min. This allows increased productivity on automated DNA synthesizers without requiring any other modifications to existing reagents or synthesis and deprotection methods. The Q-linker may also be rapidly cleaved by milder reagents such as 5% NH4OH, potassium carbonate, anhydrous ammonia, t-butylamine or ...

Pon, R. T.; Yu, S.

1997-01-01

390

Synthesis and characterization of six-arm star poly(delta-valerolactone)-block-methoxy poly(ethylene glycol) copolymers.  

Science.gov (United States)

Novel amphiphilic six-arm star diblock copolymers based on biocompatible and biodegradable poly(delta-valerolactone) (PVL) and methoxy poly(ethylene glycol) (MePEG) were synthesized by a two-step process. First, the hydrophobic star-shaped PVL with hydroxyl terminated functional groups was synthesized using a multifunctional alcohol, dipentaerythritol (DPE), as the initiator and fumaric acid as the catalyst. The amphiphilic six-arm star copolymer of poly(delta-valerolactone)-b-methoxy poly(ethylene glycol), (PVL-b-MePEG)(6), was then synthesized by coupling the hydroxyl terminated six-arm PVL homopolymer with alpha-methoxy-omega-chloroformate-poly(ethylene glycol) (MePEG-COCl). (1)H NMR and GPC analyses confirmed the successful synthesis of star-shaped copolymers with predicted compositions and narrow molecular weight distributions. DSC analysis revealed that the glass transition temperatures of the star PVL homopolymers with M(n) between 5000 and 49 000 are not dependent on their molecular weights, whereas the melting temperatures of both the PVL homopolymers and the amphiphilic (PVL-b-MePEG)(6) copolymers increase with an increase in the PVL molecular weight. Micelles were prepared from the (PVL-b-MePEG)(6) copolymers via the dialysis method and found to have effective mean diameters ranging from 10 to 45 nm, depending on the copolymer composition. In addition, the (PVL-b-MePEG)(6) copolymers having lower PVL content were found to form micelles with a narrow monomodal size distribution, whereas the copolymers having higher PVL content tended to form aggregates with a bimodal size distribution. The noncytotoxicity of the copolymers was also confirmed in CHO-K1 fibroblast cells using a cell viability assay, indicating that the (PVL-b-MePEG)(6) copolymers are suitable for biomedical applications such as drug delivery. PMID:16004456

Zeng, Faquan; Lee, Helen; Chidiac, Marc; Allen, Christine

2005-01-01

391

Total syntheses of bengamides B and E.  

Science.gov (United States)

Total syntheses of the cytotoxic marine natural products bengamides B and E are described. Both bengamides are prepared via amide coupling of a protected polyhydroxylated lactone intermediate 9 with a suitably substituted aminocaprolactam intermediate. Lactone 9 is prepared in five steps from commercially available alpha-D-glucoheptonic gamma-lactone. The key reactions are a selective deprotection of a 1,2-acetonide in the presence of a 1,3-acetonide and an (E)-selective olefination of an unstable aldehyde using a gem-dichromium reagent. The bengamide B lactam intermediate 10 is prepared in seven steps from commercially available (5R)-5-hydroxy-L-lysine (12). The desired S-configuration at the gamma-OH lactam position is established using the Mitsunobu reaction. PMID:11300909

Kinder, F R; Wattanasin, S; Versace, R W; Bair, K W; Bontempo, J; Green, M A; Lu, Y J; Marepalli, H R; Phillips, P E; Roche, D; Tran, L D; Wang, R; Waykole, L; Xu, D D; Zabludoff, S

2001-03-23

392

Properties of flame synthesized germanium oxide nanoparticles.  

Science.gov (United States)

Germanium oxide (GeOx) nanoparticles in the size range from 1.5 to 10 nm were synthesized in a low-pressure premixed H2/O2/Ar flame in the pressure range 25-55 mbar. The flame was doped with different amounts of tetramethylgermanium (Ge(CH3)4) ranging from 500 to 2000 ppm. The influence of process parameters such as pressure, flame coordinate, and cold gas flow velocity with respect to growth of germanium oxide particles were investigated. The formed particles were analyzed in-situ according to their mass and charge by means of a particle mass spectrometer (PMS). The specific surface area was determined ex-situ by the BET method. The crystal structure and chemical composition of the produced nanopowder was characterized by EDX and XRD measurements. Additionally, the particles were analyzed by means of FT-IR spectroscopy. PMID:15913252

Simanzhenkov, Vasily; Wiggers, Hartmut; Roth, Paul

2005-03-01

393

PZT Powders Synthesized by Hydrothermal Method  

Directory of Open Access Journals (Sweden)

Full Text Available Lead zirconate titanate (PZT) powders with single―phase, cubic morphology and average size of 1 ?m were synthesized using hydrothermal methods. Effects of KOH concentration, hydrothermal treatment time and Pb excess were investigated. The results show that KOH concentration has an important influence on the solid solubility of Pb ion in A―site of PZT perovskite structure. The concentration of Pb2+ vacancies increased with the increase of OH― concentration. However, this kind of deficiency could be compensated by adding more Pb ions in the raw materials, and more Pb ions were needed to add with higher alkaline concentration in the starting solution. But excessive compensation of Pb ions would result in the appearance of the second phase.

