WorldWideScience
1

Preparation of hexaaza and heptaaza macrocycles functionalized with a single aminoalkyl pendant arm.  

Science.gov (United States)

A practical and reproducible route for the preparation of 1,4,7,10,13,16,19-heptaazacyclohenicosane (1), 1,4,7,10,13,16-hexaazacyclooctadecane (2), and 1,4,7,10,13,17-hexaazacycloicosane (3) bearing a single N-(2-aminoethyl) pendant arm has been developed. Richman-Atkins cyclization in the presence of caesium carbonate was applied to construct the macrocycle from 3-benzoyl-N1,N5-ditosyl-3-azapentane-1.5-diamine and the appropriate fully N-tosylated N alpha, N omega-bis(2-mesyloxyethyl) tri- or tetra-amine. The benzoyl group was selectively removed with potassium tert-butoxide, and the exposed nitrogen atom was reacted with N-tosylaziridine. The tosyl protections were removed with hydrogen bromide in acetic acid, and the product was converted to a free base with the aid of a strong anion exchange resin (OH- form). PMID:12929370

Zhang, Zhibo; Mikkola, Satu; Lönnberg, Harri

2003-03-01

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

New main-group and early transition-metal complexes of mono-pendant arm triazacyclononane ligands  

OpenAIRE

A family of new Group 3, Group 13 and early transition metal complexes of the previously described monoanionic, pendant arm macrocyclic ligands L a, L b and L c are described where HL a = (3,5-dimethyl-2-hydroxybenzyl)-4,7-diisopropyl-1,4,7-triazacyclononane 1a, HL b = (3,5-di-tert-butyl-2-hydroxybenzyl)-4,7-diisopropyl-1,4,7-triazacyclonon ane 1b, and HL ...

Bylikin, Sy; Robson, Da; Male, Nah; Rees, Lh; Mountford, P.; Schroder, M.

2001-01-01

4

Construction of a peptide with an electroactive daunomycin like a pendant arm to detect ovalbumin.  

Science.gov (United States)

In this study, a peptide-1 (RNRCKGTDVQAW) constructing lysozyme was conjugated with an electroactive daunomycin in order to voltammetrically detect ovalbumin (OVA). Hetero-bifunctional cross-linking agents with four kinds of ethylene chains in differing lengths were used to bind the peptide-1 and daunomycin. After a cross-linking agent had reacted with an amino group of daunomycin, the compound was introduced into the peptide to the cysteine residue in the peptide using a pendant arm. The OVA was sensed via a change in the electrode response of the daunomycin moiety, based on the binding between the peptide and the OVA. The adsorption of the peptide probe on the electrode increased with increases in the ethylene chain. The binding constants between the peptide probes and the OVA, however, did not depend on the length of the chain. This was because the ethylene chain influenced the binding. When the peptide and the daunomycin were bound using N-(6-maleimidocaproyloxy) sulfosuccinimide, the electrode response of the peptide probe was the most sensitive from among the four cross-linking agents. The calibration curve of the OVA using the peptide probe was linear and ranged from 1.5×10(-11) to 3.0×10(-10)M. Furthermore, this method could be applied to the electrochemical sensing of the OVA in egg whites and in fetal bovine serum. PMID:25604822

Sugawara, Kazuharu; Kadoya, Toshihiko; Kuramitz, Hideki

2015-02-01

5

Oxo-anion recognition by mono- and bisurea pendant-arm macrocyclic complexes.  

Science.gov (United States)

The novel macrocyclic copper(II) complexes [2](2+) and [3](2+), carrying one or two (nitrophenyl)urea fragments appended to an azacyclam or diazacyclam framework, exploit the hydrogen-bond-forming abilities of the urea subunits, along with the metal-ligand interaction, in the recognition of anionic species. Equilibrium studies in acetonitrile performed on [2](2+) and [3](2+) show that (nitrophenyl)urea pendant arms strongly interact with anionic species such as carboxylates and phosphates, which display both coordinating tendencies toward copper(II) and good affinity toward urea subunits. Stability constants of the adducts are considerably higher than those determined for the interaction of the same anions with a "plain urea" reference compound, confirming the synergistic action of metallomacrocyclic and urea subunits. Complex [2](2+) forms 1:1 adducts with acetate, benzoate, hydrogendiphosphate, and dihydrogen phosphate, while complex [3](2+) interacts with the same anions according to both 1:1 and 1:2 stoichiometries, with the exception of hydrogendiphosphate, which forms only the 1:1 adduct with a distinctly high association constant (log K > 7). Spectrophotometric investigations suggest that oxoanionic species interact with the complexes according to a "bridged" mode, inducing the macrocyclic systems to adopt a scorpionate-like conformation, as confirmed by crystallographic studies on the [3](2+)/succinate adduct. PMID:25529826

Boiocchi, Massimo; Licchelli, Maurizio; Milani, Michele; Poggi, Antonio; Sacchi, Donatella

2015-01-01

6

Justifier l'arme nucléaire. Le cas français pendant les années 1990  

OpenAIRE

La possession d’armements nucléaires n’est pas un phénomène irréversible. Partant de cette idée, nous nous sommes interrogés non pas sur ce qui fait que la France a acquis des armements nucléaires mais sur la raison pour laquelle elle les conserve. En l’occurrence, notre attention s’est portée sur la période qui s’étend de 1990 à 2000 pendant laquelle un débat stratégique nucléaire relativement important se développe. Il est l’occasion pour les stratégistes de réa...

Dumoulin, Andre?; Wasinski, Christophe

2010-01-01

7

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 E1pc = -0.62 to -0.76 V and E2pc = -1.21 to -1.31, and nickel(II) complexes (1-3) exhibit two irreversible one electron oxidation processes around E1pa = 1.08 to 1.14 V and E2pa = 1.71 to 1.74 V. 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.

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

2014-08-01

8

The effect on the lanthanide luminescence of structurally simple Eu(III) cyclen complexes upon deprotonation of metal bound water molecules and amide based pendant arms  

OpenAIRE

A series of substituted 1,4,7,10-tetraazacylcododecane ligands 1–4, possessing sensitizing nitrobenzene or naphthalene antennae, as one of the amide pendant arms, and their complexes with europium(III) were synthesised. The protonation constants and the metal ion stability constants of two of these ligands were determined by potentiometric titration . The pKa of the water molecules coordinated to the complexed metal ion were determined by both luminescent and potentiometric measurements. Th...

Gunnlaugsson, Thorfinnur

2010-01-01

9

TETA analogue containing one methylenephosphonate pendant arm: Lanthanide complexes and biological evaluation of its 153Sm and 166Ho complexes.  

Science.gov (United States)

The thermodynamic stability constants of complexes of 1,4,8,11-tetraazacyclotetradecane-1,4,8-triacetic-11-methylphosphonic acid (H5te3a1p) with La3+, Sm3+, Gd3+, Ho3+ and Lu3+ metal ions were determined by potentiometric titrations at 298.2 K and with ionic strength 0.10 M in N(CH3)4NO3. The complexes are formed relatively fast and the stability constants exhibited are good although lower than those found for the related ligands H4teta and H8tetp. At physiological pH the completely deprotonated complex species predominate, unlike what happens with the other mentioned ligands. The 153Sm and 166Ho complexes, 153Sm/166Ho-te3a1p, were synthesised quantitatively at pH 9 and 70 °C, and have shown good in vitro stability in human serum and physiological solutions except phosphate buffer (pH 7.4). The in vivo behaviour indicated that both complexes have a similar biological pattern, showing a slow tissue clearance, slow rate of total radioactivity excretion and some in vivo instability, although with some differences in their extend. These results indicate that the replacement of one acetate pendant arm of H4teta by a methylphosphonate one does not provide promising chelators to stabilize radiolanthanides for in vivo application. PMID:20888085

Lima, Luís M P; Delgado, Rita; Marques, Fernanda; Gano, Lurdes; Santos, Isabel

2010-12-01

10

153Sm and 166Ho complexes with tetraaza macrocycles containing pyridine and methylcarboxylate or methylphosphonate pendant arms.  

Science.gov (United States)

A set of tetraaza macrocycles containing pyridine and methylcarboxylate (ac(3)py14) or methylphosphonate (MeP(2)py14 and P(3)py14) pendant arms were prepared and their stability constants with La(3+), Sm(3+), Gd(3+) and Ho(3+) determined by potentiometry at 25 degrees C and 0.10 M ionic strength in NMe(4)NO(3). The metal:ligand ratio for (153)Sm and (166)Ho and for ac(3)py14, MeP(2)py14 and P(3)py14, as well as the pH of the reaction mixtures, were optimized to achieve a chelation efficiency higher than 98%. These radiocomplexes are hydrophilic and have a significant plasmatic protein binding. In vitro stability was studied in physiological solutions and in human serum. All complexes are stable in saline and PBS, but 20% of radiochemical impurities were detected after 24 h of incubation in serum. Biodistribution studies in mice indicated a slow rate of clearance from blood and muscle, a high and rapid liver uptake and a very slow rate of total radioactivity excretion. Some bone uptake was observed for complexes with MeP(2)py14 and P(3)py14, which was enhanced with time and the number of methylphosphonate groups. This biological profile supports the in vitro instability found in serum and is consistent with the thermodynamic stability constants found for these complexes. PMID:15338314

Marques, Fernanda; Guerra, Krassimira P; Gano, Lurdes; Costa, Judite; Campello, M Paula; Lima, Luís M P; Delgado, Rita; Santos, Isabel

2004-10-01

11

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  

OpenAIRE

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

12

Influence of the Pendant Arm, Halide, and Solvent on High-Efficient-Tuning [1 + 1] and [2 + 2] Schiff-Base Macrocyclic Complexes via a Zinc-Ion Template.  

Science.gov (United States)

A series of pendant-armed Schiff-base macrocyclic complexes 1-7 have been prepared by the condensation between extended dialdehydes with pendant arms (H2hpdd/H2pdd) and 1,3-propanediamine in the presence of ZnX2 (X = Cl, Br, I), where 18-membered [1 + 1] mononuclear and 36-membered [2 + 2] half-fold trinuclear macrocyclic zinc(II) complexes are yielded. Three experimental variables, i.e., the pendant arm, halide, and solvent, are found to influence the organization of final macrocyclic complexes, in addition to the conventional metal-ion template effect promoting reversible formation and cleavage of Schiff-base imine bonds. It is noted that all of the reactions produce singular macrocyclic complexes in high yields if the experimental variables are fixed, and the selection of different pendant arms and halide counterions will generate different [1 + 1] mononuclear and [2 + 2] trinuclear macrocyclic zinc(II) complexes. More interestingly, [1 + 1] and [2 + 2] macrocyclic zinc(II) complexes 2 and 3 can be produced in methanol and ethanol, respectively, in the case of the reaction between ZnBr2, H2pdd, and 1,3-propanediamine. Further experiments reveal that red solid 2 and yellow-green solid 3 can be transformed to each other just by altering the type of solvent, and this tuning is complete and reversible. PMID:25535804

Zhang, Kun; Qian, Huifen; Zhang, Lei; Huang, Wei

2015-01-20

13

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. Inly 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

14

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

Science.gov (United States)

Two new cyclen derivatives, H(2)do2nph and H(2)cb-do2nph, containing two trans-2-methyl-4-nitrophenol pendant arms and the latter including also an ethylene cross-bridge, were prepared in good yields using the bisaminal synthetic route. The two ligands were studied comparatively regarding their metal complexation behaviour. The copper(II) and zinc(II) complexes of H(2)do2nph and H(2)cb-do2nph were studied in dimethylsulfoxide-water (9 : 1 v/v) solution by a range of spectroscopic techniques. Copper(II) complexes were also studied in solid state by X-ray single crystal diffraction. These studies showed that the copper(II) and zinc(II) complexes of H(2)do2nph exhibited a distorted square pyramidal coordination environment with the four nitrogen atoms of the cyclen ring defining the basal plane, and that one of the nitrophenolate arms did not coordinate to the metal, independently of its protonation state. On the other hand, depending on the protonation state of one of the nitrophenolic arms, the cross-bridged derivative forms copper(II) complexes with distorted square pyramidal or octahedral geometries with one or two arms coordinated to the metal centre, respectively. In the complex with distorted octahedral geometry, the two phenolic oxygen atoms are coordinated to the metal centre in a cis-fashion. Acid-assisted dissociation assays in 1 mol dm(-3) HCl DMSO-H(2)O (9 : 1 v/v) solution at 298.2 K allowed one to determine the half-life of both copper(II) complexes, which is lower for the derivative without a cross-bridge as expected, while for the other one it is quite high and in line with similar cross-bridged cyclen derivatives from the literature. PMID:23328713

Esteves, Catarina V; Lima, Luís M P; Mateus, Pedro; Delgado, Rita; Brandão, Paula; Félix, Vítor

2013-05-01

15

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.)are earths. (orig.)

16

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

17

X-ray structural study of lanthanide complexes with a p- tert-butylthiacalix[4]arene bearing phosphoryl pendant arms  

Science.gov (United States)

A new lower-rim substituted thiacalix[4]arene, 5,11,17,23-tetra- tert-butyl-25,26,27,28-tetrakis(diphenylphosphinoylmethoxy) thiacalix[4]arene ( L) has been synthesized and structurally characterized as an adduct L·0.5MeOH·1.5H 2O, monoclinic, space group P2 1/n . The ligand adopts a cone conformation. Trivalent lanthanide ion complexes of this ligand have been synthesized and characterized by elemental analysis and IR spectra. The crystal structures of La 3+ and Nd 3+ complexes were determined by X-ray diffraction method. They are isostructural and belong to tetragonal system, I4 1/acd space group. In each complex, the calixarene retains the cone conformation, the metal ion is nine-coordinated to four oxygen atoms from phosphine oxide substituents, four oxygen atoms from two bidentate nitrate anions and one oxygen atom from a hydroxyl ion. The coordination polyhedron is a single-capped square antiprism. The complex assembles to a novel infinitely 1D helical structure through ?-? stacking, and further crosses each other forming a nanometer scale chessboard-like pore structure along c direction.

Guo, Qian-Ling; Yuan, Da-Qiang; Ma, Shu-Lan; Liu, Ying-Chun; Zhu, Wen-Xiang

2005-10-01

18

Synthesis and coordination properties of quinoline pendant arm derivatives of [9]aneN(3) and [9]aneN(2)S as fluorescent zinc sensors.  

Science.gov (United States)

The coordination chemistry of three new quinoline pendant arm derivatives of [9]aneN(3) (L(1), L(2)) and [9]aneN(2)S (L(3)) toward Cu(II), Zn(II), Cd(II), Hg(II), and Pb(II) has been investigated both in solution and in the solid state. The protonation constants for L(1)-L(3) and stability constants with the aforementioned metal ions have been determined potentiometrically in 0.10 M NMe(4)Cl MeCN/H(2)O (1:1 v/v) solution at 298.1 +/- 0.1 K; the measured values show that Cu(II) has the highest affinity for all three ligands, followed by Zn(II), Hg(II), Pb(II), and Cd(II). For each metal ion considered, 1:1 complexes with L(1)-L(3) have also been isolated in the solid state and [Cu(L(1))](BF(4))(2) (1), [Zn(L(1))](BF(4))(2) (2), [Cd(L(1))](ClO(4))(2) (3), [Hg(L(1))](NO(3))(2) (4), [Pb(L(1))](ClO(4))(2) x MeCN (5), [Zn(2)Cl(2)(L(2))(2)](BF(4))(2) x 1/2 MeNO(2) x H(2)O (6), [Cu(L(3))](ClO(4))(2) (7), [Zn(L(3))(NO(3))]NO(3) (8), [Cd(L(3))(NO(3))(0.82)Cl(0.18)]NO(3) (9), and [Hg(L(3))](ClO(4))(2) x MeCN (10) have also been characterized by X-ray crystallography. The optical response of L(1)-L(3) to the presence of the above-mentioned metal ions has been investigated in MeCN/H(2)O (1:1 v/v) and H(2)O solutions. All three ligands show a stronger "OFF-ON" CHEF (chelation enhancement of fluorescence) effect in the Zn(II) complexes than in the Cd(II) complexes in both media. The results have been examined by considering the ratio I(rel)(Zn(II))/I(rel)(Cd(II)), within the emerging idea that the relative strength of the CHEF effect for the small Zn(II) ion as compared to larger Cd(II) ion might be determined by steric crowding in the corresponding complexes with quinoline-based fluorescent chemosensors. PMID:19746898

Mameli, Marta; Aragoni, M Carla; Arca, Massimiliano; Atzori, Marta; Bencini, Andrea; Bazzicalupi, Carla; Blake, Alexander J; Caltagirone, Claudia; Devillanova, Francesco A; Garau, Alessandra; Hursthouse, Michael B; Isaia, Francesco; Lippolis, Vito; Valtancoli, Barbara

2009-10-01

19

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

20

Determination of cobalt ions at nano-level based on newly synthesized pendant armed macrocycle by polymeric membrane and coated graphite electrode.  

Science.gov (United States)

Poly(vinylchloride) (PVC) based membranes of macrocycles 2,3,4:9,10,11-dipyridine-1,3,5,8,10,12-hexaazacyclotetradeca-2,9-diene (L(1)) and 2,3,4:9,10,11-dipyridine-1,5,8,12-tetramethylacrylate-1,3,5,8,10,12-hexaazacyclotetradeca-2,9-diene (L(2)) with NaTPB and KTpClPB as anion excluders and dibutylphthalate (DBP), benzyl acetate (BA), dioctylphthalate (DOP), o-nitrophenyloctyl ether (o-NPOE) and tri-n-butylphosphate (TBP) as plasticizing solvent mediators were prepared and investigated as Co(2+) selective electrodes. The best performance was observed with the membranes having the composition L(2):PVC:TBP:NaTPB in the ratio of 6:39:53:2 (w/w; mg). The performance of the membrane based on L(2) was compared with polymeric membrane electrode (PME) and coated graphite electrode (CGE). The PME exhibits detection limit of 4.7x10(-8)M with a Nernstian slope of 29.7 mV decade(-1) of activity between pH 2.5 and 8.5 whereas CGE exhibits the detection limit of 6.8x10(-9)M with a Nernstian slope of 29.5 mV decade(-1) of activity between pH 2.0 and 9.0. The response time for PME and CGE was found to be 11 and 8s, respectively. The CGE has been found to work satisfactorily in partially non-aqueous media up to 35% (v/v) content of methanol, ethanol and 25% (v/v) content of acetonitrile and could be used for a period of 4 months. The CGE was successfully applied for the determination of Co(2+) in real and pharmaceutical samples and as an indicator electrode in potentiometric titration of cobalt ion. PMID:19836538

Singh, Ashok K; Singh, Prerna; Bhattacharjee, G

2009-12-15

21

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  

OpenAIRE

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

22

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

Science.gov (United States)

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

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

2007-04-28

23

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

24

Synthesis and reactivity of tripodal complexes containing pendant bases.  

Science.gov (United States)

The synthesis of a new tripodal ligand family that contains tertiary amine groups in the second-coordination sphere is reported. The ligands are tris(amido)amine derivatives, with the pendant amines attached via a peptide coupling strategy. They were designed to function as new molecular catalysts for the oxygen reduction reaction (ORR), in which the pendant acid/base group could improve the catalyst performance. Two members of the ligand family were each metalated with cobalt(II) and zinc(II) to afford trigonal-monopyramidal complexes. The reaction of the cobalt complexes [Co(L)](-) with dioxygen reversibly generates a small amount of a cobalt(III) superoxo species, which was characterized by electron paramagnetic resonance (EPR) spectroscopy. Protonation of the zinc complex Zn[N{CH2CH2NC(O)CH2N(CH2Ph)2}3)](-) ([Zn(TN(Bn))](-)) with 1 equiv of acid occurs at a primary-coordination-sphere amide moiety rather than at a pendant basic site. The addition of excess acid to any of the complexes [M(L)](-) results in complete proteolysis and formation of the ligands H3L. These undesired reactions limit the use of these complexes as catalysts for the ORR. An alternative ligand with two pyridyl arms was also prepared but could not be metalated. These studies highlight the importance of the stability of the primary-coordination sphere of ORR electrocatalysts to both oxidative and acidic conditions. PMID:25105991

Blacquiere, Johanna M; Pegis, Michael L; Raugei, Simone; Kaminsky, Werner; Forget, Amélie; Cook, Sarah A; Taguchi, Taketo; Mayer, James M

2014-09-01

25

Synthesis and photooxidation of styrene copolymer bearing camphorquinone pendant groups  

Directory of Open Access Journals (Sweden)

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

Branislav Husár

2012-03-01

26

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

Science.gov (United States)

Zinc complexes bearing the anilido-aldiminate AA(OMe) ligand (AA(OMe)-H = (E)-2,6-diisopropyl-N-(2-(((2-methoxyethyl)imino)methyl)phenyl)aniline) were synthesized in a stepwise method and were structurally characterized. The reaction of AA(OMe)-H (1) with one equivalent of diethyl zinc (ZnEt2) furnishes a three-coordinated and mononuclear zinc complex [(AA(OMe))ZnEt] (2). Further reaction of 2 with a stoichiometric amount of benzyl alcohol (BnOH) affords a four-coordinated and dinuclear zinc benzylalkoxide complex [(AA(OMe))Zn(?-OBn)]2 (3). In the presence of two equivalents of AA(OMe)-H with ZnEt2, a homoleptic and four-coordinated zinc complex [(AA(OMe))2Zn] (4) is formed. The geometry around the zinc centres of 3 and 4 are both distorted tetrahedrals, while 2 adopts a different coordination mode with a slightly distorted trigonal planar geometry. The variable-temperature (1)H NMR studies of 3 illustrate that 3 exhibits a dinuclear structure in solution at low temperature as well as in the solid state. While raising the temperature, it drifts towards dissociation to form a mononuclear zinc benzylalkoxide species, which coexists in solution. The ring-opening polymerizations of ?-caprolactone (?-CL) and ?-butyrolactone (?-BL) catalyzed by complexes 3 and 4 are investigated. The ?-CL and ?-BL polymerizations initiated by zinc alkoxide 3 were demonstrated to have living characteristics and to proceed in a controlled manner with narrow polydispersity indices (PDIs < 1.12). An efficient catalytic performance for the ?-BL polymerization with a high monomer-to-initiator ratio (1200/1) initiated by 3 has also been reported. PMID:23797573

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

2013-08-14

27

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

OpenAIRE

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

28

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

29

New polymeric biocides: synthesis and antibacterial activities of polycations with pendant biguanide groups.  