ZHU Kong-Jun, ZHU Ren-Qiang, DONG Na-Na, GU Hong-Hui, QIU Jin-Hao, JI Hong-Li

2012-05-01

394

Structure of the enzymatically synthesized fructan inulin  

International Nuclear Information System (INIS)

Construction, purification and characterization of a fusion protein of maltose-binding protein of Escherichia coli and the fructosyltransferase of Streptococcus mutans is described. With the purified protein, in vitro synthesis of inulin was performed. The obtained polysaccharide was characterized by high-performance size-exclusion chromatography (HPSEC) and static light scattering (SLS) in dilute aqueous and dimethyl sulfoxide solution. For all samples very high molecular weights between 60x106 and 90x106 g/mol and a remarkable small polydispersity index of 1.1 have been determined. Small root-mean-square radii of gyration point to a compact conformation in dilute solution. No difference between native and enzymatically synthesized inulin was observed by X-ray powder diffraction and thermoanalysis of solid samples. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

1998-12-15

395

Syntheses and degradations of fluorinated heterocyclics  

Science.gov (United States)

The relative stability of two ring systems, the triazine rings and 1,2,4-oxadiazoles, which offer potential crosslinks useful for curing perfluoroalkyl ether elastomers, has been investigated. Tris (perfluoro-n-heptyl)-s-triazine, the perfluoroether substituted-s-triazine, 1,4-bis/(5-perfluoro-n-heptyl)-1,2,4-oxadiazolyl/benzene, its perfluoroalkyl ether substituted analog, and 3,5-bis-(perfluoro-n-heptyl)-1,2,4-oxadiazole were synthesized and subjected to thermal and oxidative degradation at 235 and 325 C and to hydrolytic degradation at 235 C. The perfluoroalkyl ether substituted triazine and 3,5-bis(perfluoro-n-heptyl)-1,2,4-oxadiazole were found to be stable under all conditions investigated.

Paciorek, K. L.; Kratzer, R. H.; Kaufman, J.; Rosser, R. W.

1975-01-01

396

Arm swing in human walking: What is their drive?  

Science.gov (United States)

Although previous research has studied arm swing during walking, to date, it remains unclear what the contribution of passive dynamics versus active muscle control to arm swing is. In this study, we measured arm swing kinematics with 3D-motion analysis. We used a musculoskeletal model in OpenSim and generated dynamic simulations of walking with and without upper limb muscle excitations. We then compared arm swing amplitude and relative phase during both simulations to verify the extent to which passive dynamics contribute to arm swing. The results confirm that passive dynamics are partly responsible for arm swing during walking. However, without muscle activity, passive swing amplitude and relative phase decrease significantly (both p<0.05), the latter inducing a more in-phase swing pattern of the arms. Therefore, we conclude that muscle activity is needed to increase arm swing amplitude and modify relative phase during human walking to obtain an out-phase movement relative to the legs. PMID:24865637

Goudriaan, Marije; Jonkers, Ilse; van Dieen, Jaap H; Bruijn, Sjoerd M

2014-06-01

397

76 FR 76954 - 36(b)(1) Arms Sales Notification  

Science.gov (United States)

...text of a section 36(b)(1) arms sales notification...INFORMATION CONTACT: Ms. B. English, DSCA/DBO...Pursuant to Section 36(b)(1) of the Arms Export...ii) Total Estimated Value: Major Defense Equipment...DSU-40 Laser Sensors, 3000 GBU-38(V)1 JDAM...

2011-12-09

398

AGRICULTURAL RUNOFF MANAGEMENT (ARM) MODEL VERSION II: REFINEMENT AND TESTING  

Science.gov (United States)

The Agricultural Runoff Management (ARM) Model has been refined and tested on small agricultural watersheds in Georgia and Michigan. The ARM Model simulates the hydrologic, sediment production, pesticide, and nutrient processes on the land surface and in the soil profile that det...

399

Stellar dynamics around transient co-rotating spiral arms  

Directory of Open Access Journals (Sweden)

Full Text Available 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 an N-body/SPH simulation of a Milky Way-sized barred disk, 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 tat all radii where there is a co-rotating spiral arm the particles continue to be accelerated (decelerated by the spiral arm for long periods, which leads to strong migration.

Cropper M.

2012-02-01

400

Stellar dynamics around transient co-rotating spiral arms  

CERN Multimedia

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 an N-body/SPH simulation of a Milky Way-sized barred disk, 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 at all radii where there is a co-rotating spiral arm the particles continue to be accelerated (decelerated) by the spiral arm for long periods, which lead...

Kawata, Daisuke; Cropper, Mark

2011-01-01

 
 
 
 
401

ARM tõestab, et ka analüütikud eksivad / Fredy-Edwin  

Index Scriptorium Estoniae

Apple'i iPadidele ja iPhone'idele kiipe tootva Suurbritannia firma ARM Holdings aktsia on kõige suurem tõusja Londoni FTSE 100 indeksi kuue kuu, 12 kuu, 18 kuu, kahe aasta ja kolme aasta lõikes, samas on analüütikud kõigist indeksi aktsiatest kõige negatiivsemalt meelestatud just ARM Holdingsi suhtes. Graafik

Esse, Fredy-Edwin

2011-01-01

402

Arms Control and National Security: An Introduction. Advance Edition.  

Science.gov (United States)

Suitable for use with high school students, this booklet on arms control and national security provides background information, describes basic concepts, reviews recent history, and offers suggestions for further reading. The first section, on American attitudes toward national security and arms control, defines five types of limits on weapons…

Arms Control Association, Washington, DC.

403

Conventional Arms Control and Europe's Future. Headline Series No. 287.  

Science.gov (United States)

This brief issues booklet provides basic information about the arms control issue in Europe, as of 1988. The table of contents includes the following: (1) "Trying Again"; (2) "Prelude to Arms Control"; (3) "The First Attempts: MBFR (Mutual and Balanced Force Reductions) and CSCE (Conference on Security and Cooperation in Europe); (4) "CAFE…

Sloan, Stanley R.

404

Modelling and control of two coordinated robot arms  

Science.gov (United States)

Two coordinated robot arms are modeled by considering the two arms as working on the same object simultaneously and as a closed kinematic chain. In both formulations, a novel dynamic control method is used which is based on feedback linearization and simultaneous output decoupling.

Tarn, T. J.; Yun, X.; Bejczy, A. K.

1988-01-01

405

Attitudes about Arms Control and Effects of "The Day After."  

Science.gov (United States)

An 18-item questionnaire was designed to investigate relationships between attitude towards arms control and beliefs about nuclear weapon effects, probability of war, Soviet goals, and the importance of nuclear arms superiority. Effects of the television movie, "The Day After," were also assessed by administering the questionnaire eight days…

Nelson, Linden L.; Slem, Charles M.

406

Contractures and Hypertonia of the Arm After Stroke  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Veel patiënten die een beroerte (cerebrovasculair accident, CVA) hebben doorgemaakt verliezen de mogelijkheid om de verlamde arm in te schakelen voor functionele activiteiten. Door het gebrek aan motorisch functieherstel blijft de arm geïmmobiliseerd waardoor zich CVA-specifieke herstelbelemmerende functiestoornissen ontwikkelen zoals hypertonie, spierverkortingen (contracturen) en schouderpijn.

2014-01-01

407

Syntheses and Structure Determinations of Calcium Thiolates.  

Science.gov (United States)

The exploration of synthetic methodologies toward heavy alkaline-earth chalcogenolates resulted in the preparation and structural characterization of a family of calcium thiolates, including [Ca(SC(6)F(5))(2)(py)(4)], 1 (py = pyridine), the separated ion-triple [Ca(18-crown-6)(NH(3))(3))][SMes](2).2THF, 2 (Mes = 2,4,6-tBu(3)C(6)H(2)), and the contact triple [Ca(18-crown-6)(SMes)(2)].THF, 3. Compound 1 was prepared by treating [Ca(N(SiMe(3))(2))(2)](2) with 4 equiv of HSC(6)F(5) under addition of pyridine. The thiolates 2 and 3 were synthesized by treatment of calcium metal dissolved in dry, liquid NH(3) under addition of 2 equiv of HSMes and crown ether or, alternatively, by the reduction of MesSSMes with calcium metal in dry, liquid ammonia. We also report two reaction products isolated during attempted calcium thiolate syntheses: [CaBr(4)(THF)(2)(&mgr;(2)-Li)(2)(THF)(4)], 4, isolated as the product of a salt elimination reaction between CaBr(2) and 2 equiv of [Li(THF)(n)()S-2,4,6-(i)()Pr(3)C(6)H(2)](m)(). [(NH(4))(py)(SC(6)F(5))], 5, was obtained as the sole product in the reaction of metallic calcium with HSC(6)F(5) in liquid ammonia under addition of pyridine. All compounds were characterized by single-crystal X-ray crystallography in addition to IR and NMR spectroscopy. PMID:11670626