OpenAIRE

Acrylate monomers with pendant biguanide groups were successfully synthesized, and their homopolymers and copolymers were prepared with acrylamide. These cationic disinfectants of polymeric forms exhibited high antibacterial activity against gram-positive bacteria, whereas they were less active against gram-negative bacteria. It was found that the activity of the polymeric disinfectants was much higher than that of the monomeric species, and the difference in activity between the polymers and...

Ikeda, T.; Yamaguchi, H.; Tazuke, S.

1984-01-01

30

Synthesis and Reactivity of Tripodal Complexes Containing Pendant Bases  

Energy Technology Data Exchange (ETDEWEB)

The synthesis of a new tripodal ligand family is reported, with tertiary-amine groups in the second-coordination sphere. The ligands are tris(amido)amine derivatives, with the pendant amines attached via a peptide coupling strategy. They were designed to be used in new catalysts for the oxygen reduction reaction (ORR), in which the pendant acid/base group could improve catalyst performance. Two members of the new ligand family were each metallated with Co(II) and Zn(II) to afford trigonal monopyramidal complexes. Reaction of the cobalt complexes, [Co(L)]-, with dioxygen reversibly generates a small amount of a Co(III)-superoxo species, which was characterized by EPR. Protonation of the zinc complex Zn[N{CH2CH2NC(O)CH2N(CH2Ph)2}3)-– ([Zn(TNBn)]-) with one equivalent of acid occurs with displacement and dissociation of an amide ligand. Addition of excess acid to the any of the complexes [M(L)]- results in complete proteolysis and formation of the ligands H3L. This decomposition limits the use of these complexes as catalysts for the ORR. An alternative ligand with two pyridyl arms was also prepared but could not be metallated. These studies highlight the importance of stability of the primary-coordination sphere of ORR electrocatalysts to both oxidative and acidic conditions. 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.

Blacquiere, Johanna M.; Pegis, Michael L.; Raugei, Simone; Kaminsky, Werner; Forget, Amelie; Cook, Sarah; Taguchi, Taketo; Borovik, Andrew S.; Mayer, James M.

2014-09-02

31

Fluorescent macrocyclic probes with pendant functional groups as markers of acidic organelles within live cells.  

Science.gov (United States)

A new family of acidity sensitive fluorescent macrocycles has been synthesized and fully characterized. Their photophysical properties including emission quantum yield and fluorescence lifetime have been determined. The acid-base properties of the new molecules can be tuned by the incorporation of pendant functional groups. The nature of such functional groups (carboxylic acid or ester) influences dramatically the pKa of the probes, two compounds of which exhibit low values. Preliminary intracellular studies using confocal microscopy together with emission spectra of the probes from the cellular environment have shown that the synthesized fluorescent macrocycles mark the acidic organelles of RAW 264.7 macrophage cells. PMID:24317276

Wadhavane, Prashant D; Izquierdo, M Ángeles; Lutters, Dennis; Burguete, M Isabel; Marín, María J; Russell, David A; Galindo, Francisco; Luis, Santiago V

2014-02-01

32

A novel poly(aryl ether) containing azobenzene chromophore and pendant oligoaniline: Synthesis and electrochromic properties  

International Nuclear Information System (INIS)

Graphical abstract: This work describes a novel poly(aryl ether) functionalized with azobenzene chromophore and pendant oligoaniline, that exhibits a satisfied electrochromic properties with high contrast value, good coloration efficiency, moderate switching times and acceptable stability. - Abstract: A novel poly(aryl ether), containing pendant oligoaniline and azobenzene moieties (Azo-PAE-p-OA), was synthesized by nucleophilic polycondensation. The structures were confirmed spectroscopically via nuclear magnetic resonance (NMR) and Fourier-transform infrared spectra (FTIR), morphological data was ascertained via X-ray diffraction (XRD), and the thermal stability was probed via thermogravimetric analysis (TGA). Due to the coexistence of oligoaniline and azobenzene groups, Azo-PAE-p-OA shows reversible electroactivity and expectable photoresponse to light irradiation, chemical redox and electrochemical modulation. The electrochromic performance of a Azo-PAE-p-OA film on indium tin oxide (ITO) was investigated by spectrochronoamperometry, and exhibited electrochromic properties with high contrast value, good coloration efficiency, moderate switching times, and acceptable stability.

33

Accelerometer-based control of an industrial robotic arm  

OpenAIRE

Most of industrial robots are still programmed using the typical teaching process, through the use of the robot teach pendant. In this paper is proposed an accelerometer-based system to control an industrial robot using two low-cost and small 3-axis wireless accelerometers. These accelerometers are attached to the human arms, capturing its behavior (gestures and postures). An Artificial Neural Network (ANN) trained with a back-propagation algorithm was used to recognize arm ...

Neto, Pedro; Pires, Norberto; Moreira, Paulo

2013-01-01

34

Forces to Dislodge Rotating Sessile and Pendant Annular Rivulets  

Science.gov (United States)

In a recent PRL Tadmor, et al (2009) measured the lateral adhesion force on sessile and pendant drops (oil) of equal volume placed at R = 100 cm on a rotating flat surface (treated mica substrate) and found that more force is required to radially displace the pendant drops. This was explained as enhanced chemical interaction between liquid and solid molecules when the drop is pendant compared to sessile. We take the view it is primarily static advancing and receding contact angles that govern the movement of the drops. This is shown by a simple model where the isolated drop is replaced by a thin axisymmetric rivulet. For realistic advancing and receding contact angles of water on anodized aluminum, computations performed show the existence of four distinct regions governing drop movement. The three regions found at small radii give way at R = 2.0 cm to the final fourth region where drop movement depends on the advancing contact angle for both sessile and pendant drops; here the pendant drops require a larger radial force to dislodge, in agreement with the mesurements of Tadmor, et al. Simulations more closely mimicking the experiments of Tadmor, et al will be presented.

Weidman, P. D.; Malhotra, C. P.

2010-11-01

35

Polythiophenes Comprising Conjugated Pendants for Polymer Solar Cells: A Review  

Directory of Open Access Journals (Sweden)

Full Text Available Polythiophene (PT is one of the widely used donor materials for solution-processable polymer solar cells (PSCs. Much progress in PT-based PSCs can be attributed to the design of novel PTs exhibiting intense and broad visible absorption with high charge carrier mobility to increase short-circuit current density (Jsc, along with low-lying highest occupied molecular orbital (HOMO levels to achieve large open circuit voltage (Voc values. A promising strategy to tailor the photophysical properties and energy levels via covalently attaching electron donor and acceptor pendants on PTs backbone has attracted much attention recently. The geometry, electron-donating capacity, and composition of conjugated pendants are supposed to be the crucial factors in adjusting the conformation, energy levels, and photovoltaic performance of PTs. This review will go over the most recent approaches that enable researchers to obtain in-depth information in the development of PTs comprising conjugated pendants for PSCs.

Hsing-Ju Wang

2014-03-01

36

Ionic polymer cluster energetics: Computational analysis of pendant chain stiffness and charge imbalance  

International Nuclear Information System (INIS)

In recent years there has been considerable study of the potential mechanisms underlying the electromechanical response of ionic-polymer-metal composites. The most recent models have been based on the response of the ion-containing clusters that are formed when the material is synthesized. Most of these efforts have employed assumptions of uniform ion distribution within spherical cluster shapes. This work investigates the impact of dispensing with these assumptions in order to better understand the parameters that impact cluster shape, size, and ion transport potential. A computational micromechanics model applying Monte Carlo methodology is employed to predict the equilibrium state of a single cluster of a solvated ionomeric polymer. For a constant solvated state, the model tracks the position of individual ions within a given cluster in response to ion-ion interaction, mechanical stiffness of the pendant chain, cluster surface energy, and external electric-field loading. Results suggest that cluster surface effects play a significant role in the equilibrium cluster state, including ion distribution; pendant chain stiffness also plays a role in ion distribution but to a lesser extent. Moreover, ion pairing is rarely complete even in cation-rich clusters; this in turn supports the supposition of the formation of anode and cathode boundary layers

37

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

Energy Technology Data Exchange (ETDEWEB)

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

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

2008-01-01

38

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

39

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.

40

Robotic arm  

Science.gov (United States)

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

Kwech, Horst (Lake Bluff, IL)

1989-04-18

41

Robotic arm  

International Nuclear Information System (INIS)

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

42

A Novel Side-Bridged Hybrid Phosphonate/Acetate Pendant Cyclam: Synthesis, Characterization, and 64Cu Small Animal PET Imaging  

OpenAIRE

Copper-64 (t½ = 12.7 hr; ?+: 0.653 MeV, 17.4%; ??: 0.578 MeV, 39%) is produced in a biomedical cyclotron and has applications in both imaging and therapy. Macrocyclic chelators are widely used as bifunctional chelators to bind copper radionuclides to antibodies and peptides owing to their relatively high kinetic stability. A novel side-bridged cyclam featuring both pendant acetate and phosphonate groups was synthesized using a Kabachnik-Fields approach followed by hydrobromic acid deprot...

Boswell, C. Andrew; Regino, Celeste A. S.; Baidoo, Kwamena E.; Wong, Karen J.; Milenic, Diane E.; Kelley, James A.; Lai, Christopher C.; Brechbiel, Martin W.

2009-01-01

43

Metallographic analysis of 3000-year-old Kanalski Vrh hoard pendant  

International Nuclear Information System (INIS)

In a Late Bronze Age hoard at Kanalski Vrh in Slovenia, bronze pendants were found among numerous other artifacts. Among them a group of nine pendants of very similar compositions contained higher amounts of antimony, arsenic, nickel, cobalt, and iron, which suggested that speiss was added to bronze. Furthermore, most pendants had a silvery grey surface that differed from the common color of tin bronze, with about 13% Sn. One of the pendants was analysed by light optical and electron microscopy, Auger electron spectroscopy (AES), X-ray diffraction (XRD), and differential thermal analysis (DTA). Analyses revealed that the surface of the pendant was corroded, the copper alpha phase was eaten away, and the remaining eutectoid phase exhibited that silvery grey color. Comparison of chemical composition of the pendant and of compositions of speiss ingots found in the same hoard indicated that speisses could be used as alloying additions in making melts for casting pendants

44

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

45

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

Energy Technology Data Exchange (ETDEWEB)

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

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

2009-01-01

46

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

47

Waveform synthesizer  

International Nuclear Information System (INIS)

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

48

Waveform synthesizer  

Science.gov (United States)

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

49

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 gs 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.

50

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

Energy Technology Data Exchange (ETDEWEB)

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.

Grattan, Mark W. D.; McGarry, Conor K. [Radiotherapy Physics, Belfast Health and Social Care Trust, Northern Ireland Cancer Centre, Belfast City Hospital Site, Lisburn Road, Belfast BT9 7AB Northern Ireland (United Kingdom)

2010-04-15

51

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)

52

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

53

Gravity model and structural implications of the Goddard Pendant, Sierra Nevada, California.  

Science.gov (United States)

A subsurface model for the Goddard pendant is constructed from a residual gravity high of about 7mGal over the pendant. The model, which is the simplest and most geologically reasonable possibility, shows a metamorphic block that tapers with depth and extends about 3.5km below the surface. The structures in the Goddard pendant are similar in style and orientation to those in other Sierra Nevada pendants, indicating that the country rock was neither deformed nor rotated during pluton emplacement. Consequently, emplacement must have been a passive rather than a forceful process. The pendant itself represents a piece of country rock trapped between plutons which are dome shaped in cross section. -Authors

du Bray, E.A.; Oliver, H.W.

1981-01-01

54

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

55

Oligomers with pendant isocyanate groups as tissue adhesives. I. Synthesis and characterization.  

Science.gov (United States)

A series of methacrylate oligomers containing pendant isocyanate groups were synthesized by reacting 2-isocyanatoethyl methacrylate (IEM) and/or m-isopropenyl-alpha, alpha-dimethylbenzyl isocyanate (TMI) in ethoxyethyl acetate with methacrylates ranging from methyl to stearyl methacrylate or allyl-, cyclohexyl-, glycidyl-, i-bornyl-, or dicyclopentenyloxyethyl methacrylate. The oligomers which are stable at room temperature were characterized by IR for NCO, ester, and C = C groups and by their refractive indices. They have a small number of residual double bonds and a molecular weight low enough so that the compounds are liquids at room temperature and dissolve readily in esters and chlorinated hydrocarbons. HPLC showed no residual monomer. GPC and intrinsic viscosity of selected oligomers indicated a molecular weight range from 1400 to 2600. Isocyanate groups were determined titrimetrically and ranged from 15.9% to 5.1%. Concurrent studies have demonstrated that these oligomers bond strongly to hard and soft tissues. Thus, subject to their biocompatibility they could find many applications as tissue adhesives. PMID:2715156

Brauer, G M; Lee, C H

1989-03-01

56

Preparation and Characterization of Maltose-Pendant Polymer/Mica Nanocomposites and Their Application to Oxygen Gas Barrier Films  

OpenAIRE

Maltose-pendant polymer/mica nanocomposites were prepared by a solution intercalation method. For organic composite part, 1) maltose-pendant polymer (homopolymer) and 2) the copolymer of maltose-pendant monomer and a small amount of N,N

Hideo Sakurai; Shoji Nagaoka; Maki Horikawa; Tomohiro Shirosaka; Shuzou Kubota; Kazuhiro Hamada; Makoto Takafuji; Hirotaka Ihara

2014-01-01

57

On the Odd Gracefulness of Cyclic Snakes With Pendant Edges  

Directory of Open Access Journals (Sweden)

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

E. M. Badr

2013-01-01

58

Layered inorganic/organic mercaptopropyl pendant chain hybrid for chelating heavy cations  

International Nuclear Information System (INIS)

Graphical abstract: Crystalline lamellar silicate RUB-18 was immobilized with mercaptopropyl groups at the surface and then used as support for cadmium and lead removal from aqueous solutions. Highlights: ? Synthetic methodology requires intercalation. ? Organofunctionalized ilerite compound as sorbent. ? Active mercaptopropyl groups remove cations. ? High maximum sorption capacity for cadmium. -- Abstract: Heavy metal sorbents with uptake capacities for divalent cadmium and lead cation removal from aqueous solutions have been synthesized by grafting mercaptopropyltrimethoxysilane onto the surface of two different precursors obtained from lamellar ilerite, its acidic and the cetyltrimethylammonium exchanged forms. The organofunctionalization was carried out by two different procedures: reflux and solvent evaporation methodologies. Elemental analysis data based on carbon content gave 1.37 and 3.53 mmol of organic pendant groups per gram of hybrid by the reflux method, when starting from acidic ilerite and the surfactant form. X-ray diffraction corroborated the maintenance of the original crystallinity. Infrared spectroscopy and nuclear magnetic resonance for 29Si and 13C nuclei are in agreement with the success of the proposed method. The sulfur basic centers attached to the lamellar structure are used to coordinate both cations at the solid/liquid interface. The isotherms were obtained through the batchwise process and the experimental data were adjusted to the Freundlich model. The maximum sorption capacities of 5.55 and 5.12 mmol g?1 for lead and 6.10 and 7.10 mmol g?1 for cadmium were obtained for organofunctionalized ilerite and its surfactant form, synthesized by reflux methodology. This behavior suggested that these hybrids could be employed as promising sorbents with a polluted system.

59

Layered inorganic/organic mercaptopropyl pendant chain hybrid for chelating heavy cations  

Energy Technology Data Exchange (ETDEWEB)

Graphical abstract: Crystalline lamellar silicate RUB-18 was immobilized with mercaptopropyl groups at the surface and then used as support for cadmium and lead removal from aqueous solutions. Highlights: Black-Right-Pointing-Pointer Synthetic methodology requires intercalation. Black-Right-Pointing-Pointer Organofunctionalized ilerite compound as sorbent. Black-Right-Pointing-Pointer Active mercaptopropyl groups remove cations. Black-Right-Pointing-Pointer High maximum sorption capacity for cadmium. -- Abstract: Heavy metal sorbents with uptake capacities for divalent cadmium and lead cation removal from aqueous solutions have been synthesized by grafting mercaptopropyltrimethoxysilane onto the surface of two different precursors obtained from lamellar ilerite, its acidic and the cetyltrimethylammonium exchanged forms. The organofunctionalization was carried out by two different procedures: reflux and solvent evaporation methodologies. Elemental analysis data based on carbon content gave 1.37 and 3.53 mmol of organic pendant groups per gram of hybrid by the reflux method, when starting from acidic ilerite and the surfactant form. X-ray diffraction corroborated the maintenance of the original crystallinity. Infrared spectroscopy and nuclear magnetic resonance for {sup 29}Si and {sup 13}C nuclei are in agreement with the success of the proposed method. The sulfur basic centers attached to the lamellar structure are used to coordinate both cations at the solid/liquid interface. The isotherms were obtained through the batchwise process and the experimental data were adjusted to the Freundlich model. The maximum sorption capacities of 5.55 and 5.12 mmol g{sup -1} for lead and 6.10 and 7.10 mmol g{sup -1} for cadmium were obtained for organofunctionalized ilerite and its surfactant form, synthesized by reflux methodology. This behavior suggested that these hybrids could be employed as promising sorbents with a polluted system.

Macedo, Thais R. [Institute of Chemistry, University of Campinas, UNICAMP, P.O. Box 6154, 13084-71 Campinas, SP (Brazil); Petrucelli, Giovanni C. [Institute of Chemistry, Federal University of Goias, Jatai, P.O. Box 03, 75805-190 Jatai, GO (Brazil); Pinto, Alane A. [Institute of Chemistry, University of Campinas, UNICAMP, P.O. Box 6154, 13084-71 Campinas, SP (Brazil); Institute of Chemistry, Federal University of Goias, Jatai, P.O. Box 03, 75805-190 Jatai, GO (Brazil); Airoldi, Claudio, E-mail: airoldi@iqm.unicamp.br [Institute of Chemistry, University of Campinas, UNICAMP, P.O. Box 6154, 13084-71 Campinas, SP (Brazil)

2011-12-15

60

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

61

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

62

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

International Nuclear Information System (INIS)

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: ? The side-functional moieties of pBVMA regularly arranged in film state. ? The device exhibits volatile memory behavior with an ON/OFF current ratio up to 105. ? The film thickness has nothing to do with the device's memory behavior. ? 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 105 and can endure 108 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 etical models were analyzed and the mechanism of the DRAM performance may be attributed to the weak electron withdrawing ability of the molecule.

63

Strong-Arm Tactics  

Science.gov (United States)

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

Integrated Teaching And Learning Program

64

Les trotskystes grecs pendant la seconde guerre Mondiale  

Directory of Open Access Journals (Sweden)

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

Alexis Hen

2011-11-01

65

Chemical and biological sensing through optical resonances in pendant droplets  

Science.gov (United States)

A microdroplet can act as a high quality factor optical cavity that supports Morphology Dependent Resonances(MDRs). Enhanced radiative energy transfer through these optical resonances can also be utilized as a transduction mechanism for chemical and biological sensing. Enhancement in radiative energy transfer is observed when a donor/acceptor pair is present in the resonant medium of a microcavity. Here, we demonstrate avidin-biotin binding and its detection through a FRET pair as a potential application for ultra-sensitive detection for fluoroimmunoassays. The binding interaction between the biotinylated donor molecules and streptavidin-acceptor conjugate was used to observe the energy transfer between the dye pairs. The radial modes of MDRs extend to approximately 0.6 r 0 inside the droplet. As a result, the fluorescent emission around the center is not coupled to the optical resonances losing sensitivity. To address this problem, we prepared water-in-oil emulsions of avidin and biotin containing solutions. The water phase contains the streptavidin-Alexa Fluor 610 and the oil phase contains biotinylated fluorescent bead. Streptavidin-biotin binding reaction occurs at the water-oil interface. The water phase accumulates at the droplet air interface due to higher specific density enhancing the resonance coupling. Water and oil phase are index-matched to avoid scattering problems. As a result, a large portion of the avidin-biotin complex was localized at the pendant droplet and air interface. Strong coupling of acceptor emission into optical resonances shows that the energy transfer is efficiently mediated through these resonances.

Tanyeri, Melikhan; Dosev, Dosi; Kennedy, Ian M.