Chadwick, Scott; Englich, Ulrich; Noll, Bruce; Ruhlandt-Senge, Karin

1998-09-01

408

National Gas Survey. Synthesized gaseous hydrocarbon fuels  

Energy Technology Data Exchange (ETDEWEB)

The supply-Technical Advisory Task Force-Synthesized Gaseous Hydrocarbon Fuels considered coal, hydrocarbon liquids, oil shales, tar sands, and bioconvertible materials as potential feedstocks for gaseous fuels. Current status of process technology for each feedstock was reviewed, economic evaluations including sensitivity analysis were made, and constraints for establishment of a synthesized gaseous hydrocarbon fuels industry considered. Process technology is presently available to manufacture gaseous hydrocarbon fuels from each of the feedstocks. In 1975 there were eleven liquid feedstock SNG plants in the United States having a capacity of 1.1 billion SCFD. There can be no contribution of SNG before 1982 from plants using feedstocks other than liquids because there are no plants in operation or under construction as of 1977. Costs for SNG are higher than current regulated prices for U.S. natural gas. Because of large reserves, coal is a prime feedstock candidate although there are major constraints in the area of coal leases, mining and water permits, and others. Commercial technology is available and several new gasification processes are under development. Oil shale is also a feedstock in large supply and commercial process technology is available. There are siting and permit constraints, and water availability may limit the ultimate size of an oil shale processing industry. Under projected conditions, bioconvertible materials are not expected to support the production of large quantities of pipeline quality gas during the next decade. Production of low or medium Btu gas from municipal solid wastes can be expected to be developed in urban areas in conjunction with savings in disposal costs. In the economic evaluations presented, the most significant factor for liquid feedstock plants is the anticipated cost of feedstock and fuel. The economic viability of plants using other feedstocks is primarily dependent upon capital requirements.

None

1978-06-01

409

ARM Surface Meteorology Systems Instrument Handbook  

Energy Technology Data Exchange (ETDEWEB)

The ARM Surface Meteorology Systems consist mainly of conventional in situ sensors that obtain a defined “core” set of measurements. The core set of measurements is: Barometric Pressure (kPa), Temperature (°C), Relative Humidity (%), Arithmetic-Averaged Wind Speed (m/s), Vector-Averaged Wind Speed (m/s), and Vector-Averaged Wind Direction (deg). The sensors that collect the core variables are mounted at the standard heights defined for each variable: • Winds: 10 meters • Temperature and Relative Humidity: 2 meters • Barometric Pressure: 1 meter. Depending upon the geographical location, different models and types of sensors may be used to measure the core variables due to the conditions experienced at those locations. Most sites have additional sensors that measure other variables that are unique to that site or are well suited for the climate of the location but not at others.

Ritsche, MT

2011-03-08

410

Martian Dust Collected by Phoenix's Arm  

Science.gov (United States)

This image from NASA's Phoenix Lander's Optical Microscope shows particles of Martian dust lying on the microscope's silicon substrate. The Robotic Arm sprinkled a sample of the soil from the Snow White trench onto the microscope on July 2, 2008, the 38th Martian day, or sol, of the mission after landing. Subsequently, the Atomic Force Microscope, or AFM, zoomed in one of the fine particles, creating the first-ever image of a particle of Mars' ubiquitous fine dust, the most highly magnified image ever seen from another world. The Atomic Force Microscope was developed by a Swiss-led consortium in collaboration with Imperial College London. The AFM is part of Phoenix's Microscopy, Electrochemistry and Conductivity Analyzer instrument. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

2008-01-01

411

Phoenix Robotic Arm's Workspace After 90 Sols  

Science.gov (United States)

During the first 90 Martian days, or sols, after its May 25, 2008, landing on an arctic plain of Mars, NASA's Phoenix Mars Lander dug several trenches in the workspace reachable with the lander's robotic arm. The lander's Surface Stereo Imager camera recorded this view of the workspace on Sol 90, early afternoon local Mars time (overnight Aug. 25 to Aug. 26, 2008). The shadow of the the camera itself, atop its mast, is just left of the center of the image and roughly a third of a meter (one foot) wide. The workspace is on the north side of the lander. The trench just to the right of center is called 'Neverland.' The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

2008-01-01

412

Cloud and Star Formation in Spiral Arms  

CERN Document Server

We present the results from simulations of GMC formation in spiral galaxies. First we discuss cloud formation by cloud-cloud collisions, and gravitational instabilities, arguing that the former is prevalent at lower galactic surface densities and the latter at higher. Cloud masses are also limited by stellar feedback, which can be effective before clouds reach their maximum mass. We show other properties of clouds in simulations with different levels of feedback. With a moderate level of feedback, properties such as cloud rotations and virial parameters agree with observations. Without feedback, an unrealistic population of overly bound clouds develops. Spiral arms are not found to trigger star formation, they merely gather gas into more massive GMCs. We discuss in more detail interactions of clouds in the ISM, and argue that these are more complex than early ideas of cloud-cloud collisions. Finally we show ongoing work to determine whether the Milky Way is a flocculent or grand design spiral.