2005-11-01

66

Controlled Synthesis of Fluorinated Copolymers with Pendant Sulfonates  

DEFF Research Database (Denmark)

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

Dimitrov, Ivaylo; Jankova Atanasova, Katja

2008-01-01

67

Design and Engineering of a Chess-Robotic Arm  

CERN Document Server

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

Elouafiq, Ali

2012-01-01

68

Arm MRI scan  

Science.gov (United States)

... An abnormal finding on an x-ray or bone scan Arm pain and a history of cancer Arm or wrist pain that does not get better with treatment Bone infection (osteomyelitis) Bone pain and fever Broken bone ...

69

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

Science.gov (United States)

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

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

2012-05-01

70

Nuclear Arms Control Treaties  

Science.gov (United States)

This section contains summaries of all the major arms-control treaties including: Limited Test Ban Treaty, Nuclear Non-Proliferation Treaty, Strategic Arms Limitation Treaty I (Interim Agreement), Anti-Ballistic Missile Treaty, Threshold Test Ban Treaty, Intermediate-Range Nuclear Forces Treaty - INF, Strategic Arms Reduction Treaty, Comprehensive Test Ban Treaty and Strategic Offensive Reductions Treaty.

Christopher Griffith

71

Non-Destructive investigation of a scalenohedral hematite pendant from Bahrain, c. 1800 BC  

DEFF Research Database (Denmark)

A scalenohedral hematite pendant (presumably a pseudomorph after a calcite crystal), excavated on Bahrain (ancient Dilmun) in the Persian Gulf from layers dated to c.1800 bc, was investigated using X-ray computed microtomography. The internal porosity was studied in 3D, showing a preferential concentration of small pores in the central part, where carbonate remnants might still be present, and larger, flattened, elongated voids in the subsurface portion. Part of the scalenohedron can be described as an intergrowth of platy hematite crystals. Microtomography also yielded data on pore-size distribution. Considerations are given to the genetic model and the provenance of the hematite pendant.

Makovicky, Emil; Parisatto, Matteo

2015-01-01

72

Synthesis and photooxidation of styrene copolymer bearing camphorquinone pendant groups  

OpenAIRE

(±)-10-Methacryloyloxycamphorquinone (MCQ) was synthesized from (±)-10-camphorsulfonic acid either by a known seven-step synthetic route or by a novel, shorter five-step synthetic route. MCQ was copolymerized with styrene (S) and the photochemical behavior of the copolymer MCQ/S was compared with that of a formerly studied copolymer of styrene with monomers containing the benzil (BZ) moiety (another 1,2-dicarbonyl). Irradiation (? > 380 nm) of...

Branislav Husár; Norbert Moszner; Ivan Luká?

2012-01-01

73

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

74

Quenching of excited state of polymer-pendant Ru(bpy)32+ by methylviologen  

International Nuclear Information System (INIS)

Copolymer pendant tris(2,2'-bipyridine)ruthenium(II) (Ru(bpy)32+) complexes were prepared, and the quenchings of their excited state with methylviologen (MV2+) were studied. The quenching rate constant of the excited state of copolymer pendant Ru(bpy)32+ 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 MV2+, 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)

75

Le discours sur «l'étranger» pendant la Terreur, 5 nivôse - 9 thermidor an II  

OpenAIRE

La cartographie des occurrences discursives émises par les différents producteurs d’opinion publique pendant la Révolution française permet de saisir les formes et les déterminations du discours tenu sur l’étranger du 5 nivôse au 9 thermidor an II. On constate alors que ce discours peut obéir soit à des logiques de voisinage guerrier soit à des logiques politiques.

Wahnich, Sophie; The?ry, Herve?

1995-01-01

76

Magnetic Properties of Iron(III Complexes with Pendant-Armed Alcohols of 1, 4, 7, 10-Tetraazacyclododecane (Cyclen Ligands.  

Directory of Open Access Journals (Sweden)

Full Text Available The magnetic properties of the compounds [Fe{H2THED}(FeCl3]Cl (1, [Fe3(TRED2(N32]Cl.5H2O (2 and [Fe4O2(1,4-DHED2(N34] 6MeOH (3 are reported (H4THED is (1,4,7,10-tetrakis(2-hydroxyethyl-1,4,7,10- tetraazacyclododecane, (H3TRED is 1,4,7-tris (2-hydroxyethyl-1,4,7,10-tetraazacyclododecane and (H2DHED is (1,4-bis (2-hydroxyethyl-1,4,7,10-tetraazacyclododecane. Variable temperature magnetic susceptibilty measurements of 1, 3 complexes possess S = 0 spin ground states, while 2 has an S = 2 spin ground state.

Abd-Alhakeem H. Abu-Nawwas

2014-02-01

77

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

78

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

79

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 potentiusage 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.

80

Role of Hydrophilicity and Length of Diblock Arms for Determining Star Polymer Physical Properties.  

Science.gov (United States)

We present a molecular simulation study of star polymers consisting of 16 diblock copolymer arms bound to a small adamantane core by varying both arm length and the outer hydrophilic block when attached to the same hydrophobic block of poly-?-valerolactone. Here we consider two biocompatible star polymers in which the hydrophilic block is composed of polyethylene glycol (PEG) or polymethyloxazoline (POXA) in addition to a polycarbonate-based polymer with a pendant hydrophilic group (PC1). We find that the different hydrophilic blocks of the star polymers show qualitatively different trends in their interactions with aqueous solvent, orientational time correlation functions, and orientational correlation between pairs of monomers of their polymeric arms in solution, in which we find that the PEG polymers are more thermosensitive compared with the POXA and PC1 star polymers over the physiological temperature range we have investigated. PMID:25254622

Felberg, Lisa E; Brookes, David H; Head-Gordon, Teresa; Rice, Julia E; Swope, William C

2014-09-25

81

Robot Arm Tutorial  

Science.gov (United States)

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

2012-03-15

82

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

83

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 each) 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 groups must work to communicate effectively through written and verbal communication and sketches.

2014-09-18

84

Arms control and disarmament  

International Nuclear Information System (INIS)

Article VI of the Non-Proliferation Treaty commits each party to work towards nuclear disarmament and to negotiations to stop the nuclear arms race. All parties to the Treaty are included and a wide range of arms control and disarmament issues are covered. However the main focus at Treaty review conferences has been on nuclear disarmament by the nuclear weapon states which are party to the Treaty. This has led to bilateral United States - Soviet Union negotiations resulting in the Intermediate-range Nuclear Forces Treaty in December 1987 and the Strategic Arms Reduction Treaty (START) in July followed by unilateral arms control measures in September and October 1991. (UK)

85

Inorganic syntheses, v.38  

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.

Shriver, Duward F

2009-01-01

86

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

87

Portable Speech Synthesizer  

Science.gov (United States)

Compact speech synthesizer useful traveling companion to speech-handicapped. User simply enters statement on board, and synthesizer converts statement into spoken words. Battery-powered and housed in briefcase, easily carried on trips. Unit used on telephones and face-to-face communication. Synthesizer consists of micro-computer with memory-expansion module, speech-synthesizer circuit, batteries, recharger, dc-to-dc converter, and telephone amplifier. Components, commercially available, fit neatly in 17-by 13-by 5-in. briefcase. Weighs about 20 lb (9 kg) and operates and recharges from ac receptable.

Leibfritz, Gilbert H.; Larson, Howard K.

1987-01-01

88

Role of pendant proton relays and proton-coupled electron transfer on the hydrogen evolution reaction by nickel hangman porphyrins  

OpenAIRE

The conversion of solar energy into fuels involves coupled multiproton–multielectron reactions. Because of different length scales for electron transfer and proton transfer, efficient catalysts must couple proton hops to redox events. We have developed a hangman motif where placing a pendant acid–base group over the face of a redox macrocycle ensures coupling of the electron to the proton. We now show that the presence of the pendant acid relay of a Ni hangman porphyrin facilitates proton...

Bediako, D. Kwabena; Solis, Brian H.; Dogutan, Dilek K.; Roubelakis, Manolis M.; Maher, Andrew G.; Lee, Chang Hoon; Chambers, Matthew B.; Hammes-schiffer, Sharon; Nocera, Daniel G.

2014-01-01

89

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

OpenAIRE

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...

Kwon, Hyukmin; Paxson, Adam T.; Varanasi, Kripa K.; Patankar, Neelesh A.

2010-01-01

90

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

91

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

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

2008-10-14

92

Absorption d'huile pendant la friture profonde: mécanismes et facteurs importants  

OpenAIRE

Cette recherche a été menée pour mieux comprendre l'imprégnation en huile pendant la friture profonde. La teneur en matière grasse élevée est un des caractéristiques critiques des produits frits. Malgré des efforts des scientifiques, les produits frits contiennent encore une quantité considérable de matière grasse. De nombreuses études expérimentales ont été réalisées afin de mettre en évidence par quels mécanismes, où et quand l'imprégnation en huile se passe lors du pr...

Ziaiifar, Aman Mohammad

2008-01-01

93

Expected length of pendant and interior edges of a Yule tree  

OpenAIRE

The Yule (pure-birth) model is the simplest null model of speciation; each lineage gives rise to a new lineage independently with the same rate $\\lambda$. We investigate the expected length of an edge chosen at random from the resulting evolutionary tree. In particular, we compare the expected length of a randomly selected edge with the expected length of a randomly selected pendant edge. We provide some exact formulae, and show how our results depend slightly on whether the...

Steel, Mike; Mooers, Arne

2009-01-01

94

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

Science.gov (United States)

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

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

2009-12-01

95

Caractérisation expérimentale des émissions de pesticides vers l'air pendant les pulvérisations viticoles  

OpenAIRE

Des évaluations de pertes verticales du jet pendant une pulvérisation agricole assistée par air ont été effectuées en utilisant un traceur fluorescent et des lignes de PVC comme collecteurs. Des analyses par régression linéaire multiple et l'inférence par logique floue ont été employées pour évaluer les effets des conditions micro-climatiques sur deux spectres de tailles de gouttes (fine et très fine). Les modèles de régression multiple ont été établis pour chaque série d'...

Gil, Yvan

2007-01-01

96

ABOUT PRISMATIC ANTLER PENDANTS FROM SÂNTANA DE MURE?-CERNJACHOV CULTURE  

OpenAIRE

In Sântana de Mure?-Cernjachov culture we distinguish numerous influences that have targeted not only the material aspects of daily life but also the spiritual life of its different ethnic components. Since the IVth century are signaled in the graves of women and children a series of prismatic pendants made of antlers decorated with circles, which were seen by some scholars, such as J. Werner and I. Ionita as replicas of type Herkuleskeule amulets. They were adopted in the Germanic world ...

Ciuc?l?u Daniel

2014-01-01

97

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

98

MVACS Robotic Arm  

Science.gov (United States)

The primary purpose of the Mars Volatiles and Climate Surveyor (MVACS) Robotic Arm is to support to the other MVACS science instruments by digging trenches in the Martian soil; acquiring and dumping soil samples into the thermal evolved gas analyzer (TEGA); positioning the Soil Temperature Probe (STP) in the soil: positioning the Robotic Arm Air Temperature Sensor (RAATS) at various heights above the surface, and positioning the Robotic Arm Camera (RAC) for taking images of the surface, trench, soil samples, magnetic targets and other objects of scientific interest within its workspace.

Bonitz, R.; Slostad, J.; Bon, B.; Braun, D.; Brill, R.; Buck, C.; Fleischner, R.; Haldeman, A.; Herman, J.; Hertzel, M.; Noon, D.; Pixler, G.; Schenker, P.; Ton, T.; Tucker, C.; Zimmerman, W.

2000-01-01

99

Biphenyl derived Schiff-base vanadium(V) complexes with pendant OH-groups--structure, characterization and hydrogen peroxide mediated sulfide oxygenation.  

Science.gov (United States)

A series of mononuclear oxovanadium(v) complexes of tridentate Schiff bases HL(1)-HL(4) and H(2)L(5)-H(2)L(8) derived from 6-phenylsalicylaldehyde and 6-(2-hydroxyphenyl)salicylaldehyde and four different amines was synthesized. The systematically selected ligands contain aliphatic or aromatic nitrogen, or alkoxy- and phenoxy-oxygen as third donor atom. The complexes were characterised by spectroscopic methods in solution and the solid state. Single-crystal X-ray analyses were performed with VO(2)L(1)(), VO(2)L(3)x1/2EtOH (), VO(2)L(4)(), VO(OiPr)L(7)xiPrOH, VO(OiPr)L(8) and H(2)L(8). For all compounds the vanadium(v) cores contain distorted tetragonal pyramidal geometry around the dioxo- and oxovanadium site at which the N(2)O- and NO(2)-donor ligands bind equatorially. Complexes and display intramolecular hydrogen bonding of the pendant hydroxyphenyl group to a coordinated oxygen trans to a nitrogen atom and therefore serve as suitable models for the native site of vanadium dependent haloperoxidases. Variable-temperature (1)H NMR spectra revealed significant hydrogen bond interaction in acetonitrile solution. In situ prepared catalysts are active for hydrogen peroxide mediated oxygenation of ethyl phenyl sulfide and showed complete conversion of the substrate to ethyl phenyl sulfoxide, together with small amounts of the corresponding sulfone, as detected by GC/MS after 10 min. The complex of H(2)L(7) turned out to be most efficient while HL(1) and HL(2) were completely inactive. Catalysis is supported by the pendant OH group in the complex of HL(3), the catalyst is twice as active as the complex of HL(4). PMID:15278124

Plitt, Patrick; Pritzkow, Hans; Kramer, Roland

2004-08-01

100

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

101

Synthesis, helicity, and chromism of optically active poly(phenylacetylene)s carrying different amino acid moieties and pendant terminal groups.  

Science.gov (United States)

Functional phenylacetylene derivatives containing l-alanine and l-leucine moieties with chiral menthyl and achiral n-octyl terminal groups {HC[triple bond]C-C6H4-p-CONHCH(R)CO2R': R = CH3, R'= (-)-(1R,2S,5R)-menthyl [1(-)]; R = CH2CH(CH2)3, R' = (-)-(1R,2S,5R)-menthyl [2(-)]; R'= CH2CH(CH2)3, R' = (+)-(1S,2R,5S)-menthyl [2(+)]; R'= CH2CH(CH2)3, R' = (CH2)7CH3 (2o)} are synthesized. Polymerizations of the acetylene monomers are effected by organorhodium catalysts, giving corresponding polymers P1(-), P2(-), P2(+), and P2o of high molecular weights (Mw up to 1.2 x 10(6)) in high yields (up to 89%). The polymers are thermally stable (Td >or= 300 degrees C) and soluble in common organic solvents. The polymer structures are characterized by IR, NMR, UV, and CD spectroscopies. Intense CD signals are observed in the visible spectral region, indicating that the polymer chains are taking a helical conformation with an excess of preferred handedness. The backbone conjugation and chain helicity of the polymers can be tuned by changing their molecular structures [(a)chiral pendant groups] and by applying external stimuli (solvent and pH). Addition of trifluoroacetic acid to the polymer solutions decreases their molar ellipticities and enhances their backbone conjugations, inducing a halochromism with a continuous and reversible color change (yellow red). PMID:16771375

Lai, Lo Ming; Lam, Jacky W Y; Qin, Anjun; Dong, Yongqiang; Tang, Ben Zhong

2006-06-15

102

Synthesis and characterization of reversible chemosensory polymers: modulation of sensitivity through the attachment of novel imidazole pendants.  

Science.gov (United States)

Three novel electron donor-acceptor conjugated polymers (P1-P3) bearing various imidazole pendants have been synthesized. Their excellent photophysical and electrochemical properties make them suitable transduction materials for chemosensing applications. Indeed, polymers P1-P3 have been found to show remarkable sensing capabilities towards H(+) and Fe(2+) in semi-aqueous solutions. Upon titration with H(+), polymers P1 and P2 showed hypsochromic shifts of their absorptions and photoluminescence (PL) maxima with enhanced fluorescence intensities. However, P3 showed diminished absorption and fluorescence intensities under similar conditions due to static quenching. The anomalous behavior of P3 compared with P1 and P2 has been clarified in terms of electronic distributions through computational analysis. Furthermore, P3 (K(SV) = 1.03×10(7)) showed a superior sensing ability towards Fe(2+) compared with P1 (K(SV) = 2.01×10(6)) and P2 (K(SV) = 4.12×10(6)) due to its improved molecular wire effect. Correspondingly, the fluorescence lifetime of P3 was greatly decreased (almost 11-fold) compared to those of polymers P1 (4.6-fold) and P2 (6.2-fold) in the presence of Fe(2+). By means of a fluorescence on-off-on approach, chemosensing reversibilities in protonation-deprotonation and metallation-demetallation have been achieved by employing triethylamine (TEA) and the disodium salt of ethylenediaminetetraacetic acid (Na(2)-EDTA)/phenanthroline, respectively, as suitable counter ligands. (1)H?NMR titrations have revealed the unique behavior of P3 compared with P1 and P2. To the best of our knowledge, there have been no previous reports of Fe(2+) sensors based on single imidazole receptors conjugated to a main-chain polymer showing such a diverse sensitivity pattern depending on their attached substituents. PMID:23111823

Satapathy, Rudrakanta; Padhy, Harihara; Wu, Yen-Hsing; Lin, Hong-Cheu

2012-12-01

103

Arming device and method  

Energy Technology Data Exchange (ETDEWEB)

There is disclosed an arming and disarming device which is run into a well bore on a wireline and which is part of an explosive tool to conduct some type explosive operation in the well bore. In the disarmed configuration, the arming sub acts to separate the hot lead in the wireline from the explosive tool, to short circuit the hot and ground leads of the explosive well tool together and to connect the short circuited tool leads to ground. In one mode of use of the arming sub, hydrostatic pressure applied to the tool as it is being run into the well bore acts to move a piston inside the device. As the piston moves, the hot lead of the wireline is electrically connected to the short circuited hot and ground connections of the explosive tool. Continued movement of the piston breaks the short circuit between the hot and ground connections of the explosive tool thereby arming the tool.

Boop, G. T.

1981-05-12

104

Underreamer cutter arm  

Energy Technology Data Exchange (ETDEWEB)

A hole drilling tool, useful in mining operations for enlarging the lower portion of a hole for explosives, is described. This underreamer has arms movable between a retracted position and an extended position for under-reaming in response to weight of the drill string above the tool. The 2 cutter arms are urged outward into their extended position by a cam connected to the upper end of the drill string. In effect, the cutter arms are connected to the lower end of the drill string which can telescope relative to the upper end. An air-flow passage extends from the tool body through the cutter arms for cooling the cutter bearings. (12 claims)

Furse, J.H.

1976-04-13

105

External Resource: Robotic Arm  

Science.gov (United States)

In this activity, students will design and build their own rovers, explaining what type of instrumentation they would include and why it is necessary. Topics: engineering design, robots, end effectors, robotic arm, space exploration.

1900-01-01

106

Synthesis and characterization of novel sulfonated poly(arylene ether ketone) copolymers with pendant carboxylic acid groups for proton exchange membranes  

Energy Technology Data Exchange (ETDEWEB)

A series of novel side-chain-type sulfonated poly(arylene ether ketone)s with pendant carboxylic acid groups copolymers (C-SPAEKs) were synthesized by direct copolymerization of sodium 5,5'-carbonyl-bis(2-fluorobenzenesulfonate), 4,4'-difluorobenzophenone and 4,4'-bis(4-hydroxyphenyl) valeric acid (DPA). The expected structure of the sulfonated copolymers was confirmed by FT-IR and {sup 1}H NMR. Membranes with good thermal and mechanical stability could be obtained by solvent cast process. It should be noted that the proton conductivity of these copolymers with high sulfonatation degree (DS > 0.6) was higher than 0.03 S cm{sup -1} and increased with increasing temperature. At 80 C, the conductivity of C-SPAEK-3 (DS = 0.6) and C-SPAEK-4 (DS = 0.8) reached up to 0.12 and 0.16 S cm{sup -1}, respectively, which were higher than that of Nafion 117 (0.10 S cm{sup -1}). Moreover, their methanol permeability was much lower than that of Nafion 117. These results showed that the synthesized materials might have potential applications as the proton exchange membranes for DMFCs. (author)

Zhang, Yang; Zhao, Chengji; Shao, Ke; Li, Hongtao; Fu, Tiezhu; Na, Hui [Alan G MacDiarmid Institute, College of Chemistry, Jilin University, Changchun 130012 (China); Cui, Zhiming; Xing, Wei [Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022 (China)

2009-06-15

107

Armed conflict and child health  

OpenAIRE

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...

Rieder, Michael; Choonara, Imti

2012-01-01

108

Synthesis and Crystal Structures of Mercury(II) and Copper(II) Complexes of Azathia-Macrocycle with Pyridylmethyl Arm  

International Nuclear Information System (INIS)

Mercury(II) and copper(II) complexes of pyridylmethyl-armed monobenzo-NS2-macrocycle have been prepared and structurally characterized by X-ray analysis. In all cases, the pyridine arms show important role in their three dimensional coordination behaviors via the strong Npy-M bonds. The coordination patterns depend markedly on the anion coordination. In case of the five-coordination system, the distortion parameter ? values were useful to classify their coordination geometries such as trigonal bipyramid or square pyramid. Three dimensional cation binding with the armed macrocycles is one of the important topics not only in the area of the ion transport but also in the construction of new metallo-supramolecules. In partircular, N-pivot armed macrocycles with pyridine-type pendant tend to be able to direct their side arm toward the guest since the hetero N atom is directed toward the metal cation. Sometimes the positions of the hetero N atom (Npy) in the pyridine arms affect the resulting topologies of the metallosupramolecules. Habata et al. reported the interesting bowl-type cyclic dimer and cylic trimer silver(I) complexes from 3'-pyridylmethyl- and 4'-pyridylmethyl-armed monoaza-12-crown-4, respectively

109

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

110

Compound pendant drop tensiometry for interfacial tension measurement at zero bond number.  

Science.gov (United States)

A widely used method to determine the interfacial tension between fluids is to quantify the pendant drop shape that is determined by gravity and interfacial tension forces. Failure of this method for small drops or small fluid density differences is a critical limitation in microfluidic applications and when only small fluid samples are available. By adding a small spherical particle to the interface to apply an axisymmetric deformation, both the particle density and the interfacial tension can be simultaneously and precisely determined, providing an accurate and elegant solution to a long-standing problem. PMID:25494530

Neeson, Michael J; Chan, Derek Y C; Tabor, Rico F

2014-12-30

111

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

Science.gov (United States)

A hitherto unknown mechanism for wetting transition is reported. When a pendant drop settles upon deposition, there is a virtual "collision" where its center of gravity undergoes rapid deceleration. This induces a high water hammer-type pressure that causes wetting transition. A new phase diagram shows that both large and small droplets can transition to wetted states due to the new deceleration driven and the previously known Laplace mechanisms, respectively. It is explained how the attainment of a nonwetted Cassie-Baxter state is more restrictive than previously known. PMID:21405283

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

2011-01-21

112

Some Reconsiderations on Pendant-Legged Buddha Images in the Dv?ravat? Artistic Tradition  

OpenAIRE

The aim of this paper is to reassess some common ideas about a particular type of buddha image frequently found in Central Thailand during the ca. 7th- 8th centuries: the buddhas seated in the so-called "European fashion" or pendant-legged, often labeled pralambap?d?sana in Sanskrit. While briefly dealing with iconographic questions--including the origins and meanings of this particular posture--this paper will also discuss the matter of terminology in relation to the royal symbolism convey...

Revire, Nicolas

2011-01-01

113

Robotic Arm Unwrapped  

Science.gov (United States)

This image, taken shortly after NASA's Phoenix Mars Lander touched down on the surface of Mars, shows the spacecraft's robotic arm in its stowed configuration, with its biobarrier successfully unpeeled. The 'elbow' of the arm can be seen at the top center of the picture, and the biobarrier is the shiny film seen to the left of the arm. The biobarrier is an extra precautionary measure for protecting Mars from contamination with any bacteria from Earth. While the whole spacecraft was decontaminated through cleaning, filters and heat, the robotic arm was given additional protection because it is the only spacecraft part that will directly touch the ice below the surface of Mars. Before the arm was heated, it was sealed in the biobarrier, which is made of a trademarked film called Tedlar that holds up to baking like a turkey-basting bag. This ensures that any new bacterial spores that might have appeared during the final steps before launch and during the journey to Mars will not contact the robotic arm. After Phoenix landed, springs were used to pop back the barrier, giving it room to deploy. The base of the lander's Meteorological Station can be seen in this picture on the upper left. Because only the base of the station is showing, this image tells engineers that the instrument deployed successfully. The image was taken on landing day, May 25, 2008, by the spacecraft's Surface Stereo Imager. 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

114

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

115

PHENIX Muon Arms  

International Nuclear Information System (INIS)

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

116

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

117

Robotic Arm End Effector  

Science.gov (United States)

Image illustrates the tools on the end of the arm that are used to acquire samples, image the contents of the scoop, and perform science experiments. 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

118

An Athletic Arms Race  

Science.gov (United States)

Myles Brand is a person of unquestioned integrity and high principle. As president of the National Collegiate Athletic Association (NCAA), he has been asked to fend off an unruly mob with a switch. In the present environment for collegiate sports, his chances for success are slight, at best. What Brand and the NCAA face today is a very real "arms

Budig, Gene A.

2007-01-01

119

Robotic Arm of Rover 1  

Science.gov (United States)

JPL engineers examine the robotic arm of Mars Exploration Rover 1. The arm is modeled after a human arm, complete with joints, and holds four devices on its end, the Rock Abrasion Tool which can grind into Martian rocks, a microscopic imager, and two spectrometers for elemental and iron-mineral identification.

2003-01-01

120

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 moile 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

121

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

Science.gov (United States)

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 (L(1)) 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 (L(2)) 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 L(1): PVC:1-CN:NaTPB in the ratio of 6: 32: 58: 4 (w/w; mg). The performance of the membrane based on L(1) was compared with polymeric membrane electrode (PME) as well as with coated graphite electrode (CGE). The electrodes exhibit Nernstian slope for Tb(3+) 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 10s and 8s, 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 Tb(3+) ions with EDTA and in determination of fluoride ions in various samples. It can also be used in direct determination of Tb(3+) ions in tap water and various binary mixtures with quantitative results. PMID:19110124

Singh, Ashok K; Singh, Prerna; Banerjee, Shibdas; Mehtab, Sameena

2009-02-01

122

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

Energy Technology Data Exchange (ETDEWEB)

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 (L{sub 1}) 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 (L{sub 2}) 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 L{sub 1}: PVC:1-CN:NaTPB in the ratio of 6: 32: 58: 4 (w/w; mg). The performance of the membrane based on L{sub 1} was compared with polymeric membrane electrode (PME) as well as with coated graphite electrode (CGE). The electrodes exhibit Nernstian slope for Tb{sup 3+} ions with limits of detection of 3.4 x 10{sup -8} mol L{sup -1} for PME and 5.7 x 10{sup -9} mol L{sup -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 Tb{sup 3+} ions with EDTA and in determination of fluoride ions in various samples. It can also be used in direct determination of Tb{sup 3+} ions in tap water and various binary mixtures with quantitative results.

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

2009-02-02

123

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)

124

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

125

Phoenix Robotic Arm Camera  

Science.gov (United States)

The Phoenix Robotic Arm Camera (RAC) is a variable-focus color camera mounted to the Robotic Arm (RA) of the Phoenix Mars Lander. It is designed to acquire both close-up images of the Martian surface and microscopic images (down to a scale of 23 ?m/pixel) of material collected in the RA scoop. The mounting position at the end of the Robotic Arm allows the RAC to be actively positioned for imaging of targets not easily seen by the Stereo Surface Imager (SSI), such as excavated trench walls and targets under the Lander structure. Color information is acquired by illuminating the target with red, green, and blue light-emitting diodes. Digital terrain models (DTM) can be generated from RAC images acquired from different view points. This can provide high-resolution stereo information about fine details of the trench walls. The large stereo baseline possible with the arm can also provide a far-field DTM. The primary science objectives of the RAC are the search for subsurface soil/ice layering at the landing site and the characterization of scoop samples prior to delivery to other instruments on board Phoenix. The RAC shall also provide low-resolution panoramas in support of SSI activities and acquire images of the Lander deck for instrument and Lander check out. The camera design was inherited from the unsuccessful Mars Polar Lander mission (1999) and further developed for the (canceled) Mars Surveyor 2001 Lander (MSL01). Extensive testing and partial recalibration qualified the MSL01 RAC flight model for integration into the Phoenix science payload.

Keller, H. U.; Goetz, W.; Hartwig, H.; Hviid, S. F.; Kramm, R.; Markiewicz, W. J.; Reynolds, R.; Shinohara, C.; Smith, P.; Tanner, R.; Woida, P.; Woida, R.; Bos, B. J.; Lemmon, M. T.

2008-10-01

126

ARM Soc Based Enotebook  

OpenAIRE

In recent years, electronic media has grown very fast replacing papers, tape devices, books, etc. The new technologies provide large number of data into single device, fast searching options and more readability than ever. As eBooks are replacing books; we are proposing ENotebook system in which user can write as he did in notebook, save, searches and then reread content. This paper presents design and development of ENotebook using ARM7. The system uses touch screen to get in...

Bawankar, Pranita C.; Rane, Prof U. A.

2014-01-01

127

Sensitized non-coherent photon upconversion by intramolecular triplet-triplet annihilation in a diphenylanthracene pendant polymer  

Science.gov (United States)

Non-coherent photon upconversion by rapid intramolecular triplet-triplet annihilation has been observed following nanosecond laser excitation of Ru(dmb)3 and sequential two-fold triplet energy sensitization of a polymer containing 30 pendant diphenylanthracene groups. A global kinetic analysis of the system has been performed; the intramolecular annihilation step occurs on a sub-nanosecond time scale.

Tilley, Andrew J.; Robotham, Benjamin E.; Steer, Ronald P.; Ghiggino, Kenneth P.

2015-01-01

128

Effects of wake dynamics on infrared measurements of particle cloud temperatures in the superheater pendant region of utility boilers  

International Nuclear Information System (INIS)

Turbulent particle cloud temperatures in the superheater pendant region are critical in coal-fired utility boilers not only for the interactions between turbulence and radiative heat transfer, but also for the ash deposit slagging and fouling on superheater tubes. The false infrared particle temperature fluctuations due to the pendant wake dynamics may cause large errors in modeling of the radiation transport. This paper presents a model to theoretically analyze the effects of wake dynamics on the false infrared particle cloud temperature fluctuations in the superheater pendant region. The preferred frequency in the power spectra and the root mean square temperature fluctuations are predicted theoretically and the effects of utility boiler operating conditions are analyzed. The preferred frequency is twice the vortex shedding frequency and is proportional to the flue gas velocity, and inversely proportional to the superheater tube diameter. The root mean square temperature fluctuations are proportional to the initial particle volume fraction and inversely proportional to the 1.04 power of the particle mass weighted mean diameter. -- Highlights: ? Superheater pendant wake causes the false infrared particle temperature fluctuations. ? Infrared particle temperatures fluctuate at twice the vortex shedding frequency. ? Root mean square temperature fluctuation is proportional to particle volume fraction. ? The present model predicts using only the utility boiler operating conditions

129

Phoenix Robotic Arm  

Science.gov (United States)

A vital instrument on NASA's Phoenix Mars Lander is the robotic arm, which will dig into the icy soil and bring samples back to the science deck of the spacecraft for analysis. In September 2006 at a Lockheed Martin Space Systems clean room facility near Denver, spacecraft technician Billy Jones inspects the arm during the assembly phase of the mission. Using the robotic arm -- built by the Jet Propulsion Laboratory, Pasadena -- the Phoenix mission will study the history of water and search for complex organic molecules in the ice-rich soil. The Phoenix mission is led by Principal Investigator Peter H. Smith of the University of Arizona, Tucson, with project management at NASA's Jet Propulsion Laboratory and development partnership with Lockheed Martin Space Systems. International contributions for Phoenix are provided by the Canadian Space Agency, the University of Neuchatel (Switzerland), the University of Copenhagen, and the Max Planck Institute in Germany. JPL is a division of the California Institute of Technology in Pasadena.

2007-01-01

130

Reduction of Oxygen Catalyzed by Nickel Diphosphine Complexes with Positioned Pendant Amines  

International Nuclear Information System (INIS)

Nickel(II) bis(diphosphine) complexes that contain positioned bases in the second coordination sphere have been found to catalyze the reduction of O2 with H2 to selectively form water. The complexes also serve as electrocatalysts for the reduction of O2 with the addition of a weak acid. In contrast, a closely related nickel diphosphine complex without the positioned bases is catalytically inactive for O2 reduction. These results indicate that pendant bases in synthetic catalysts for O2 reduction can play a similar role to proton relays in enzymes, and that such relays should be considered in the design of catalysts for multi-electron and multi-proton reactions.

131

Synthesis of chitosan microspheres containing pendant cyclodextrin moieties and their interaction with biological active molecules.  

Science.gov (United States)

A new route to obtain chitosan derivatives containing cyclodextrin moieties as pendant groups was developed. The chitosan microspheres, obtained through crosslinking with glutaraldehyde of an acetic acid solution of chitosan, in an organic suspension medium, were reacted with chloroacyl cyclodextrins in organic basic solvents. The acyl cyclodextrin moieties are linked to the chitosan microspheres through C-N bonds, with the elimination of HCl; higher amounts of acyl cyclodextrin are linked to the microspheres with a smaller crosslinking degree. The chitosan-cyclodextrin conjugates retain higher amounts of bioactive substances (nalidixic acid, piroxicam) or of p-nitrophenol (model substance) than their parent chitosan supports, both by ionic forces and by the formation of inclusion complexes in the cyclodextrin inner cavities. After these preliminary studies, one can appreciate that the cyclodextrin-chitosan conjugates could be used as supports for chromatographic separations or controlled release drug systems. PMID:16305386

Georgeta, Mocanu; Elie, About-Jaudet; Didier, LeCerf; Luc, Picton; Adrian, Carpov; Guy, Muller

2004-07-01

132

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

International Nuclear Information System (INIS)

A new activation method has been developed for initiating electroless metal deposition on silicon substrates without SnCl2 sensitization and roughening condition. Silicon wafers are first coated with thiol-terminated self-assembled monolayers (SAMs), and then catalyzed with a stable tin-free Pd(II)-based colloidal solution. Atomic force microscopy (AFM), Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS) were used to characterize the step-by-step surfaces and study the binding mechanism of Pd(II) with SAMs onto surfaces. Results show that Pd(II) oligomer particles are chemisorbed on pendant thiol surfaces through S-Pd bonds. This process involves fewer steps than the conventional Sn/Pd combined activation one. Furthermore, the chemical bound initiator possesses longevity and can be stored for a long time before metallization

133

Motion driven by the interface. [pendant drop surface tension in microgravity  

Science.gov (United States)

Due to the reduction in buoyant forces aboard orbiting spacecraft such as the Space Shuttle, fluid motion driven by gradients in interfacial tension will be important in the processing of materials in space. In this paper, preliminary results from a study of surface tension driven flow in a pendant drop are reported. The drop is heated from above, and the resulting temperature gradients on the drop surface give rise to interfacial tension gradients. These, in turn, drive a circulation in the drop which is made visible by suitable tracers. The velocities are measured using a video technique, and the data on core velocities are found to agree well with results from a predictive theoretical model.

Jayaraj, K.; Cole, R.; Subramanian, R. S.

1983-01-01

134

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

135

Phoenix Robotic Arm Rasp  

Science.gov (United States)

This photograph shows the rasp protruding from the back of the scoop on NASA's Phoenix Mars Lander's Robotic Arm engineering model in the Payload Interoperability Testbed at the University of Arizona, Tucson. This is the position the rasp will assume when it drills into the Martian soil to acquire an icy soil sample for analysis. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is led by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

2008-01-01

136

Removable molar power arm  

OpenAIRE

Attachment of force elements from the gingival hook of maxillary molar tubes during the retraction of the anterior teeth is very common in orthodontic practice. As the line of force passes below the center of resistance (CR) of molar, it results its mesial tipping and also anchorage loss. To overcome this problem, the line of force should pass along the CR of molar. This article highlights a method to overcome this problem by attaching a removable power arm to the headgear tube of molar tube ...

Verma, Raj Kumar; Jena, Ashok Kumar; Singh, Satinder Pal; Utreja, Ashok Kuamr

2013-01-01

137

Removable molar power arm.  

Science.gov (United States)

Attachment of force elements from the gingival hook of maxillary molar tubes during the retraction of the anterior teeth is very common in orthodontic practice. As the line of force passes below the center of resistance (CR) of molar, it results its mesial tipping and also anchorage loss. To overcome this problem, the line of force should pass along the CR of molar. This article highlights a method to overcome this problem by attaching a removable power arm to the headgear tube of molar tube during the retraction of the anterior teeth. PMID:24124303

Verma, Raj Kumar; Jena, Ashok Kumar; Singh, Satinder Pal; Utreja, Ashok Kuamr

2013-07-01

138

Build Your Own Robot Arm  

Science.gov (United States)

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

IEEE

2012-01-01

139

X-Armed Bandits  

CERN Document Server

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

Bubeck, Sébastien; Stoltz, Gilles; Szepesvari, Csaba

2010-01-01

140

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

141

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

142

Nuclear Arms Race and Environment  

OpenAIRE

This paper introduces a new factor, environment, into nuclear arms race model. In this model, nuclear weapons produce larger defense power compared with conventional arms, but hurt the environment meanwhile. In the global welfare maximum level, both conventional and nuclear weapons budget are zero. However, the competitive equilibrium may not achieve the optimum. I give the condition to jump out of the prisoner's dilemma.

Li, Anpeng

2012-01-01

143

Robotic Arm Biobarrier Cable  

Science.gov (United States)

This image, taken by the Surface Stereo Imager on NASA's Phoenix Mars Lander on the 14th Martian day of the mission (June 7, 2008), shows the cable that held the Robotic Arm's biobarrier in place during flight has snapped. The cable's springs retracted to release the biobarrier right after landing. To the lower right of the image a spring is visible. Extending from that spring is a length of cable that snapped during the biobarrier's release. A second spring separated from the cable when it snapped and has been photographed on the ground under the lander near one of the legs. 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

144

Predicting height from arm measurements.  

Science.gov (United States)

Height measurement is required to standardize measures of physical capacity (e.g., pulmonary function) and to adjust drug dosage in the physically disabled. To estimate height in wheelchair-bound patients, we examined the relation of four different upper extremity measurements to height in 119 normal individuals aged 0.5-56 years. Regression analysis was performed for each of the following: (a) interacromioclavicular distance, (b) upper arm, (c) lower arm (cubit), (d) arm span; with height. Pearson correlation coefficients of 0.937, 0.967, 0.975, and 0.989, respectively, were obtained (accuracy +/- 5%, 90% confidence interval, for upper and lower arm measurements). We conclude that height can be predicted reliably from arm measurements. PMID:8245203

Jarzem, P F; Gledhill, R B

1993-01-01

145

Signature électromagnétique de la dynamique corticale pendant l'éveil et le sommeil chez l'homme  

OpenAIRE

L'analyse de la fonction cérébrale à de multiples échelles est une étape nécessaire pour comprendre ses complexités. Dans ce travail de thèse, nous avons étudié cet aspect aux niveaux microscopiques et macroscopiques en utilisant des enregistrements invasifs et non-invasifs. Nous avons utilisé une série d'outils d'analyse communicationnels et de corrélation pour étudier l'activité cérébrale pendant l'éveil et le sommeil. Dans une première étude, nous avons analyse les enre...

Dehghani, Nima

2012-01-01

146

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

147

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

148

Voice control of a dual-arm telerobot  

Science.gov (United States)

This investigation explores voice control of a dual-arm telerobot. A literature review of voice control, voice technology and work measurements is conducted. This review includes a discussion of important voice technology topics, a survey of commercial voice equipment, and a study of industrial and vocational work measurement techniques. A voice control system is created for two Kraft GRIPS Master-Slave telerobotic manipulators. This system is based upon the concept of distributed computer control using inexpensive PC-AT computers that exchange information according to special communication and command protocols. The voice control system consists of four separate sub-systems; a Camera Sub-system that controls a motorized camera mount, a Teach Pendant Sub-system that emulates two standard Termiflex teach pendants, a Switch Sub-system that controls the Kraft Master switches, and a Voice Sub-system that accepts the operator's vocal commands and broadcasts digitally-recorded messages. The Voice Sub-system utilizes a Votan VPC-2100 recognition board and a TI-Speech synthesis board. The vocal commands are organized into a hierarchical structure based upon the fire-and-forget control scheme. A visual display of the vocal command status is also detailed. In order to measure the effect of the voice control system upon the work performance of the telerobot, a formal experimental plan is described using twenty-four untrained operators divided into a voice group and a control group. Each group performs an experimental taskset using modified peg-in-hole vocational rehabilitation assessment test equipment. The experimental taskset consists of eight separate subtasks that exercise each of the four voice control sub-systems. The times to complete the subtasks are recorded to score each group's work performance. A split-plot ANOVA of the performance scores reveals significant group improvements in both the mean performance and the performance variance for those tasks which involve control of the telerobot and its peripheral systems. No significant group differences are found for those subtasks which chiefly involve the dexterity of the telerobotic Slaves.

Haberlein, Robert Arthur

149

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

KAUST Repository

A novel one-pot methodology combining anionic polymerization and polyhomologation, through a "bridge" molecule (BF3OEt 2), was developed for the synthesis of polyethylene (PE)-based block copolymers. The anionically synthesized macroanion reacts with the "bridge" molecule to afford a 3-arm star (trimacromolecular borane) which serves as an initiator for the polyhomologation. 2013 The Royal Society of Chemistry.

Zhang, H.

2013-08-07

150

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

151

Design of Robotic Arm Control System Mimics Human Arm Motion  

OpenAIRE

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

152

ARM Soc Based Enotebook  

Directory of Open Access Journals (Sweden)

Full Text Available In recent years, electronic media has grown very fast replacing papers, tape devices, books, etc. The new technologies provide large number of data into single device, fast searching options and more readability than ever. As eBooks are replacing books; we are proposing ENotebook system in which user can write as he did in notebook, save, searches and then reread content. This paper presents design and development of ENotebook using ARM7. The system uses touch screen to get input data and operations like save, delete, open & close of data file. All data sensed by touch screen is digitized by internal ADCs of LPC2148 microcontroller which gives low power platform with fast execution. The output is shown on graphical LCD. Whatever user writes on screen it may need to save for future use. The content of such hand written data will be in graphical/pictorial form hence required large of memory for storage. We can provide external memory using pen drive, memory card, EEPROM etc. in this system we are using SD card interfacing through SPI port.