Dobbs, Clare

2014-01-01

413

Wireless Control & Monitoring of Robotic Arm (SWORDS  

Directory of Open Access Journals (Sweden)

Full Text Available Robot warriors have already seen action in Iraq, and the US Army plans to replace one-third of its armored vehicles and weapons with robots by 2015. These killing machines may one day come equipped with an artificial conscience even to the extent of disobeying immoral orders. The US Army's latest recruits are 1 meter (about 3 feet tall, wear desert camouflage and are armed with black M249 machine guns. They also move on caterpillar tracks and thanks to five camera eyes can even see in the dark. The fearless fighters are three robot soldiers who, unnoticed by the general public, were deployed in Iraq in mid-June, charged with hunting down insurgents. As if guided by an unseen hand, they hone in on their targets and fire at them with their machine guns.

R.A. Kadu,

2012-02-01

414

Computer aided control of a mechanical arm  

Science.gov (United States)

A method for computer-aided remote control of a six-degree-of-freedom manipulator arm involved in the on-orbit servicing of a spacecraft is presented. The control configuration features a supervisory type of control in which each of the segments of a module exchange trajectory is controlled automatically under human supervision, with manual commands to proceed to the next step and in the event of a failure or undesirable outcome. The implementation of the supervisory system is discussed in terms of necessary onboard and ground- or Orbiter-based hardware and software, and a one-g demonstration system built to allow further investigation of system operation is described. Possible applications of the system include the construction of satellite solar power systems, environmental testing and the control of heliostat solar power stations.

Derocher, W. L., Jr.; Zermuehlen, r. O.

1979-01-01

415

Control framework for hand-arm coordination  

Science.gov (United States)

Coordination of multiple manipulators requires cooperation at several levels in the control hierarchy. A distributed processing environment with no hardware dependencies except at the motor servo level would provide a flexible architecture for coordination. A system on these lines is being built to control an articulated hand and an arm. The four levels of control envisaged include a task decomposition level, a planning level, a scheduling level, and a server level. The hand will carry both force and tactile sensors, feedback from these are used to provide adaptive control in grasping tasks. The processing of the sensory information is performed by independent processes, with analyzed information being sent to the relevant layer of the system. The manipulators are also controlled by individual processes. All process can open communications with an active process sending commands or data, or receiving them. The scope of the system and the current setup are described along with future lines of development.

Agrawal, Sanjay

1990-01-01

416

Synthesis and evaluation of bipendant-armed (oligo)thiophene crown ether derivatives as new chemical sensors  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Three new (oligo)thiophene bipendant-armed ligands 2a-c, derived from 2-(aminomethyl)-15-crown-5, have been synthesized and characterized. Compounds 2a-c were prepared by reductive amination of the corresponding macrocycle with formyl thiophene derivatives 1a-c in the presence of NaBH(OAc)3 in fair to good yields. The photophysical properties of ligands 2a-c were studied and they were also evaluated as chemosensors in the presence of Na(I), Ag(I), Pd(II) and Hg(II) cations in acetonitrile sol...

2008-01-01

417

Two-Arm Flexible Thermal Strap  

Science.gov (United States)

Airborne and space infrared cameras require highly flexible direct cooling of mechanically-sensitive focal planes. A thermal electric cooler is often used together with a thermal strap as a means to transport the thermal energy removed from the infrared detector. While effective, traditional thermal straps are only truly flexible in one direction. In this scenario, a cooling solution must be highly conductive, lightweight, able to operate within a vacuum, and highly flexible in all axes to accommodate adjustment of the focal plane while transmitting minimal force. A two-armed thermal strap using three end pieces and a twisted section offers enhanced elastic movement, significantly beyond the motion permitted by existing thermal straps. This design innovation allows for large elastic displacements in two planes and moderate elasticity in the third plane. By contrast, a more conventional strap of the same conductance offers less flexibility and asymmetrical elasticity. The two-arm configuration reduces the bending moment of inertia for a given conductance by creating the same cross-sectional area for thermal conduction, but with only half the thickness. This reduction in the thickness has a significant effect on the flexibility since there is a cubic relationship between the thickness and the rigidity or bending moment of inertia. The novelty of the technology lies in the mechanical design and manufacturing of the thermal strap. The enhanced flexibility will facilitate cooling of mechanically sensitive components (example: optical focal planes). This development is a significant contribution to the thermal cooling of optics. It is known to be especially important in the thermal control of optical focal planes due to their highly sensitive alignment requirements and mechanical sensitivity; however, many other applications exist including the cooling of gimbal-mounted components.