Pranita C Bawankar

2014-05-01

153

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

154

Copper complexes with new oxaaza-pendant-armed macrocyclic ligands: X-ray crystal structure of a macrocyclic copper(II) complex  

OpenAIRE

The synthesis of new oxaaza macrocyclic ligands (2-4) derived from O1,O7-bis(2-formylphenyl)-1,4,7-trioxaheptane and functionalized tris(2-aminoethyl)amine are described. Mononuclear copper(II) complexes were isolated in the reaction of the corresponding macrocyclic ligand and copper(II) perchlorate. The structure of the [Cu(2)](ClO4)2 complex was determined by X-ray diffraction analysis. The copper(II) ion is five-coordinated by all N5 donor atoms, efficiently encapsulated by the amine termi...

Vicente, Manuel; Bastida, Rufina; Maci?as, Alejandro; Valencia, Laura; Geraldes, Carlos F. G. C.; Brondino, Carlos D.

2005-01-01

155

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

156

Molecular modeling of the pendant chain in Nafion{reg_sign}  

Energy Technology Data Exchange (ETDEWEB)

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

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

1998-03-01

157

Dinuclear rhenium complexes as redox-active pendants in a novel electrodeposited polycyclopentadithiophene material.  

Science.gov (United States)

The novel [Re2(?-H)(?-OOC-CPDT)(CO)6(?-3-Me-pydz)] complex (1; OOC-CPDT = 4H-cyclopenta[2,1-b:3,4-b']dithiophene-4-carboxylate, 3-Me-pydz = 3-methylpyridazine) has been prepared and characterized by single-crystal X-ray diffraction, density functional theory (DFT), and time-dependent DFT computations, UV-vis absorption and emission spectroscopy, and cyclic voltammetry (CV). The measured properties indicate the lack of electronic communication in the ground state between the CPDT and the rhenium diazine moieties. Oxidative electropolymerization of 1, achieved by repeated potential cycling (-0.4 to +1.0 V vs Fc(+)/Fc, in acetonitrile) with different supporting electrolytes, on different electrodes, afforded an electroactive and stable metallopolymer (poly-1). In situ measurements of the mass of the growing film (on a gold electrode, with an electrochemical quartz microbalance) confirmed the regularity of the polymerization process. The polymer exhibits two reversible oxidation peaks of the thiophene chain and a broad irreversible reduction peak (-1.4 V, quite close to that observed for the reduction of monomer 1), associated with a remarkably delayed sharp return peak, of comparable associated charge, appearing in close proximity (+0.3 V) to the first oxidation peak of the neutral polythiophene chain. This charge-trapping effect can be observed upon repeated cycles of p and n doping, and the negative charge is maintained even if the charged electrode is removed from the solution for many hours. Electrochemical impedance spectroscopy showed that the main CV oxidation peak corresponds to facile charge transfer, combined with very fast diffusion of both electrons and ions within the polymer. In summary, poly-1 provides a new example of a metallopolymer, in which the conductive properties of the ?-conjugated system are added to the redox behavior of the pendant-isolated complexes. PMID:25285663

Procopio, Elsa Quartapelle; Bonometti, Valentina; Panigati, Monica; Mercandelli, Pierluigi; Mussini, Patrizia R; Benincori, Tiziana; D'Alfonso, Giuseppe; Sannicolò, Francesco

2014-10-20

158

Changing patterns of arms transfers  

International Nuclear Information System (INIS)

Three factors in the international system have been of importance for the trade of arms: the role of the main actors on the supply side and since 1970 on the demand side, the permanently increasing importance of economics, and the balance trade, industrial capacity and jobs in supplier countries and purchasing power of potential importers. Two political events in 1991 had lasting effect on the development of the trade in arms: the dissolution of Soviet Union and the Gulf War

159

Robotic Arm for Remote Surgery  

OpenAIRE

Recent advances in telecommunications have enabled surgeons to operate remotely on patients with the use of robotics. The investigation and testing of remote surgery using a robotic arm is presented. The robotic arm is designed to have four degrees of freedom that track the surgeon's x, y, z positions and the rotation angle of the forearm {\\theta}. The system comprises two main subsystems viz. the detecting and actuating systems. The detection system uses infrared light-emit...

Dinger, Steven; Dickens, John; Pantanowitz, Adam

2013-01-01

160

Zinc, cadmium, and mercury complexes of a pyridyloxy-substituted cyclotriphosphazene: syntheses, structures, and fluxional behavior.  

Science.gov (United States)

The synthesis and characterization of the fluxional, d(10) cyclotriphosphazene complexes, [MLCl(2)] (M = Zn, Cd, and Hg; L = spiro-[(1,1'-biphenyl)-2,2'-dioxy]tetrakis(4-methyl-2-pyridyloxy)cyclotriphosphazene), are described. Single-crystal X-ray structures show that the zinc complex has crystallized into two crystal forms: one as a tetrahedral species, with a N(2)Cl(2) donor set in which a geminal pair of the pendant pyridyloxy nitrogen atoms binds to the zinc, and the other as a trigonal-bipyramidal (tbp) one, with an N(3)Cl(2) donor set. The third nitrogen atom comes from the phosphazene ring and the two pyridyl ligands are non-geminal. The asymmetric unit of the cadmium complex contains three structurally distinct molecules. One molecule has a tbp structure similar to that of the zinc complex. The second molecule has a six-coordinate, distorted octahedral geometry around the cadmium center with a N(4)Cl(2) donor set, with three of the nitrogen donor atoms coming from the pendant pyridyloxy arms. The third site contains a tbp complex and a distorted octahedral species with a relative occupancy of 3:1. The identification of these three different forms in the one crystal suggests that the energy difference between the tbp and distorted octahedral isomers is not large. Quantitative analysis of the (1)H NMR and variable-temperature (31)P NMR spectra of the zinc, cadmium, and mercury complexes in a CD(2)Cl(2) solution, coupled with the X-ray structural results, shows that an associative fluxional mechanism (?S(++) < -65 J mol(-1) K(-1)) is operating. PMID:23025919

Ainscough, Eric W; Brodie, Andrew M; Edwards, Patrick J B; Jameson, Geoffrey B; Otter, Carl A; Kirk, Stephen

2012-10-15

161

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

International Nuclear Information System (INIS)

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

162

Pierre Vidal-Naquet et le combat d'un intellectuel contre la torture pendant la guerre d'Algérie  

OpenAIRE

Min masteroppgave som har tittelen: ?Pierre Vidal-Naquet et le combat d?un intellectuel contre la torture pendant la guerre d?Algérie?, tar for seg den franske intellektuelle historikeren Pierre Vidal-Naquet et og hans engasjement mot bruken av tortur under Algerie krigen 1954-1962. Oppgaven er delt inn i tre deler. I den første delen redegjør jeg for metoden jeg bruker, videre presenterer jeg forhistorien til Algerie krigen og dens utvikling. I del 1 finnes også en generell beskri...

Traaholt, Stine

2006-01-01

163

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

164

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 ‘super armed' glucosyl, mannosyl, rhamnosyl and galactosyl donors, which could cross couple with the armed acceptors phenyl 2,3,4-tri-O-benzyl-ß-D-thioglucoside or phenyl 2,3,6-tri-O-benzyl-ß-D-thioglucoside to give the corresponding armed disaccharides in good to excellent yields.

Bols, Mikael; Pedersen, Christian Marcus

2007-01-01

165

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

166

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...

167

Proterozoic and Lower Cambrian miogeoclinal rocks of Snow Lake pendant, Yosemite-Emigrant Wilderness, Sierra Nevada, California: Evidence for major Early Cretaceous dextral translation  

Science.gov (United States)

Detailed stratigraphic and structural studies at Snow Lake pendant have established new evidence for the presence of uppermost Precambrian and Lower Cambrian miogeoclinal strata within the axial region of the Sierra Nevada batholith. Lithologic and stratigraphic data along with trace fossils, a distinctive Triassic overlap sequence (Fairview Valley Formation?), dikes probably related to the Jurassic Independence dike swarm, and structural history suggest that the older rocks of Snow Lake pendant correlate with the Stirling Quartzite, Wood Canyon Formation, Zabriskie Quartzite, and Carrara Formation in the western Mojave Desert and San Bernardino Mountains. This correlation implies approximately 500 km of dextral transport of the rocks of Snow Lake pendant along the proposed Mojave-Snow Lake fault. Movement on the fault probably took place after 148 Ma, the age of the Independence dike swarm, and prior to 110 Ma, the age of plutons in the central part of the Sierra Nevada batholith.

Lahren, Mary M.; Schweickert, Richard A.

1989-02-01

168

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

169

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

170

Hand/Wrist/Arm Problems  

Science.gov (United States)

... are all signs of INFECTION in the hand, wrist or arm. URGENT See your doctor right away. Use an antibiotic ointment on infected cuts. No 9. Are one or more joints swollen and tender? Yes You may have RHEUMATOID ARTHRITIS, an inflammatory joint condition. You may also have ...

171

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

172

COMPUTER AIDED DESIGN OF MATERIAL HANDLING ARM  

OpenAIRE

Diploma work discusses computer aided design of material handling arm on specific type of material handler. The purpose of this diploma work is to present the methodological approach in developing such an arm. All such arms are made from sheet metal. This work presents some theoretical basics of sheet metal forming and guidelines of designing with sheet metal. At the end, modelling course of handling arm and creation of technical documentation in CATIA V5 software is presented.

Z?itek, Denis

2011-01-01

173

Balancing Loads Among Robotic-Manipulator Arms  

Science.gov (United States)

Paper presents rigorous mathematical approach to control of multiple robot arms simultaneously grasping one object. Mathematical development focuses on relationship between ability to control degrees of freedom of configuration and ability to control forces within grasped object and robot arms. Understanding of relationship leads to practical control schemes distributing load more equitably among all arms while grasping object with proper nondamaging forces.

Kreutz, Kenneth K.; Lokshin, Anatole

1990-01-01

174

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 charensor 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.

175

A controllable synthesis of multi-armed CdTe nanorods  

Science.gov (United States)

A simple, productive and low-cost route has been developed to synthesize multi-armed CdTe nanorods using myristic acid (MA) as a complex agent. The yield of this approach can reach 75%. The dimension of the multi-armed nanorods can be controlled by tuning the molar ratios of Cd/Te and Cd/MA; the diameter can be changed from 2 to 7 nm while the length from 15 to 60 nm. The hexagonal structure was confirmed in x-ray diffraction analysis. However, it was assumed that one crystal is composed of the dominant hexagonal structure along with a cubic structure in the core.

Nie, Wei; He, Jibao; Zhao, Nana; Ji, Xiangling

2006-02-01

176

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.

177

Chemical syntheses and characterizations of II-VI semiconductor nanocrystals  

Science.gov (United States)

This thesis is mainly concerned with the chemical syntheses and property characterizations of a series of II-VI semiconductor nanocrystals. We have synthesized ZnTe and Cr doped ZnTe nanoparticles, ZnSe:en precursor nanoribbon arrays, and CdSe quantum dots (QDs) and tetrapods nanocrystals using simple chemical methods. Structures and compositions of the obtained nanocrystals are characterized by the high-resolution transmission electron microscopy (HRTEM), energy dispersion spectrometry (EDS), X-ray diffraction (XRD), X-ray fluorescence (XRF), and high-resolution scanning electron microscopy (HRSEM). The optical absorption spectroscopy, photoluminescence (PL), and field emission experiments are also carried out. ZnTe and Cr doped ZnTe nanoparticles (ZnTe:Cr) have been synthesized by colloidal nano-synthesis method. The characterizations by XRD, XRF, and TEM show that the synthesized ZnTe and ZnTe:Cr crystals have cubic structure and Cr is incorporated into ZnTe. The magnetic properties of ZnTe:Cr are investigated. A hysteresis is observed in the magnetization versus magnetic field measurements below 10K. The detailed analyses suggest that the hysteresis is possibly originated from the magnetic short-range orders of Zn1-xCrxTe compounds in the sample. Vertically-aligned ZnSe:en precursor nanoribbon arrays have been grown directly on Zn foil via a simple solvothermal procedure. The nanoribbons are 100 ˜ 300 nm in width and several nanometers in thickness. Their lengths are about a few micrometers. The conversion of the ZnSe:en nanoribbon arrays to ZnSe nanoribbon arrays with wurtzite structures is achieved by a thermal annealing in N2 atmosphere. Upon the release of en, the morphology of the ZnSe nanoribbon arrays is well-preserved and the crystallinity of the ribbons is improved. Uniform field emissions were observed from ZnSe nanoribbons. Results show that the ZnSe nanoribbon arrays are good field emitters in comparison with many other nanostructures as having a low turn-on field of 5 V/mum and a high field enhancement factor of 1382. CdSe tetrapod nanocrystals have been synthesized using a simple nano-synthesis method by controlling the protonic acidity of the cadmium OA-TOP precursor. The crystal structure of the tetrapods is determined by HRTEM analysis, which shows that the tetrapod has a zinc blende core and four wurtzite arms. The possible growth mechanism in our experiment is discussed. The electronic structure of tetrapod is calculated in comparison with the spherical dot, indicating that for our tetrapod samples the ground state is dominated by the core diameter and only for the states above the fourth excited state the "arm diameter" effect becomes important. The steady state and transient optical properties of CdSe tetrapods and QDs are studied in details. No qualitative differences are detected. The field emission properties of CdSe tetrapods with different arm lengths are also investigated in details, showing that the longer the arm length, the lower the turn-on field, and the higher the enhancement factor.

Zhao, Lijuan

178

Evidence of Uppermost Proterozoic to Lower Cambrian miogeoclinal rocks and the Mojave-Snow Lake Fault: Snow Lake Pendant, central Sierra Nevada, California  

Science.gov (United States)

Displaced uppermost Precambrian to Lower Cambrian miogeoclinal strata occur within Snow Lake pendant in the central Sierra Nevada. These rocks have been correlated with the Stirling Quartzite, the Wood Canyon Formation, the Zabriskie Quartzite, and the Carrara Formation in the western Mojave Desert and the San Bernardino Mountains (Lahren and Schweickert, 1989; Lahren, 1989). This correlation is based on new, updated, and previously reported data including (1) lithologic similarities, (2) overall stratigraphic sequence, (3) vertical sequence within individual formations, (4) approximate stratigraphic thicknesses, (5) Skolithos in the correct stratigraphie position, (6) depositional environments, and (7) petrographic character and provenance of quartz arenites. The correlation is strengthened by the fact that Snow Lake pendant and the western Mojave share many other close similarities including (1) initial 87Sr/86Sr ratios of associated granitic rocks >0.706, (2) passive margin tectonic setting of Precambrian to Cambrian miogeoclinal rocks, (3) dikes of the Independence dike swarm, (4) possible Lower Triassic overlap sequence, the Fairview Valley Formation, (5) petrographically similar gabbroic complexes of the same age, (6) associated eugeoclinal rocks, and (7) identical(?) pre-Tertiary structural configuration. New U/Pb zircon geochronology unequivocally shows that dikes at Snow Lake pendant are coeval with the Independence dike swarm of the eastern Sierra and the western Mojave desert and that associated gabbroic complexes in both the Mojave and Snow Lake pendant are the same age. Correlation of Snow Lake pendant with the western Mojave requires about 400 km of dextral displacement of the rocks of Snow Lake pendant, together with associated rocks (Snow Lake block), from the western Mojave Desert along the Mojave-Snow Lake fault. Displacement most likely occurred after 150 Ma, the age of the Independence dike swarm, and before about 110 Ma, the age of major plutons within the Sierra Nevada batholith. This interpretation, if correct, holds major implications for allochthonous terranes west of Snow Lake pendant, which were probably attached to the Snow Lake block before its northward transport. In addition, a number of Paleozoic and Mesozoic tectonic features in western Nevada and eastern California may have been offset dextrally along the proposed Mojave-Snow Lake fault.

Lahren, Mary M.; Schweickert, Richard A.; Mattinson, James M.; Walker, J. Douglas

1990-12-01

179

Production of a synthesized plasma  

International Nuclear Information System (INIS)

Neutralization of helium ion beam extracted from a stationarily operated duoplasmatron is studied. It was confirmed that the neutralization of ion space charge occurred mainly at the deceleration stage of the einzel lens, not in the downstream of the neutralizer. The magnetic field and arc current in the duoplasmatron affected substantially the beam divergence. The energy spectrum of the extracted ions was measured with an energy analyzing system consisting of a pre-decelerator and an electrostatic energy analyzer with 900 deflection. The energy spectrum of ions in the synthesized plasma was essentially defined by the operating conditions of the ion source; gas pressure, magnetic field and arc current in the arc discharge. A small difference between the space potential and the potential of the emitter changed the characteristics of the synthesized plasma. (auth.)

180

Catalytic method for synthesizing hydrocarbons  

Science.gov (United States)

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

181

TSS-Thermal Synthesizer System  

Science.gov (United States)

Thermal Synthesizer System (TSS) is integrated set of thermal-analysis application programs designed to solve problems encountered by thermal engineers. Combines functionality of Systems Improved Numerical Differencing Analyzer/Fluid Integrator (SINDA/FLUINT) and radiation analysis with friendly and easily understood user-interface environment coupled with powerful interactive color graphics and geometric modeling capability. Enables thermal engineers to spend more time solving engineering problems instead of laboriously constructing and verifying math models. Written in FORTRAN and C language.

Chimenti, Edward; Rickman, Steven; Vogt, Robert; Longo, Carlos R. Ortiz; Bauman, Noel; Lepore, Joseph; Mackey, Phil; Pavlovsky, James, II; Welch, Mark; Fogerson, Peter; Dawber, Mark; Fong, Cynthia Jone; Hecke, Peter; Morrison, Susan; Castillo, Ernie; Chou, ZU; Fried, Lawrence; Howard, Jerry; Lombardi, Mike; Middleton, Jack

1996-01-01

182

Synthese des Indolalkaloids ?-Cyclopiazonic Acid  

OpenAIRE

The indole alkaloid ?-cyclopiazonic acid (CPA) is one of the few known inhibitors of sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA) besides thapsigargin and artemisinin. Inhibitors of SERCA hold promise as novel anticancer and antimalarial drugs. Since its structure elucidation three racemic syntheses of ?-cyclopiazonic acid have been published. The first part of this dissertation describes the enantioselective and high yielding synthesis of CPA by a modification of the K...

Beyer, Christian

2011-01-01

183

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

184

Impact of Pendant 1, 2, 3-Triazole on the Synthesis and Properties of Thiophene-Based Polymers  

Energy Technology Data Exchange (ETDEWEB)

?-Conjugated moieties are often attached to conjugated polymers to systematically alter their electronic properties. Herein, we report the synthesis and properties of a thiophene polymer bearing a triazole moiety in the third position. Through NMR-based quenching studies, we show that the placement of the triazole moiety alters reaction pathway of the Ni(0)-mediated Grignard metathesis polymerization possibly through chelation. When compared with a triazole on the main chain, the pendant triazole moiety acts as an electron donor and lowers the band gap of the polymer. The triazole moiety also does not hinder the packing of the conjugated backbone. We also show that the fluorescence of this polymer is quenched with PCBM, indicating its potential as a candidate for organic photovoltaic devices.

Nagarjuna, G.; Yurt, Serkan; Jadhav, Kedar G.; Venkataraman, D.

2010-01-01

185

Synthesis, crystal structure, computational and photophysical studies of new hydrazono-thiazole derivatives decorated with N-methyl tetrahydrocarbazole pendant  

Science.gov (United States)

2,3-Dihydro-1H-carbazol-4(9H)-one, obtained from 2,3-Dichloro-5,6-Dicyanobenzoquinone (DDQ) oxidation of tetrahydrocarbazole, on methylation with N, N-dimethylformamide dimethyl acetal (DMF-DMA) furnish N-methyl derivative. The thiosemicarbazone of N-methyl derivative on reaction with 2-bromopropionic acid, ethyl bromopyruvate and dimethyl acetylenedicarboxylate (DMAD) afford hydrazono-thiazolidin-4-one derivatives with tetrahydrocarbazole pendant. X-ray diffraction and DFT studies of (Z)-5-methyl-2-((E)-(9-methyl-2,3-dihydro-1H-carbazol-4(9H)-ylidene)hydrazono)thiazolidin-4-one 5 have been reported. The reaction with dimethyl acetylenedicarboxylate (DMAD) and ethyl bromopyruvate take place without any catalyst and organic solvent. The photophysical properties of these compounds were studied by means of UV/visible absorption spectroscopy and fluorescence spectroscopy.

Gautam, Deepika; Chaudhary, R. P.

2015-01-01

186

HABITAT DE LA TRUITE COMMUNE (SALMO TRUTTA L. PENDANT LA PÉRIODE JUVÉNILE EN RUISSEAU : PRÉFÉRENCES, MOUVEMENTS, VARIATIONS JOURNALIÈRES ET SAISONNIÈRES.  

Directory of Open Access Journals (Sweden)

Full Text Available Cet article synthétise les résultats de travaux récents sur l’habitat de la truite commune pendant sa période juvénile en ruisseau. Par des approches in situ (affluents du Scorff, Bretagne et en milieu expérimental, les variations temporelles d’utilisation de l’habitat ont été étudiées, ainsi que l’influence de certains facteurs abiotiques (vitesse de courant, profondeur, granulométrie, abris et biotiques (prédation, compétition intraspécifique sur les choix d’habitat de l’individu. A l’aide de la bibliographie sur le sujet, nous proposons un bilan des changements journaliers et saisonniers d’habitat du juvénile en ruisseau, depuis l’émergence jusqu’à la première reproduction. En matière de protection des milieux, l’accent est mis sur l’importance de la diversité des habitats disponibles dans les affluents où se reproduit l’espèce.

ROUSSEL J. M.

2002-04-01

187

Synthesis and incorporation of ladder polymer subunits in copolyamides, pendant polymers, and composites for enhanced nonlinear optical response  

Science.gov (United States)

Several electroactive polymers, such as polyacetylene, polythiophene, poly [p-phenylene vinylene] and poly [2,5-thienylene vinylene] have shown promise as NLO-active materials over the past few years. However, as several theoretical and experimental research groups have pointed out in recent publications and symposia, it is not evident that long conjugation lengths are necessary for enhanced (chi) (3) activity. As recently demonstrated, copolyamides which incorporate polyenylic or PTV oligomeric repeat units show (chi) (3)/(alpha) values of ca. 10-13 esu-cm at 532 nm(band-edge). In this paper, the authors discuss how ladder subunits related to the electroactive polymers POL and PTL can be incorporated into polymer films as (a) copolymer repeat units, (b) pendant groups attached to poly [p-hydroxystyrene] and (c) guest-host composites in polycarbonate. Sharp optical absorptions are found in all cases as well as promising (chi) (3) properties.

Spangler, Charles W.; Saindon, Michelle L.; Nickel, Eric G.; Sapochak, Linda S.; Polis, David W.; Dalton, Larry R.; Norwood, Robert A.

1991-09-01

188

Arm locking for space-based laser interferometry gravitational wave observatories  

Science.gov (United States)

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 interspacecraft 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 to study and verify laser frequency noise reduction and suppression techniques under realistic LISA-like conditions. These conditions include the variable Doppler shifts among 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 expected performance in LISA. The presented results are supported by results obtained during experimental studies of arm locking under relevant LISA-like conditions. We measured the noise suppression as well as initial transients and frequency pulling in the presence of Doppler frequency errors. This work has demonstrated the validity and feasibility of arm locking in LISA.

Yu, Yinan; Mitryk, Shawn; Mueller, Guido

2014-09-01

189

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

190

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

191

Magnetic Spiral Arms and Galactic Outflows  

CERN Document Server

Galactic magnetic arms have been observed between the gaseous arms of some spiral galaxies; their origin remains unclear. We suggest that magnetic spiral arms can be naturally generated in the interarm regions because the galactic fountain flow or wind is likely to be weaker there than in the arms. Galactic outflows lead to two countervailing effects: removal of small-scale magnetic helicity, which helps to avert catastrophic quenching of the dynamo, and advection of the large-scale magnetic field, which suppresses dynamo action. For realistic galactic parameters, the net consequence of outflows being stronger in the gaseous arms is higher saturation large-scale field strengths in the interarm regions as compared to in the arms. By incorporating rather realistic models of spiral structure and evolution into our dynamo models, an interlaced pattern of magnetic and gaseous arms can be produced.

Chamandy, Luke; Subramanian, Kandaswamy

2014-01-01

192

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)

193

Control of flexible robotic arms, 1  

International Nuclear Information System (INIS)

Dynamic characteristics and control method of a flexible robotic arm of first degrees of freedom system are shown 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, of 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 type of robotic arms, but also applicable in more general cases. (author)

194

Magnetic spiral arms and galactic outflows  

Science.gov (United States)

Galactic magnetic arms have been observed between the gaseous arms of some spiral galaxies; their origin remains unclear. We suggest that magnetic spiral arms can be naturally generated in the interarm regions because the galactic fountain flow or wind is likely to be weaker there than in the arms. Galactic outflows lead to two countervailing effects: removal of small-scale magnetic helicity, which helps to avert catastrophic quenching of the dynamo, and advection of the large-scale magnetic field, which suppresses dynamo action. For realistic galactic parameters, the net consequence of outflows being stronger in the gaseous arms is higher saturation large-scale field strengths in the interarm regions as compared to in the arms. By incorporating rather realistic models of spiral structure and evolution into our dynamo models, an interlaced pattern of magnetic and gaseous arms can be produced.

Chamandy, Luke; Shukurov, Anvar; Subramanian, Kandaswamy

2015-01-01

195

The DOE ARM Aerial Facility  

Energy Technology Data Exchange (ETDEWEB)

The Department of Energy Atmospheric Radiation Measurement (ARM) Program is a climate research user facility operating stationary ground sites that provide long-term measurements of climate relevant properties, mobile ground- and ship-based facilities to conduct shorter field campaigns (6-12 months), and the ARM Aerial Facility (AAF). The airborne observations acquired by the AAF enhance the surface-based ARM measurements by providing high-resolution in-situ measurements for process understanding, retrieval-algorithm development, and model evaluation that are not possible using ground- or satellite-based techniques. Several ARM aerial efforts were consolidated into the AAF in 2006. With the exception of a small aircraft used for routine measurements of aerosols and carbon cycle gases, AAF at the time had no dedicated aircraft and only a small number of instruments at its disposal. In this "virtual hangar" mode, AAF successfully carried out several missions contracting with organizations and investigators who provided their research aircraft and instrumentation. In 2009, AAF started managing operations of the Battelle-owned Gulfstream I (G-1) large twin-turboprop research aircraft. Furthermore, the American Recovery and Reinvestment Act of 2009 provided funding for the procurement of over twenty new instruments to be used aboard the G-1 and other AAF virtual-hangar aircraft. AAF now executes missions in the virtual- and real-hangar mode producing freely available datasets for studying aerosol, cloud, and radiative processes in the atmosphere. AAF is also engaged in the maturation and testing of newly developed airborne sensors to help foster the next generation of airborne instruments.

Schmid, Beat; Tomlinson, Jason M.; Hubbe, John M.; Comstock, Jennifer M.; Mei, Fan; Chand, Duli; Pekour, Mikhail S.; Kluzek, Celine D.; Andrews, Elisabeth; Biraud, S.; McFarquhar, Greg

2014-05-01

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. 6 references, 3 figures

197

Darwin curves and galaxy arms  

Science.gov (United States)

In the natural world, there exists one kind of structure which is beyond the scope of human laboratorial experiment. It is the structure of galaxies which is usually composed of billions of stars. Spiral galaxies are flat disk-shaped. There are two types of spiral galaxies. The spiral galaxies with some bar-shaped pattern are called barred spirals, and the ones without the pattern are called ordinary spirals. Longer-wavelength galaxy images (infrared, for example) show that ordinary spiral galaxies are basically an axi-symmetric disk that is called exponential disk. For a planar distribution of matter, Jin He defined Darwin curves in the plane as such that the ratio of the matter densities at both sides of the curve is constant along the curve. Therefore, the arms of ordinary spiral galaxies are Darwin curves. Now an important question is that: Are the arms of barred spiral galaxies the Darwin curves too? Fortunately, Jin He designed a piece of Galaxy Anatomy graphic software. With the software, not only can people simulate the stellar density distribution of barred spiral galaxies but also can draw the Darwin curves of the simulated galaxy structure. This paper shows partial evidence that the arms of galaxy NGC 3275, 4548 and 5921 follow Darwin curves.

He, Jin

2014-07-01

198

Manipulating supramolecular self-assembly via tailoring pendant group size of linear vinyl polymers.  

Science.gov (United States)

In a series of poly[di(alkyl) vinylterephthalates] (PDAVTs) synthesized via radical polymerization, fine-tuning the size and shape of the side groups manipulated the supramolecular self-assembly and led to control over the formations between amorphous and 2D ordered hexagonal phases. To introduce the 2D long-range ordered structure, the size of the ester side groups at the 2- and 5-positions of the phenyl rings laterally attached to the backbones had to be in the range of propyl/isopropyl to hexyl. The relatively extended backbones observed in these polymers were attributed to steric effects from the side groups. When the n-alkyl groups were larger than hexyl, the ability to form the liquid crystalline phase gradually decreased. A completely disordered phase could be observed by substituting dodecyl groups as side groups. PMID:12783523

Yin, Xiao-Ying; Ye, Chun; Ma, Xun; Chen, Er-Qiang; Qi, Xiao-Ying; Duan, Xiao-Feng; Wan, Xin-Hua; Cheng, Stephen Z D; Zhou, Qi-Feng

2003-06-11

199

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

200

The performance of arm locking in LISA  

CERN Document Server

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

McKenzie, Kirk; Shaddock, Daniel A

2009-01-01

201

ARM assembly language with hardware experiments  

CERN Document Server

This book provides a hands-on approach to learning ARM assembly language with the use of a TI microcontroller. The book starts with an introduction to computer architecture and then discusses number systems and digital logic. The text covers ARM Assembly Language, ARM Cortex Architecture and its components, and Hardware Experiments using TILM3S1968. Written for those interested in learning embedded programming using an ARM Microcontroller. ·         Introduces number systems and signal transmission methods   ·         Reviews logic gates, registers, multiplexers, decoders and memory   ·         Provides an overview and examples of ARM instruction set   ·         Uses using Keil development tools for writing and debugging ARM assembly language Programs   ·         Hardware experiments using a Mbed NXP LPC1768 microcontroller; including General Purpose Input/Output (GPIO) configuration, real time clock configuration, binary input to 7-segment display, creating ...

Elahi, Ata

2015-01-01

202

Dual arm master controller development  

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. This work was performed as part of the Consolidated Fuel Reprocessing Program at the Oak Ridge National Laboratory. 5 refs., 7 figs., 1 tab

203

The performance of arm locking in LISA  

OpenAIRE

For the laser interferometer space antenna (LISA) to reach it's design sensitivity, the coupling of the free running laser frequency noise to the signal readout must be reduced by more than 14 orders of magnitude. One technique employed to reduce the laser frequency noise will be arm locking, where the laser frequency is locked to the LISA arm length. This paper details an implementation of arm locking, studies orbital effects, the impact of errors in the Doppler knowledge, ...

Mckenzie, Kirk; Spero, Robert E.; Shaddock, Daniel A.

2009-01-01

204

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

205

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

206

Larmor neutron diffraction with one precession arm:  

OpenAIRE

A new variant of Larmor neutron diffraction, applying only a single precession arm in the initial beam, is proposed. The single arm, together with the polarizer and analyser and possible rotators, are mounted in front of the sample. The great advantage with respect to the case with another precession arm in the reflected beam is that magnetic samples can now be investigated, because depolarization and the Larmor phase change of the beam polarization in the sample after the analyser is no long...

Rekveldt, M. T.; Plomp, J.; Well, A. A.

2014-01-01

207

Design Lower Arm Using Optimum Approach  

OpenAIRE

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 s...

Adel Mahmoud Bash

2011-01-01

208

Preventing Interstate Armed Conflict : whose responsibility?  

OpenAIRE

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

209

MODELING AND SIMULATION OF ROBOTIC HUMANOID ARM  

OpenAIRE

In this paper block model and machine model of Robotic humanoid arm has been generated Using MATLAB Simulink. Equations of Kinematics are derived by using D-H notation. By this equation and inverse kinematicsparameters for the motion trajectory have been determined. Kinematic parameters are divided into two groups namely, link parameters and joint parameters. Geometric model and motion of robotic humanoid arm with two link model with 3 Degree of freedom and arm with palm and fingers with 18 d...

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

2012-01-01

210

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

211

Synthesis, properties and controlled release behaviors of hydrogel networks using cyclodextrin as pendant groups.  

Science.gov (United States)

Based on inclusion character of beta-cyclodextrin (beta-CD) with drug molecule and low glass transition temperature of poly(2-hydroxyethyl acrylate) (PHEA), a series of hydrogels with different compositions were synthesized by the copolymerization of a monovinyl cyclodexrin monomer with 2-hydroxyethyl acrylate (HEA). The structure and properties of the hydrogels were characterized by FTIR, DSC, TGA and swelling measurements. It is found that swelling ratios of these beta-CD hydrogels can keep a relative stability in the range of pH from 1.4 to 7.4, and are not sensitive to change in NaCl concentration. Using drug N-acety-5-methoxytryptamine (melatonin, MEL) as a model molecule, the controlled drug release behaviors of these hydrogels were investigated. The results indicate that the diffusion and permeation of MEL from the hydrogels may be a dominant factor for its release. Owing to the formation of MEL/beta-CD retarding diffusion rate of MEL, a sustained release of MEL from hydrogel with high content of beta-CD can be obtained compared with hydrogel PHEA without beta-CD. PMID:15913774

Liu, Yu-Yang; Fan, Xiao-Dong

2005-11-01

212

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 ligands is investigated. ? We have carried out the monoazatetrathia crown ether showed good sensitivity for Cu2+.

213

Molecular Spiral Arms in M31  

Science.gov (United States)

We describe a high-resolution, high-sensitivity CO(1--0) survey of a large fraction of the south-west star-forming "ring" 20 kpc in diameter in M31 made with the 14 m FCRAO telescope and its QUARRY receiver array. At the 45" angular resolution of the telescope, the ring is resolved into giant complexes of molecular gas with typical sizes of a few hundred parsecs and masses in excess to 106 Msolar. Most of these delineate a prominent spiral arm coincident with that traced by atomic hydrogen and dust. This arm appears in all respects quite similar to a prominent spiral arm in our Galaxy at about the same Galactic radius: the Carina arm. Closer to the center, a second fainter molecular spiral arm segment with an H I and dust counterpart is also detected. The main OB associations and the UV light define an arm offset from that traced by the gas by about 500 pc. The H II regions are mainly found either along the edge of the prominent gaseous arm which faces the associations, or aligned with the second fainter gaseous arm. They define Baade's arms S4 and S3, respectively.

Loinard, L.; Dame, T. M.; Koper, E.; Lequeux, J.; Thaddeus, P.; Young, J. S.

1996-10-01

214

MODELING AND SIMULATION OF ROBOTIC HUMANOID ARM  

Directory of Open Access Journals (Sweden)

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

RANJEET RANJAN

2012-06-01

215

Use of snake arm robots  

International Nuclear Information System (INIS)

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

216

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

217

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

218

Crystallization control of molten Ba(B{sub 0.9}Al{sub 0.1}){sub 2}O{sub 4} from supercooled pendant drop  

Energy Technology Data Exchange (ETDEWEB)

Crystallization process of molten Ba(B{sub 0.9}Al{sub 0.1}){sub 2}O{sub 4} from supercooled pendant drop was investigated on a viewpoint of a supercooling and a solid phase formation. Molten pendant drop was crystallized by a rod touching at an crystallization temperature under an adequate degree of supercooling. Three kinds of rods were used. Each rod was made of Pt, hBN and graphite which had different wettability to the molten drop. There were three kinds of phases on a solid Ba(B{sub 0.9}Al{sub 0.1}){sub 2}O{sub 4}, such as a high temperature crystal phase, a low temperature crystal phase and a glass phase. All phases could be formed by the present method. (orig.)

Miyazaki, A.; Kimura, H. [National Research Inst. for Metals, Sakura, Ibaraki (Japan). Tsukuba Lab.

2001-07-01

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  

OpenAIRE

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 par...

Diego Ségalas

2011-01-01

220

Sensory-Feedback Exoskeletal Arm Controller  

Science.gov (United States)

An electromechanical exoskeletal arm apparatus has been designed for use in controlling a remote robotic manipulator arm. The apparatus, called a force-feedback exoskeleton arm master (F-EAM) is comfortable to wear and easy to don and doff. It provides control signals from the wearer s arm to a robot arm or a computer simulator (e.g., a virtual-reality system); it also provides force and torque feedback from sensors on the robot arm or from the computer simulator to the wearer s arm. The F-EAM enables the wearer to make the robot arm gently touch objects and finely manipulate them without exerting excessive forces. The F-EAM features a lightweight design in which the motors and gear heads that generate force and torque feedback are made smaller than they ordinarily would be: this is achieved by driving the motors to power levels greater than would ordinarily be used in order to obtain higher torques, and by providing active liquid cooling of the motors to prevent overheating at the high drive levels. The F-EAM (see figure) includes an assembly that resembles a backpack and is worn like a backpack, plus an exoskeletal arm mechanism. The FEAM has five degrees of freedom (DOFs) that correspond to those of the human arm: 1. The first DOF is that of the side-to-side rotation of the upper arm about the shoulder (rotation about axis 1). The reflected torque for this DOF is provided by motor 1 via drum 1 and a planar four-bar linkage. 2. The second DOF is that of the up-and-down rotation of the arm about the shoulder. The reflected torque for this DOF is provided by motor 2 via drum 2. 3. The third DOF is that of twisting of the upper arm about its longitudinal axis. This DOF is implemented in a cable remote-center mechanism (CRCM). The reflected torque for this DOF is provided by motor 3, which drives the upper-arm cuff and the mechanism below it. A bladder inflatable by gas or liquid is placed between the cuff and the wearer s upper arm to compensate for misalignment between the exoskeletal mechanism and the shoulder. 4. The fourth DOF is that of flexion and extension of the elbow. The reflected torque for this DOF is provided by motor 4 and drum 4, which are mounted on a bracket that can slide longitudinally by a pin-and-slot engagement with the upper-arm cuff to compensate for slight variations in the position of the kinematic center of the elbow. Attached to drum 4 is an adapter plate to which is attached a CRCM for the lower arm. 5. The lower-arm CRCM implements the fifth DOF, which is the twist of the forearm about its longitudinal axis. Motor 5 provides the reflected torque for this DOF by driving the lower-arm cuff. A rod transmits twist and torsion between the lower-arm cuff and the hand cuff. With this system, the motion of the wearer s joints and the reflected torques applied to these joints can be measured and controlled in a relatively simple manner. This is because the anthropomorphic design of the mechanism imitates the kinematics of the human arm, eliminating the need for kinematic conversion of joint-torque and joint-angle data.

An, Bin; Massie, Thomas H.; Vayner, Vladimir

2004-01-01

221

Field, petrologic and detrital zircon study of the Kings sequence and Calaveras complex, Southern Lake Kaweah Roof Pendant, Tulare County, California  

Science.gov (United States)

U-Pb dating of detrital zircon grains separated from elastic sedimentary rocks is combined with field, petrographic and geochemical data to reconstruct the geologic history of Mesozoic rocks exposed at the southern end of the Lake Kaweah metamorphic pendant, western Sierra Nevada. Identification of rocks exposed at Limekiln Hill, Kern County, CA, as belonging to the Calaveras complex and Kings sequence was confirmed. Detrital zircon populations from two Calaveras complex samples provide Permo-Triassic maximum depositional ages (MDA) and reveal a Laurentian provenance indicating that continental accretion of the northwest-trending Kings-Kaweah ophiolite belt was in process prior to the Jurassic Period. Rock types including radiolarian metachert, metachert-argillite, and calc-silicate rocks with marble lenses are interpreted as formed in a hemipelagic environment of siliceous radiolarian deposition, punctuated by extended episodes of lime-mud gravity flows mixing with siliceous ooze forming cafe-silicate protoliths and limestone olistoliths forming marble lenses. Two samples of the overlying Kings sequence turbidites yield detrital zircons with an MDA of 181.4 +/-3.0 Ma and an interpreted provenance similar to other Jurassic metasediments found in the Yokohl Valley, Sequoia and Boyden Cave roof pendants. Age peaks indicative of Jurassic erg heritage are also present. In contrast, detrital zircon samples from the Sequoia and Slate Mountain roof pendants bear age-probability distributions interpreted as characteristic of the Snow Lake block, a tectonic sliver offset from the Paleozoic miogeocline.

Buchen, Christopher T.

222

Cobalt Complexes Containing Pendant Amines in the Second Coordination Sphere as Electrocatalysts for H2 Production  

Energy Technology Data Exchange (ETDEWEB)

A series of heteroleptic 17e- cobalt complexes, [CpCoII(PtBu2NPh2)](BF4), [CpC6F5CoII(PtBu2NPh2)](BF4), [CpC5F4NCoII(PtBu2NPh2)](BF4), [where P2tBuN2Ph = 1,5-diphenyl-3,7-di(tert-butyl)-1,5-diaza-3,7-diphosphacyclooctane, CpC6F5 = C5H4(C6F5), and CpC5F4N = C5H4(C5F4N)] were synthesized, and structures of all three were determined by X-ray crystallography. Electrochemical studies showed that the CoIII/II couple of [CpC5F4NCoII(PtBu2NPh2)]+ appears 250 mV positive of the CoIII/II couple of [CpCoII(PtBu2NPh2)] as a result of the strongly electron-withdrawing perfluorpyridyl substituent on the Cp ring. Reduction of these paramagnetic CoII complexes by KC8 led to the diamagnetic 18e- complexes CpICo(PtBu2NPh2), CpC6F5CoI(PtBu2NPh2), CpC5F4NCoI(PtBu2NPh2), which were also characterized by crystallography. Protonation of these neutral CoI complexes led to the cobalt hydrides [CpCoIII(PtBu2NPh2)H](BF4), [CpC6F5CoIII(PtBu2NPh2)H](BF4), and [CpC5F4NCoIII(PtBu2NPh2)H](BF4). The cobalt hydride with the most electron-withdrawing Cp ligand, [CpC5F4NCoIII(PtBu2NPh2)H]+ is an electrocatalyst for production of H2 using 4-MeOC6H4NH3BF4 (pKaMeCN = 11.86) with a turnover frequency of 350 s-1 and an overpotential of 0.75 V. Experimental measurement of thermochemical data provided further insights into the thermodynamics of H2 elimination. 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. Pacific Northwest National Laboratory is operated by Battelle for the U.S. Department of Energy.