Urquiza, Eugenio; Vasquez, Cristal; Rodriquez, Jose I.; Leland, Robert S.; VanGorp, Byron E.

2011-01-01

418

A dual-armed free flyer  

Science.gov (United States)

This summary presents the main conclusions and results of the design studies conducted by a group of 13 students at the University of Maryland. The students, all participants in the spring 1989 course ENEE418 in the Electrical Engineering Department, met weekly in a two-hour class to discuss and evaluate design alternatives. The main problem considered was the design and control of a planar testbed simulating a free-flying space robot for applications in satellite servicing. This project grew out of the 1988 class where a dual-armed free flyer (DAFF) was designed and partially built. This year, a group of six students continued the development of the DAFF, achieving computer-controlled motion of the DAFF's arms. All fabrication and testing of the DAFF is being conducted in the Intelligent Servosystems Laboratory at the University of Maryland. While the work related to the design and development of the DAFF is the main subject of the report, it should be noted that other students in the ENEE418 class have investigated additional issues related to manipulation in space. For example, one group studied a new parallel linkage based manipulator for fine motion applications such as in assembly operations in space. They investigated the mechanism's kinematics, its reachable workspace, and precision of applying forces and torques. In yet another project, a student set out to measure and map the friction characteristics of the actuators used in the Modular Dextrous Hand, which has been recently developed in the Intelligent Servosystems Laboratory. The results are expected to help compensate for this friction, which is a highly nonlinear disturbance and presents significant problems in high-precision, low-speed operations. This summary continues with the discussion of the results obtained by the group of students who have been working on developing the DAFF testbed.

Beck, D.; Das, B.; Dickson, C.; Douglas, B.; Long, L.; Middour, K.; Reid, S.; Uber, J.; Walsh, G.; Wang, L.

1989-01-01

419

Object Sorting System Using Robotic Arm  

Directory of Open Access Journals (Sweden)

Full Text Available The paper presents a smart approach for a real time inspection and selection of objects in continuous flow. Image processing in today’s world grabs massive attentions as it leads to possibilities of broaden application in many fields of high technology. The real challenge is how to improve existing sorting system in the modular processing system which consists of four integrated stations of identification, processing, selection and sorting with a new image processing feature. Existing sorting method uses a set of inductive, capacitive and optical sensors do differentiate object color. This paper presents a mechatronics color sorting system solution with the application of image processing. Image processing procedure senses the objects in an image captured in real-time by a webcam and then identifies color and information out of it. This information is processed by image processing for pick-and-place mechanism. The sorting process is based on a 2 phase operative methodology defined 1 a self-learning step where the apparatus learns to identify objects ; 2 an operative selection process where objects are detected, classified using a decisional algorithm and selected in real time. The Project deals with an automated material handling system. It aims in classifying the colored objects by colour, size, which are coming on the conveyor by picking and placing the objects in its respective pre-programmed place. Thereby eliminating the monotonous work done by human, achieving accuracy and speed in the work. The project involve sensors that senses the object’s colour, size and sends the signal to the microcontroller. The microcontroller sends signal to circuit which drives the various motors of the robotic arm to grip the object and place it in the specified location. Based upon the detection, the robotic arm moves to the specified location, releases the object and comes back to the original position [1] [2].

VISHNU R.KALE, V.A.KULKARNI

2013-07-01

420

Testbed model and data assimilation for ARM  

International Nuclear Information System (INIS)

The objectives of this contract are to further develop and test the ALFA (AER Local Forecast and Assimilation) model originally designed at AER for local weather prediction and apply it to three distinct but related purposes in connection with the Atmospheric Radiation Measurement (ARM) program: (a) to provide a testbed that simulates a global climate model in order to facilitate the development and testing of new cloud parametrizations and radiation models; (b) to assimilate the ARM data continuously at the scale of a climate model, using the adjoint method, thus providing the initial conditions and verification data for testing parameumtions; (c) to study the sensitivity of a radiation scheme to cloud parameters, again using the adjoint method, thus demonstrating the usefulness of the testbed model. The data assimilation will use a variational technique that minimizes the difference between the model results and the observation during the analysis period. The adjoint model is used to compute the gradient of a measure of the model errors with respect to nudging terms that are added to the equations to force the model output closer to the data. The radiation scheme that will be included in the basic ALFA model makes use of a gen two-stream approximation, and is designed for vertically inhonogeneous, multiple-scattering atmospheres. The sensitivity of this model to the definition of cloud parameters will be studied. The adjoint technique will also be used to compute the sensitivities. This project is designed to provide the Science Team members with the appropriate tools and modeling environment for proper testing and tuning of new radiation models and cloud parametrization schemes

1992-01-01

 
 
 
 