Fang, Ming; Wiedner, Eric S.; Dougherty, William G.; Kassel, W. S.; Liu, Tianbiao L.; DuBois, Daniel L.; Bullock, R. Morris

2014-10-27

223

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

224

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

225

Role of pendant proton relays and proton-coupled electron transfer on the hydrogen evolution reaction by nickel hangman porphyrins  

Science.gov (United States)

The hangman motif provides mechanistic insights into the role of pendant proton relays in governing proton-coupled electron transfer (PCET) involved in the hydrogen evolution reaction (HER). We now show improved HER activity of Ni compared with Co hangman porphyrins. Cyclic voltammogram data and simulations, together with computational studies using density functional theory, implicate a shift in electrokinetic zone between Co and Ni hangman porphyrins due to a change in the PCET mechanism. Unlike the Co hangman porphyrin, the Ni hangman porphyrin does not require reduction to the formally metal(0) species before protonation by weak acids in acetonitrile. We conclude that protonation likely occurs at the Ni(I) state followed by reduction, in a stepwise proton transfer–electron transfer pathway. Spectroelectrochemical and computational studies reveal that upon reduction of the Ni(II) compound, the first electron is transferred to a metal-based orbital, whereas the second electron is transferred to a molecular orbital on the porphyrin ring. PMID:25298534

Bediako, D. Kwabena; Solis, Brian H.; Dogutan, Dilek K.; Roubelakis, Manolis M.; Maher, Andrew G.; Lee, Chang Hoon; Chambers, Matthew B.; Hammes-Schiffer, Sharon; Nocera, Daniel G.

2014-01-01

226

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

227

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.

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

228

Role of pendant proton relays and proton-coupled electron transfer on the hydrogen evolution reaction by nickel hangman porphyrins.  

Science.gov (United States)

The hangman motif provides mechanistic insights into the role of pendant proton relays in governing proton-coupled electron transfer (PCET) involved in the hydrogen evolution reaction (HER). We now show improved HER activity of Ni compared with Co hangman porphyrins. Cyclic voltammogram data and simulations, together with computational studies using density functional theory, implicate a shift in electrokinetic zone between Co and Ni hangman porphyrins due to a change in the PCET mechanism. Unlike the Co hangman porphyrin, the Ni hangman porphyrin does not require reduction to the formally metal(0) species before protonation by weak acids in acetonitrile. We conclude that protonation likely occurs at the Ni(I) state followed by reduction, in a stepwise proton transfer-electron transfer pathway. Spectroelectrochemical and computational studies reveal that upon reduction of the Ni(II) compound, the first electron is transferred to a metal-based orbital, whereas the second electron is transferred to a molecular orbital on the porphyrin ring. PMID:25298534

Bediako, D Kwabena; Solis, Brian H; Dogutan, Dilek K; Roubelakis, Manolis M; Maher, Andrew G; Lee, Chang Hoon; Chambers, Matthew B; Hammes-Schiffer, Sharon; Nocera, Daniel G

2014-10-21

229

Chair rise transfer detection and analysis using a pendant sensor: An algorithm for fall risk assessment in older people.  

Science.gov (United States)

Falls result in substantial disability, morbidity, and mortality among older people. Early detection of fall risks and timely intervention can prevent falls and injuries due to falls. Simple field tests, such as repeated chair rise, are used in clinical assessment of fall risks in older people. Development of on-body sensors introduces potential beneficial alternatives for traditional clinical methods. In this article, we present a pendant sensor based chair rise detection and analysis algorithm for fall risk assessment in older people. The recall and the precision of the transfer detection were 85% and 87% in standard protocol, and 61% and 89% in daily life activities. Estimation errors of chair rise performance indicators: duration, maximum acceleration, peak power and maximum jerk were tested in over 800 transfers. Median estimation error in transfer peak power ranged from 1.9% to 4.6% in various tests. Among all the performance indicators, maximum acceleration had the lowest median estimation error of 0% and duration had the highest median estimation error of 24% over all tests. The developed algorithm might be feasible for continuous fall risk assessment in older people. PMID:25570333

Wei Zhang; Regterschot, G Ruben H; Wahle, Fabian; Geraedts, Hilde; Baldus, Heribert; Zijlstra, Wiebren

2014-08-01

230

75 FR 28185 - Armed Forces Day, 2010  

Science.gov (United States)

...Coast Guard, to plan for appropriate observances each year, with the Secretary of Defense...the United States, to provide for the observance of Armed Forces Day within their jurisdiction...and other organizations to join in the observance of Armed Forces Day each year....

2010-05-20

231

77 FR 30875 - Armed Forces Day, 2012  

Science.gov (United States)

...Coast Guard, to plan for appropriate observances each year, with the Secretary of Defense...the United States, to provide for the observance of Armed Forces Day within their jurisdiction...leaders, and organizations to join in the observance of Armed Forces Day. Finally, I...

2012-05-23

232

76 FR 30497 - Armed Forces Day, 2011  

Science.gov (United States)

...Coast Guard, to plan for appropriate observances, with the Secretary of Defense responsible...the United States, to provide for the observance of Armed Forces Day in an appropriate...and other organizations to join in the observance of Armed Forces Day. Finally, I...

2011-05-25

233

Research in lightweight elastic robotic arms  

Science.gov (United States)

The program involved a series of individual projects coordinated to develop controls for a flexible light weight robot arm. A hydraulically actuated 3-link robot arm was installed on a PRAB hydraulic base, and was designed of tubular steel. A PERT program chart was prepared (appendix B) on which various interrelated project milestones were projected.

Nartker, T. A.

1993-06-01

234

Stress analysis for robot arm version 2  

International Nuclear Information System (INIS)

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

235

Design of a biomimetic robotic octopus arm  

Energy Technology Data Exchange (ETDEWEB)

This paper reports the rationale and design of a robotic arm, as inspired by an octopus arm. The octopus arm shows peculiar features, such as the ability to bend in all directions, to produce fast elongations, and to vary its stiffness. The octopus achieves these unique motor skills, thanks to its peculiar muscular structure, named muscular hydrostat. Different muscles arranged on orthogonal planes generate an antagonistic action on each other in the muscular hydrostat, which does not change its volume during muscle contractions, and allow bending and elongation of the arm and stiffness variation. By drawing inspiration from natural skills of octopus, and by analysing the geometry and mechanics of the muscular structure of its arm, we propose the design of a robot arm consisting of an artificial muscular hydrostat structure, which is completely soft and compliant, but also able to stiffen. In this paper, we discuss the design criteria of the robotic arm and how this design and the special arrangement of its muscular structure may bring the building of a robotic arm into being, by showing the results obtained by mathematical models and prototypical mock-ups.

Laschi, C; Cianchetti, M [Advanced Robotics Technology and Systems Laboratory, Scuola Superiore Sant' Anna, Pisa (Italy); Mazzolai, B; Dario, P [Italian Institute of Technology, Genova (Italy); Mattoli, V [Centre of Research in Microengineering Laboratory, Scuola Superiore Sant' Anna, Pisa (Italy)], E-mail: cecilia.laschi@sssup.it

2009-03-01

236

Design of a biomimetic robotic octopus arm  

International Nuclear Information System (INIS)

This paper reports the rationale and design of a robotic arm, as inspired by an octopus arm. The octopus arm shows peculiar features, such as the ability to bend in all directions, to produce fast elongations, and to vary its stiffness. The octopus achieves these unique motor skills, thanks to its peculiar muscular structure, named muscular hydrostat. Different muscles arranged on orthogonal planes generate an antagonistic action on each other in the muscular hydrostat, which does not change its volume during muscle contractions, and allow bending and elongation of the arm and stiffness variation. By drawing inspiration from natural skills of octopus, and by analysing the geometry and mechanics of the muscular structure of its arm, we propose the design of a robot arm consisting of an artificial muscular hydrostat structure, which is completely soft and compliant, but also able to stiffen. In this paper, we discuss the design criteria of the robotic arm and how this design and the special arrangement of its muscular structure may bring the building of a robotic arm into being, by showing the results obtained by mathematical models and prototypical mock-ups

237

CDE, MBFR, and the arms control process  

International Nuclear Information System (INIS)

This paper reports on the arms control process from 1980 until 1987 which produced no new arms control and has even lost many of the attributes one would normally associate with a process. This was a substantial change from the 1970s, when Western arms control policies sought, with at least some success, to begin reducing by progressive increments the levels of nuclear and non-nuclear armaments while attempting to make war less likely by restructuring the East-West armed confrontation in Europe. After the failure of the SALT II treaty to win ratification in the United States, and given the general impasse in other arms control areas, many analysts suggested that the arms control process had given rise to false expectations that a mutual interest in arms control would help regulate US-Soviet and East-West relations more generally. This charge may in fact be warranted to the extent that public expectations exceeded the realistic ability of the arms control process to change fundamentally the adversarial nature of US-Soviet relations. But the internal goals of the process were relatively modest. Policy usually focused on the do-able rather than on the desirable: an approach that opened the way to possible agreements, but perhaps also invited disappointment with the results and, by implication, with the process itself

238

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

OpenAIRE

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 accele...

K Brahmani, K. S. Roy

2013-01-01

239

Arm locking with Doppler estimation errors  

Energy Technology Data Exchange (ETDEWEB)

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.

Yu Yinan; Wand, Vinzenz; Mitryk, Shawn; Mueller, Guido, E-mail: yinan@phys.ufl.ed [Department of Physics, University of Florida, Gainesville, FL 32611 (United States)

2010-05-01

240

Tetra-armed cyclen bearing two benzo-15-crown-5 ethers in the side arms.  

Science.gov (United States)

A tetra-armed cyclen bearing two benzo-15-crown-5 ethers in the side arms (1) is reported. When 1 equiv of Ag(+) is added to 1, the aromatic side arms cover the Ag(+) incorporated in the cyclen. Upon the addition of more than 1 equiv of Ag(+) to 1, the cyclen moiety binds Ag(+) first, before the crown ether in the side arms subsequently binds Ag(+). The log K11, log K12, and log K13 values for the 1:1, 1:2, and 1:3 (= 1/Ag(+)) complexes were estimated to be 9.4, 5.8, and 4.0, respectively. We found that the tetra-armed cyclen possessing crown ethers in the side arms behaves like an argentivorous molecule even though the crown ether arms bind metal cations. PMID:25248049

Ikeda, Mari; Matsumoto, Mikako; Kuwahara, Shunsuke; Habata, Yoichi

2014-10-01

241

Robotic Arm Comprising Two Bending Segments  

Science.gov (United States)

The figure shows several aspects of an experimental robotic manipulator that includes a housing from which protrudes a tendril- or tentacle-like arm 1 cm thick and 1 m long. The arm consists of two collinear segments, each of which can be bent independently of the other, and the two segments can be bent simultaneously in different planes. The arm can be retracted to a minimum length or extended by any desired amount up to its full length. The arm can also be made to rotate about its own longitudinal axis. Some prior experimental robotic manipulators include single-segment bendable arms. Those arms are thicker and shorter than the present one. The present robotic manipulator serves as a prototype of future manipulators that, by virtue of the slenderness and multiple- bending capability of their arms, are expected to have sufficient dexterity for operation within spaces that would otherwise be inaccessible. Such manipulators could be especially well suited as means of minimally invasive inspection during construction and maintenance activities. Each of the two collinear bending arm segments is further subdivided into a series of collinear extension- and compression-type helical springs joined by threaded links. The extension springs occupy the majority of the length of the arm and engage passively in bending. The compression springs are used for actively controlled bending. Bending is effected by means of pairs of antagonistic tendons in the form of spectra gel spun polymer lines that are attached at specific threaded links and run the entire length of the arm inside the spring helix from the attachment links to motor-driven pulleys inside the housing. Two pairs of tendons, mounted in orthogonal planes that intersect along the longitudinal axis, are used to effect bending of each segment. The tendons for actuating the distal bending segment are in planes offset by an angle of 45 from those of the proximal bending segment: This configuration makes it possible to accommodate all eight tendons at the same diameter along the arm. The threaded links have central bores through which power and video wires can be strung (1) from a charge-coupled-device camera mounted on the tip of the arms (2) back along the interior of the arm into the housing and then (3) from within the housing to an external video monitor.

Mehling, Joshua S.; Difler, Myron A.; Ambrose, Robert O.; Chu, Mars W.; Valvo, Michael C.

2010-01-01

242

Syntheses and Functional Properties of Phthalocyanines  

OpenAIRE

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...

Keiichi Sakamoto; Eiko Ohno-Okumura

2009-01-01

243

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

244

Arm-to-arm variation when evaluating neuromuscular block: an analysis of the precision and the bias and agreement between arms when using mechanomyography or acceleromyography  

DEFF Research Database (Denmark)

Studies comparing acceleromyography and mechanomyography indicate that the two methods cannot be used interchangeably. However, it is uncertain to what extent differences in precision between the methods and the naturally occurring arm-to-arm variation have influenced the results of these studies. Accordingly, the purpose of this study was to examine the precision and the arm-to-arm variation, when the same method is used on both of the arms.

Claudius, C; Skovgaard, L T

2010-01-01

245

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

246

Arms control, nonproliferation, and US national security  

International Nuclear Information System (INIS)

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

247

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

248

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

249

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

250

The arms race between fishers  

Science.gov (United States)

An analysis of the changes in the Dutch demersal fishing fleet since the 1950s revealed that competitive interactions among vessels and gear types within the constraints imposed by biological, economic and fisheries management factors are the dominant processes governing the dynamics of fishing fleets. Double beam trawling, introduced in the early 1960s, proved a successful fishing method to catch deep burying flatfish, in particular sole. In less than 10 years, the otter trawl fleet was replaced by a highly specialised beam trawling fleet, despite an initial doubling of the loss rate of vessels due to stability problems. Engine power, size of the beam trawl, number of tickler chains and fishing speed rapidly increased and fishing activities expanded into previously lightly fished grounds and seasons. Following the ban on flatfish trawling within the 12 nautical mile zone for vessels of more than 300 hp in 1975 and with the restriction of engine power to 2000 hp in 1987, the beam trawl fleet bifurcated. Changes in the fleet capacity were related to the economic results and showed a cyclic pattern with a period of 6-7 years. The arms race between fishers was fuelled by competitive interactions among fishers: while the catchability of the fleet more than doubled in the ten years following the introduction of the beam trawl, a decline in catchability was observed in reference beam trawlers that remained the same. Vessel performance was not only affected by the technological characteristics but also by the number and characteristics of competing vessels.

Rijnsdorp, Adriaan D.; Poos, Jan Jaap; Quirijns, Floor J.; HilleRisLambers, Reinier; De Wilde, Jan W.; Den Heijer, Willem M.

251

Is Negotiated Arms Control Possible?  

Science.gov (United States)

I had a very difficult time deciding on the topic of this talk, since Viki's interests cover such a broad range of activities with which I am also concerned. You can hear next week about the recent exciting work with the SLAC storage rings, a description of the design principles of such rings, and their future promise for new physics through Professor Richter's Loeb Lectures at Harvard. Talking about inelastic lepton scattering during an M.I.T. conference would be bringing coals to Newcastle, since the local M.I.T. physicists are primary agents in these experiments. Broad problems in high energy physics policy, for instance such questions as the relation between University users and the large laboratories, are matters of current concern to Viki and his friends in high energy physics, but I doubt whether many would sit still for a one-hour talk on that subject. I would therefore like to use the opportunity to express some personal views on certain current issues in arms control, since I know that there exists a wide spectrum of involvement and also opinion on this subject in the local community...

Panofsky, W. K. H.

2014-11-01

252

Dermatitis, atopic on the arms (image)  

Science.gov (United States)

This person has inherited allergic skin inflammation (atopic dermatitis) on the arms. Red (erythematous), scaly plaques can be seen on the inside of the elbows (antecubital fossa). In adults, atopic dermatitis ...

253

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

254

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

255

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

256

Generic modular framework for robotic arm applications  

OpenAIRE

Robotic manipulators are becoming a very common tool in modern industries and research laboratories. In order to successfully execute a given task, a control software is necessary that sends and tracks appropriate orders to the robot arm. This paper presents the design principles of a general software framework capable to control any robot arm with any set of sensors. A possible implementation of such a general framework is provided together with experiments on a particular robot platform.

Herna?ndez, Sergi; Mirats-tur, Josep M.

2006-01-01

257

Dual arm manipulation-A survey  

OpenAIRE

Recent advances in both anthropomorphic robots and bimanual industrial manipulators had led to an increased interest in the specific problems pertaining to dual arm manipulation. For the future, we foresee robots performing human-like tasks in both domestic and industrial settings. It is therefore natural to study specifics of dual arm manipulation in humans and methods for using the resulting knowledge in robot control. The related scientific problems range from low-level control to high lev...

Smith, Christian; Karayiannidis, Ioannis; Nalpantidis, Lazaros; Gratal, Javier; Qi, Peng; Dimarogonas, Dimos; Kragic, Danica

2012-01-01

258

The Temporal Structure of Vertical Arm Movements  

OpenAIRE

The present study investigates how the CNS deals with the omnipresent force of gravity during arm motor planning. Previous studies have reported direction-dependent kinematic differences in the vertical plane; notably, acceleration duration was greater during a downward than an upward arm movement. Although the analysis of acceleration and deceleration phases has permitted to explore the integration of gravity force, further investigation is necessary to conclude whether feedforward or feedba...

Gaveau, Je?re?mie; Papaxanthis, Charalambos

2011-01-01

259

Design And Implementation Of Anthropomorphic Robotic Arm  

OpenAIRE

The report focuses on the design and demonstration of an anthropomorphic robotic arm with seven degrees of freedom using readily available low-cost components to perform different real time human hand applications. The robotic arm consists of a shoulder, elbow, wrist and a five-finger gripper. It can perform different gripping actions, such as lateral, spherical, cylindrical and tip-holding gripping actions; each finger has three movable links. The actuator used for the roboti...

Ashish Sharma; Kelvin Lewis

2014-01-01

260

Firm exit and armed conflict in Colombia  

OpenAIRE

This paper uses two unique panel data sets to study the causal effect that armed conflict has over entrepreneurial activity in Colombia. Using a fixed effect estimation methodology at the plant level and controlling for the possible endogeneity of armed conflict through the use of instrumental variables, we find that a one standard deviation in the number of guerrilla and paramilitary attacks in a municipality increases the probability of firm exit in 8.1 percentage points. This effect is str...

Camacho, Andriana; Rodriguez, Catherine

2010-01-01

261

Dynamic analysis of the Schilling Titan 7F robotic arm  

International Nuclear Information System (INIS)

A seven degree of freedom hydraulically actuated robotic arm is modeled using DADS. The low level control system for the arm is included in the model, as is the hydraulic system, and model results are compared with experimental results for the arm. Vane type rotary actuators are used in this arm, and a method for modeling them with DADS elements is presented. 10 figs

262

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).

263

Synthesis, structure, and DNA cleavage properties of copper(II) complexes of 1,4,7-triazacyclononane ligands featuring pairs of guanidine pendants.  

Science.gov (United States)

Two new ligands, L(1) and L(2), have been prepared via N-functionalization of 1,4,7-triazacyclononane (tacn) with pairs of ethyl- or propyl-guanidine pendants, respectively. The X-ray crystal structure of [CuL(1)](ClO4)2 (C1) isolated from basic solution (pH 9) indicates that a secondary amine nitrogen from each guanidine pendants coordinates to the copper(II) center in addition to the nitrogen atoms in the tacn macrocycle, resulting in a five-coordinate complex with intermediate square-pyramidal/trigonal bipyramidal geometry. The guanidines adopt an unusual coordination mode in that their amine nitrogen nearest to the tacn macrocycle binds to the copper(II) center, forming very stable five-membered chelate rings. A spectrophotometric pH titration established the pK(app) for the deprotonation and coordination of each guanidine group to be 3.98 and 5.72, and revealed that [CuL(1)](2+) is the only detectable species present in solution above pH ? 8. The solution speciation of the CuL(2) complex (C2) is more complex, with at least 5 deprotonation steps over the pH range 4-12.5, and mononuclear and binuclear complexes coexisting. Analysis of the spectrophotometric data provided apparent deprotonation constants, and suggests that solutions at pH ? 7.5 contain the maximum proportion of polynuclear complexes. Complex C1 exhibits virtually no cleavage activity toward the model phosphate diesters, bis(p-nitrophenyl)phosphate (BNPP) and 2-hydroxypropyl-p-nitrophenyl phosphate (HPNPP), while C2 exhibits moderate activity. For C2, the respective kobs values measured at pH 7.0 (7.24 (± 0.08) × 10(-5) s(-1) (BNPP at 50 °C) and 3.2 (± 0.3) × 10(-5) s(-1) (HPNPP at 25 °C)) are 40- and 10-times faster than [Cu(tacn)(OH2)2](2+) complex. Both complexes cleave supercoiled pBR 322 plasmid DNA, indicating that the guanidine pendants of [CuL(1)](2+) may have been displaced from the copper coordination sphere to allow for DNA binding and subsequent cleavage. The rate of DNA cleavage by C2 is twice that measured for [Cu(tacn)(OH2)2](2+), suggesting some degree of cooperativity between the copper center and guanidinium pendants in the hydrolysis of the phosphate ester linkages of DNA. A predominantly hydrolytic cleavage mechanism was confirmed through experiments performed either in the presence of various radical scavengers or under anaerobic conditions. PMID:21142006

Tjioe, Linda; Joshi, Tanmaya; Brugger, Joël; Graham, Bim; Spiccia, Leone

2011-01-17

264

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

265

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

266

Synthesis and luminescence properties of lanthanide complexes with a new tripodal ligands featuring salicylamide arms.  