421

Sprinkle Test by Phoenix's Robotic Arm (Movie)  

Science.gov (United States)

NASA's Phoenix Mars Lander used its Robotic Arm during the mission's 15th Martian day since landing (June 9, 2008) to test a 'sprinkle' method for delivering small samples of soil to instruments on the lander deck. This sequence of four images from the spacecraft's Surface Stereo Imager covers a period of 20 minutes from beginning to end of the activity. In the single delivery of a soil sample to a Phoenix instrument prior to this test, the arm brought the scooped up soil over the instrument's opened door and turned over the scoop to release the soil. The sprinkle technique, by contrast, holds the scoop at a steady angle and vibrates the scoop by running the motorized rasp located beneath the scoop. This gently jostles some material out of the scoop to the target below. For this test, the target was near the upper end the cover of the Microscopy, Electrochemistry and Conductivity Analyzer instrument suite, or MECA. The cover is 20 centimeters (7.9 inches) across. The scoop is about 8.5 centimeters (3.3 inches) across. Based on the test's success in delivering a small quantity and fine-size particles, the Phoenix team plans to use the sprinkle method for delivering samples to MECA and to the Thermal and Evolved-Gas Analyzer, or TEGA. The next planned delivery is to MECA's Optical Microscope, via the port in the MECA cover visible at the bottom of these images. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

2008-01-01

422

The Arms Trade Treaty (ATT): a public health imperative.  

Science.gov (United States)

The United Nations adopted an historic international Arms Trade Treaty (ATT) in April 2013. A 1997 meeting of Nobel Peace Prize laureates who called for an International Code of Conduct to address the 'destructive effects of the unregulated arms trade' initiated discussions that led to the Treaty. Public health institutions, including the World Health Organization and the International Committee of the Red Cross, and nongovernmental health groups such as International Physicians for the Prevention of Nuclear War, made adoption of the ATT a public health imperative. The poorly regulated $70 billion annual trade in conventional arms fuels conflict, with devastating effects on global health. The ATT aims to 'reduce human suffering'. It prohibits arms' sales if there is knowledge that the arms would be used in the commission of genocide, attacks against civilians, or war crimes. The health community has much to contribute to ensuring ratification and implementation of the ATT. PMID:24257633

Valenti, Maria; Mtonga, Robert; Gould, Robert; Christ, Michael

2014-02-01

423

Guest Editorial: Research update: VA study to optimize DEKA Arm  

Directory of Open Access Journals (Sweden)

Full Text Available In 2005, the Defense Advanced Research Projects Agency (DARPA announced its Revolutionizing Prosthetics program and funded the development of the DEKA prosthetic arm. The DEKA Arm System incorporates major technological advances such as flexible socket design, innovative control features, software, and hardware that together enable enhanced functionality that promises to surpass any currently available prosthetic device. In 2008, the Department of Veterans Affairs (VA entered into an agreement with DARPA to conduct clinical evaluations of the prototype DEKA Arm System, a prosthetic device system still under development and not yet available commercially. Studies of the DEKA Arm System have been underway at VA sites since late 2008, with the first subject fitted with a DEKA Arm in early 2009.

Linda Resnik, PT, PhD

2010-05-01

424

Exoskeleton to Rehabilitate Paralyzed Arm Based on Patient Healthy Arm Guidance  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper we discuss the stroke rehabilitation by robotic device and a novel exoskeleton, which is based on the patient's self-guided control will be presented. It is realized by moving the patient’s own healthy arm in order to provide the movement trajectories for the exoskeleton. The main advantage of the exoskeleton is its flexibility and adaptivity for individual patient’s rehabilitation training. A new model predictive control (MPC algorithm for handling coupling and nonlinearity is also proposed and a microprocessor-based drive system for the exoskeleton will be adopted. In addition, to measure the angular positions corresponding to the joint angles of arm high resolution potentiometers are used.

Jiajia Hu

2013-05-01

425

Poly(glycolide) multi-arm star polymers: Improved solubility via limited arm length  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Due to the low solubility of poly(glycolic acid) (PGA), its use is generally limited to the synthesis of random copolyesters with other hydroxy acids, such as lactic acid, or to applications that permit direct processing from the polymer melt. Insolubility is generally observed for PGA when the degree of polymerization exceeds 20. Here we present a strategy that allows the preparation of PGA-based multi-arm structures which significantly exceed the molecular weight of processable oligomeric l...

Wolf, Florian K.; Fischer, Anna M.; Frey, Holger

2010-01-01

426

Exoskeleton to Rehabilitate Paralyzed Arm Based on Patient Healthy Arm Guidance  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper we discuss the stroke rehabilitation by robotic device and a novel exoskeleton, which is based on the patient's self-guided control will be presented. It is realized by moving the patient’s own healthy arm in order to provide the movement trajectories for the exoskeleton. The main advantage of the exoskeleton is its flexibility and adaptivity for individual patient’s rehabilitation training. A new model predictive control (MPC) algorithm for handling coupling and nonlinearit...

2013-01-01

427

33 CFR 167.1703 - In Prince William Sound: Valdez Arm Traffic Separation Scheme.  

Science.gov (United States)

...2009-07-01 false In Prince William Sound: Valdez Arm Traffic Separation Scheme. 167.1703... § 167.1703 In Prince William Sound: Valdez Arm Traffic Separation Scheme. The Valdez Arm Traffic Separation Scheme consists of...

2009-07-01

428

77 FR 52105 - Announcement of the Innovation in Arms Control Challenge Under the America Competes...  

Science.gov (United States)

...Announcement of the Innovation in Arms Control Challenge Under the America Competes...Department of State's Bureau of Arms Control, Verification and Compliance...challenge: How Can the Crowd Support Arms Control Transparency Efforts? This...

2012-08-28

429

78 FR 52680 - Amendment to the International Traffic in Arms Regulations: Registration and Licensing of Brokers...  

Science.gov (United States)

...the brokering amendment to the Arms Export Control Act (AECA) (section 38(b...the Under Secretary of State for Arms Control and International Security or...the Under Secretary of State for Arms Control and International Security...

2013-08-26

430

78 FR 43959 - Announcement of the 2013 Innovation in Arms Control Challenge Under the America Competes...  

Science.gov (United States)

...Announcement of the 2013 Innovation in Arms Control Challenge Under the America Competes...Department of State's Bureau of Arms Control, Verification and Compliance...and Concepts Can Support Future Arms Control Inspections? The 2013...

2013-07-22

431

76 FR 818 - Bureau of Nonproliferation; Determination Under the Arms Export Control Act  

Science.gov (United States)

...Nonproliferation; Determination Under the Arms Export Control Act AGENCY: Department of State...Under Secretary of State for Arms Control and International Security has...pursuant to Section 73 of the Arms Export Control Act and has concluded that...

2011-01-06

432

78 FR 47179 - Amendment to the International Traffic in Arms Regulations: Libya and UNSCR 2095  

Science.gov (United States)

...Office of Defense Trade Controls Policy, U.S. Department...which further modified the arms embargo against Libya...Other sales or supply of arms and related materiel...Acting Under Secretary, Arms Control and International...

2013-08-05

433

Kootenay Lake Fertilization Experiment, Year 15 (North Arm) and Year 3 (South Arm) (2006) Report  

Energy Technology Data Exchange (ETDEWEB)

This report summarizes results from the fifteenth year (2006) of nutrient additions to the North Arm of Kootenay Lake and three years of nutrient additions to the South Arm. Experimental fertilization of the lake has been conducted using an adaptive management approach in an effort to restore lake productivity lost as a result of nutrient uptake in upstream reservoirs. The primary objective of the experiment is to restore kokanee (Oncorhynchus nerka) populations, which are the main food source for Gerrard rainbow trout (Oncorhynchus mykiss) and bull trout (Salvelinus confluentus). The quantity of agricultural grade liquid fertilizer (10-34-0, ammonium polyphosphate and 28-0-0, urea ammonium nitrate) added to the North Arm in 2006 was 44.7 tonnes of P and 248.4 tonnes of N. The total fertilizer load added to the South Arm was 257 tonnes of nitrogen; no P was added. Kootenay Lake has an area of 395 km{sup 2}, a maximum depth of 150 m, a mean depth of 94 m, and a water renewal time of approximately two years. Kootenay Lake is a monomictic lake, generally mixing from late fall to early spring and stratifying during the summer. Surface water temperatures generally exceed 20 C for only a few weeks in July. Results of oxygen profiles were similar to previous years with the lake being well oxygenated from the surface to the bottom depths at all stations. Similar to past years, Secchi disc measurements at all stations in 2006 indicate a typical seasonal pattern of decreasing depths associated with the spring phytoplankton bloom, followed by increasing depths as the bloom gradually decreases by the late summer and fall. Total phosphorus (TP) ranged from 2-7 {micro}g/L and tended to decrease as summer advanced. Over the sampling season dissolved inorganic nitrogen (DIN) concentrations decreased, with the decline corresponding to nitrate (the dominant component of DIN) being utilized by phytoplankton during summer stratification. Owing to the importance of epilimnetic nitrate that is required for optimal phytoplankton growth discrete depth water sampling occurred in 2006 to measure more accurately changes in the nitrate concentrations. As expected there was a seasonal decline in nitrate concentrations, thus supporting the strategy of increasing the nitrogen loading in both arms. These in-season changes emphasize the need for an adaptive management approach to ensure the nitrogen to phosphorus (N:P) rat