Science.gov (United States)

A series of luminescent lanthanide complexes with a new tripodal ligand featuring salicylamide arms, 2,2',2''-nitrilotris(2-furfurylaminoformylphenoxy)triethylamine (L), were synthesized and characterized by elemental analysis, IR and molar conductivity measurements. Photophysical properties of the complexes were studied by means of UV-vis absorption and steady-state luminescence spectroscopy. Excited-state luminescence lifetimes and quantum yield of the complexes were determined. Luminescence studies demonstrated that the tripodal ligand featuring salicylamide arms exhibits a good antennae effect with respect to the Tb(III) and Dy(III) ion due to efficient intersystem crossing and ligand to metal energy transfer. From a more general perspective, this work offers interesting perspectives for the development of efficient luminescent stains and enlarges the arsenal for developing novel luminescent lanthanide complexes of salicylamide derivatives. PMID:19743523

Song, Xue-Qin; Dong, Wen-Kui; Zhang, Yu-Jie; Liu, Wei-Sheng

2010-01-01

267

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

268

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 enter the field of medical imaging

269

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

270

Direct digital synthesizers : theory, design and applications  

OpenAIRE

Traditional designs of high bandwidth frequency synthesizers employ the use of a phase-locked-loop (PLL). A direct digital synthesizer (DDS) provides many significant advantages over the PLL approaches. Fast settling time, sub-Hertz frequency resolution, continuous-phase switching response and low phase noise are features easily obtainable in the DDS systems. Although the principle of the DDS has been known for many years, the DDS did not play a dominant role in wideband frequency generation ...

Vankka, Jouko

2000-01-01

271

Synthese und kontrollierte radikalische Polymerisation multifunktioneller Monomere  

OpenAIRE

Multifunctional monomers on the basis of acryl- and methacryl derivatives were synthesized and different protective groups were used. After polymerization the protective groups were removed by different methods. Various initiators for the NMP of the monomers were synthesized and the reaction conditions were optimized. The results showed that NMP was not a suitable method for multifunctional acryl- and methacryl derivatives to achieve well-defined homopolymers, although it was successful for c...

Yin, Meizhen

2004-01-01

272

FPGA Implementation of a Parameterized Fourier Synthesizer  

OpenAIRE

Field-Programmable Gate Array (FPGA) offers advantages for many applications, particularly where missions are complex and time performance is critical. For small-production digital acoustic synthesizers, FPGA can achieve the above-mentioned tighter system requirements with low total system costs on single chip. In this manuscript, a real-time acoustic synthesizer is implemented using Fourier series algorithm on Altera's Cyclone II FPGA chip. This work emphasizes systematic designs and paralle...

Yang, Rui; Wang, J. G.; Clement, Benoit; Mansour, Ali

2013-01-01

273

Automatic algebraic computation of basic kinematic equations of tree structure robot arms: application to human arms.  

Science.gov (United States)

Tree structure robot arms have been very little studied due to the complexity of their topological structure compared with those of the simple chain type. This paper presents a symbolic computation of the basic kinematic equations of these tree structure robot arms. This leads to the calculation of the homogeneous transformation matrices (HTMs) of the tree branches. These computations are arranged to need the smallest possible number of arithmetic operations. A computer program MGLAT is developed in Pascal to generate such equations in symbolic form. The human arm which consists of the forearm, a wrist and fingers is a very good example of such a structure. A simplified model of 25 degrees of mobility of such an arm is presented. Its basic kinematic equations need 358 multiplications, 214 additions and 252 equations. These equations are useful for improving the existing designs of the artificial arms for handicapped persons and for designing new robot hands for delicate tasks. PMID:1823787

Megahed, S M

1991-01-01

274

Psychoacoustic Analysis of Synthesized Jet Noise  

Science.gov (United States)

An aircraft noise synthesis capability is being developed so the annoyance caused by proposed aircraft can be assessed during the design stage. To make synthesized signals as realistic as possible, high fidelity simulation is required for source (e.g., engine noise, airframe noise), propagation and receiver effects. This psychoacoustic study tests whether the jet noise component of synthesized aircraft engine noise can be made more realistic using a low frequency oscillator (LFO) technique to simulate fluctuations in level observed in recordings. Jet noise predictions are commonly made in the frequency domain based on models of time-averaged empirical data. The synthesis process involves conversion of the frequency domain prediction into an audible pressure time history. However, because the predictions are time-invariant, the synthesized sound lacks fluctuations observed in recordings. Such fluctuations are hypothesized to be perceptually important. To introduce time-varying characteristics into jet noise synthesis, a method has been developed that modulates measured or predicted 1/3-octave band levels with a (noise recordings. For the aft emission angle, results indicate that signals synthesized using a generic LFO are perceived as more similar to recordings than those using no LFO, and signals synthesized with an angle-specific LFO are more similar to recordings than those synthesized with a generic LFO.

Okcu, Selen; Rathsam, Jonathan; Rizzi, Stephen A.

2013-01-01

275

Stereo matching image processing by synthesized color and the characteristic area by the synthesized color  

Science.gov (United States)

We have developed the stereo matching image processing by synthesized color and the corresponding area by the synthesized color for ranging the object and image recognition. The typical images from a pair of the stereo imagers may have some image disagreement each other due to the size change, missed place, appearance change and deformation of characteristic area. We constructed the synthesized color and corresponding color area with the same synthesized color to make the distinct stereo matching. We constructed the synthesized color and corresponding color area with the same synthesized color by the 3 steps. The first step is making binary edge image by differentiating the focused image from each imager and verifying that differentiated image has normal density of frequency distribution to find the threshold level of binary procedure. We used Daubechies wavelet transformation for the procedures of differentiating in this study. The second step is deriving the synthesized color by averaging color brightness between binary edge points with respect to horizontal direction and vertical direction alternatively. The averaging color procedure was done many times until the fluctuation of averaged color become negligible with respect to 256 levels in brightness. The third step is extracting area with same synthesized color by collecting the pixel of same synthesized color and grouping these pixel points by 4 directional connectivity relations. The matching areas for the stereo matching are determined by using synthesized color areas. The matching point is the center of gravity of each synthesized color area. The parallax between a pair of images is derived by the center of gravity of synthesized color area easily. The experiment of this stereo matching was done for the object of the soccer ball toy. From this experiment we showed that stereo matching by the synthesized color technique are simple and effective.

Akiyama, Akira; Mutoh, Eiichiro; Kumagai, Hideo

2014-09-01

276

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

277

Stellar Motion around Spiral Arms: Gaia Mock Data  

CERN Document Server

We compare the stellar motion around a spiral arm created in two different scenarios, transient/co-rotating spiral arms and density-wave-like spiral arms. We generate Gaia mock data from snapshots of the simulations following these two scenarios using our stellar population code, SNAPDRAGONS, which takes into account dust extinction and the expected Gaia errors. We compare the observed rotation velocity around a spiral arm similar in position to the Perseus arm, and find that there is a clear difference in the velocity features around the spiral arm between the co-rotating spiral arm and the density-wave-like spiral arm. Our result demonstrates that the volume and accuracy of the Gaia data are sufficient to clearly distinguish these two scenarios of the spiral arms.

Kawata, D; Grand, R J J; Siebert, A; Pasetto, S; Cropper, M

2015-01-01

278

Fractures of the humerus during arm wrestling  

Directory of Open Access Journals (Sweden)

Full Text Available Background/Aim. Humeral shaft fractures may occur as a result of arm wrestling. The aim of this study was to present our treatment of humerus fracture sustained during arm wrestling. Methods. A total of six patients, aged 22 to 48, were treated at our department form January 2008 to January 2010 with open reduction and internal fixation and with hanging arm casts. A review of all the relevant literature on the subject was also presented. Results. In all the cases, the fractures healed and function returned to normal. No patient had any neural or vascular compromise. Conclusion. Closed and operative treatments were equally successful in all reported cases. [Projekat Ministarstva nauke Republike Srbije, br. 175-095

Bumbaširevi? Marko Ž.

2014-01-01

279

Working End of Robotic Arm on Phoenix  

Science.gov (United States)

[figure removed for brevity, see original site] Annotated Version This illustration shows some of the components on and near the end of the robotic arm on NASA's Phoenix Mars Lander. Primary and secondary blades on the scoop will aid in the collection of soil samples. A powered rasp will allow the arm to sample an icy layer expected to be about as hard as concrete. The thermal and electrical conductivity probe, which is one part of the Microscopy, Electrochemistry and Conductivity Analyzer, will assess how heat and electrons move through the soil from one spike to another of a four-spike electronic fork that will be pushed into the soil at different stages of digging by the arm.

2007-01-01

280

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

281

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

282

Context-Dependent Arm Pointing Adaptation  

Science.gov (United States)

We sought to determine the effectiveness of head posture as a contextual cue to facilitate adaptive transitions in manual control during visuomotor distortions. Subjects performed arm pointing movements by drawing on a digitizing tablet, with targets and movement trajectories displayed in real time on a computer monitor. Adaptation was induced by presenting the trajectories in an altered gain format on the monitor. The subjects were shown visual displays of their movements that corresponded to either 0.5 or 1.5 scaling of the movements made. Subjects were assigned to three groups: the head orientation group tilted the head towards the right shoulder when drawing under a 0.5 gain of display and towards the left shoulder when drawing under a 1.5 gain of display, the target orientation group had the home & target positions rotated counterclockwise when drawing under the 0.5 gain and clockwise for the 1.5 gain, the arm posture group changed the elbow angle of the arm they were not drawing with from full flexion to full extension with 0.5 and 1.5 gain display changes. To determine if contextual cues were associated with display alternations, the gain changes were returned to the standard (1.0) display. Aftereffects were assessed to determine the efficacy of the head orientation contextual cue. . compared to the two control cues. The head orientation cue was effectively associated with the multiple gains. The target orientation cue also demonstrated some effectiveness while the.arm posture cue did not. The results demonstrate that contextual cues can be used to switch between multiple adaptive states. These data provide support for the idea that static head orientation information is a crucial component to the arm adaptation process. These data further define the functional linkage between head posture and arm pointing movements.

Seidler, R. D.; Bloomberg, J. J.; Stelmach, G. E.

2000-01-01

283

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

284

Humanoid Robot Arm Adaptive Control: Experimental Implementation  

OpenAIRE

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. The...

Khan, Said G.; Mubarak Al Grafi

2014-01-01

285

Phoenix Deploying its Robotic Arm Elbow  

Science.gov (United States)

This animated gif is compiled of images from Phoenix's Stereo Surface Imager (SSI) taken on Sol 3. It shows the stair-step motion used to unstow the arm from a protective covering called the biobarrier. The last two moves allow the arm to stand straight up. 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

286

Testing the Robotic Arm Rasp on Earth  

Science.gov (United States)

Members of NASA Phoenix Mars Mission's Robotic Arm engineering team test the arm's motorized rasp in the Payload Interoperability Testbed at the University of Arizona, Tucson. The testbed has a near-duplicate of the Phoenix lander for use in developing techniques to be used on Mars and for checking commands planned for the lander. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is led by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

2008-01-01

287

Martian Soil Inside Phoenix's Robotic Arm Scoop  

Science.gov (United States)

This image from NASA's Phoenix Mars Lander's Robotic Arm Camera (RAC) shows material from the Martian surface captured by the Robotic Arm (RA) scoop during its first test dig and dump on the seventh Martian day of the mission, or Sol 7 (June 1, 2008). The test sample shown was taken from the digging area informally known as 'Knave of Hearts.' 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

288

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

289

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

290

The development of multipurpose fluorination synthesizer  

Energy Technology Data Exchange (ETDEWEB)

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 [{sup 18}F]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.

Yang, Seung Dae; Kim, Sang Wook; Hur, Min Goo (and others)

2009-02-15

291

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

292

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

293

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

294

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).

Ritsche, MT

2011-03-08

295

Whole arm obstacle avoidance for teleoperated robots  

Energy Technology Data Exchange (ETDEWEB)

This paper describes a collision avoidance system using Whole Arm Proximity (WHAP) sensors on a PUMA 560 robot arm. The capacitance-based sensors generate electric fields which can completely encompass the robot arm and detect obstacles as they approach from any direction. The directional obstacle information gathered by the WHAP sensors together with the sensor geometry and robot configuration is used to scale the commanded joint velocities of the robot. A linearized relationship between the WHAP sensor reading and the distance from the obstacle allows direct transformation of perturbations in VHAP readings to perturbations in joint velocities. The VHAP reading is used to directly reduce the component of the command input velocity along the normal axis of the sensor, allowing graceful reductions in speed as the arm approaches the obstacle. By scaling only the component of the velocity vector in the,direction of the nearest obstacles, the control system restricts motion in the direction of obstacles while permitting unconstrained motion in other directions.

Feddema, J.T.; Novak, J.L.

1993-10-01

296

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

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

STRUCTURED MOLECULAR GAS REVEALS GALACTIC SPIRAL ARMS  

International Nuclear Information System (INIS)

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 13CO 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.

299

Structured Molecular Gas Reveals Galactic Spiral Arms  

Science.gov (United States)

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 13CO 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; Hasegawa, Tetsuo; Koda, Jin

2012-11-01

300

Case Report: Macrocystic Lymphangioma of the Arm  

International Nuclear Information System (INIS)

We report the case of a macrocystic lymphatic malformation present since birth in the right arm of a 3-year-old child. Ultrasound and MRI were consistent with a macrocystic lymphatic malformation, and histology after total resection confirmed the diagnosis. These lesions are common in the head and neck, but rarely occur in the extremities.

301

[A man with a raised upper arm].  

Science.gov (United States)

A 43-year-old man presented at our emergency department with a painful shoulder after a fall with his arm in abduction. Clinical presentation was typical for a luxatio erecta without evidence for neurovasculair damage. It is a rare but important diagnosis because of the high risk of plexus injury. PMID:25563783

van Roosmalen, J; van der Linden, Y; Bod-Jaspers, J

2015-01-01

302

The lure of disarmament and arms reduction  

International Nuclear Information System (INIS)

Nuclear disarmament and arms reduction do not have the same aims. Confusing their definitions means misunderstanding the logic which currently drives the power calculations of yesterday's Great Powers, and their associated approaches to the new strategic actor: China. The author knows the subject well from personal experience. (author)

303

Octopus Uses Two Arms to "Walk Away" from Trouble  

Science.gov (United States)

... br/>Press Release 05-047Octopus Uses Two Arms to "Walk Away" from Trouble First proof of underwater ... certain octopus species use two of their eight arms to walk. Credit and Larger Version March 24 ...

304

A Robotic arm for optical and gamma radwaste inspection  

Science.gov (United States)

We propose Radibot, a simple and cheap robotic arm for remote inspection, which interacts with the radwaste environment by means of a scintillation gamma detector and a video camera representing its light (arm by means of a standard videogame joypad.

Russo, L.; Cosentino, L.; Pappalardo, A.; Piscopo, M.; Scirè, C.; Scirè, S.; Vecchio, G.; Muscato, G.; Finocchiaro, P.

2014-12-01

305

Kinematic decomposition and classification of octopus arm movements  

OpenAIRE

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...

IdoZelman; ShlomiHanassy

2013-01-01

306

Iterative Learning Control of a Flexible Robot Arm Using Accelerometers  

OpenAIRE

Iterative learning control (ILC) is applied to a laboratory scale robot arm with joint flexibility. The ILC algorithm is based on an estimate of the arm angle, where the estimate is formed using measurements of the motor angle and the arm angular acceleration. The design of the ILC algorithm is based on a model obtained from system identification. The ILC algorithm is evaluated experimentally on the robot arm with good results.

Gunnarsson, Svante; Norrlo?f, Mikael; Rahic, Enes; O?zbek, Markus

2003-01-01

307

DYNAMICS OF NON-STEADY SPIRAL ARMS IN DISK GALAXIES  

Energy Technology Data Exchange (ETDEWEB)

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 originates in the continual repetition of this nonlinear 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 corotation point. Due to interaction with their host arms, the energy and angular momentum of the stars change, thereby causing radial migration of the stars. During this process, the kinetic energy of random motion (random energy) of the stars does not significantly increase, and the disk remains dynamically cold. Owing to this low degree of disk heating, short-lived spiral arms can recurrently develop over many rotational periods. The resultant structure of the spiral arms in the N-body simulations is consistent with the observational nature of spiral galaxies. We conclude that the formation and structure of spiral arms in isolated disk galaxies can be reasonably understood by nonlinear interactions between a spiral arm and its constituent stars.

Baba, Junichi; Saitoh, Takayuki R. [Interactive Research Center of Science, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro, Tokyo 152-8551 (Japan); Wada, Keiichi, E-mail: babajn@geo.titech.ac.jp [Graduate School of Science and Engineering, Kagoshima University, 1-21-30 Korimoto, Kagoshima, Kagoshima 890-8580 (Japan)

2013-01-20

308

User and clinician perspectives on DEKA Arm: Results of VA study to optimize DEKA Arm  

OpenAIRE

This article summarizes feedback from Department of Veterans Affairs (VA) subjects and clinicians gathered during the VA optimization study of the DEKA Arm. VA subjects and clinicians tested two DEKA Arm prototypes (second-generation [gen 2] and third-generation [gen 3]). Features of the prototypes in three configurations are described. DEKA used feedback from the VA optimization study and from their own subjects to refine the gen 2 prototype. Thirty-three unique subjects participated in the ...

Linda Resnik, Pt; Shana Lieberman Klinger, Ma; Katherine Etter, Ms

2014-01-01

309

Association between intramuscular fat in the arm following arm training and INSIG2.  

Science.gov (United States)

Insulin-induced gene 2 (INSIG2) single-nucleotide polymorphism (SNP rs7566605) is linked to lipid metabolism, and this study assessed its potential influence on fat in the upper arm following arm training. Twenty healthy sedentary volunteers (22.0?±?1.1 years, body mass index 25.4?±?4.0?kg/m(2) ; mean?±?standard deviation) carried out a 12-week two-arm elbow extensor training (10 maximal extensions with 1?min recovery between bouts) five times per day, five times per week. For 17 volunteers, upper arm muscle and adipose tissue [subcutaneous (SCAT) and intramuscular (IMAT)] volumes were evaluated by magnetic resonance imaging before, immediately after, and 12 months after training and variables were related to the subjects' INSIG2 SNP rs7566605 genotype. Muscle volume and SCAT for the upper arm, as the decrease in IMAT during training were not related to INSIG2 SNP rs7566605: GG: %IMAT 1.0?±?0.9%; GC/CC: %IMAT 0.6?±?0.5% (P?>?0.05). However, in the year following the training, accumulation of upper arm IMAT was twice as large in participants homozygous for the G allele (GG: ?%IMAT +2.5?±?0.8%; GC/CC: ?%IMAT +1.1?±?0.7%; P?

Popadic Gacesa, J Z; Secher, N H; Momcilovic, M; Grujic, N G

2014-12-01

310

Structural Variation of Molecular Gas in the Sagittarius Arm and Inter-Arm Regions  

CERN Document Server

We have carried out survey observations toward the Galactic plane at l~38 deg in the 12CO and 13CO J=1-0 lines using the Nobeyama Radio Observatory 45-m telescope. A wide area (0.8 x 0.8 deg) was mapped with high spatial resolution (17"). The line of sight samples the gas in both the Sagittarius arm and the inter-arm regions. The present observations reveal how the structure and physical conditions vary across a spiral arm. We classify the molecular gas in the line of sight into two distinct components based on its appearance: the bright and compact B component and the fainter and diffuse (i.e., more extended) D component. The B component is predominantly seen at the spiral arm velocities, while the D component dominates at the inter-arm velocities and is also found at the spiral arm velocities. We introduce the brightness distribution function and the brightness distribution index (BDI, which indicates the dominance of the B component) in order to quantify the map's appearance. The radial velocities of BDI p...

Sawada, Tsuyoshi; Sugimoto, Masahiro; Koda, Jin; Handa, Toshihiro

2012-01-01

311

Highly Efficient Syntheses of Hyaluronic Acid Oligosaccharides  

OpenAIRE

Highly efficient syntheses of hyaluronic acid oligosaccharides have been accomplished through the pre-activation based iterative one-pot strategy. A series of oligosaccharides ranging from di- to hexasaccharides were rapidly assembled using only near stoichiometric amounts of the building blocks without aglycon adjustment or purifications of intermediate oligosaccharides. Deprote...

Huang, Lijun; Huang, Xuefei

2007-01-01

312

76 FR 42119 - 36(b)(1) Arms Sales Notification  

Science.gov (United States)

...36(b)(1) Arms Sales Notification...Cooperation Agency. ACTION: Notice...36(b)(1) arms sales notification...transmissions, 120mm test cartridges, spare...special tool and test equipment, personnel...1) of the Arms Export Control...form the basis of research to develop...

2011-07-18

313

Position And Force Control For Multiple-Arm Robots  

Science.gov (United States)

Number of arms increased without introducing undue complexity. Strategy and computer architecture developed for simultaneous control of positions of number of robot arms manipulating same object and of forces and torques that arms exert on object. Scheme enables coordinated manipulation of object, causing it to move along assigned trajectory and be subjected to assigned internal forces and torques.

Hayati, Samad A.

1988-01-01

314

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

315

Sorption and thermodynamic of cation-basic center interactions of inorganic-organic hybrids synthesized from RUB-18  

International Nuclear Information System (INIS)

Synthesized nanostructured hybrids from RUB-18 layered silicate, containing one (N) or three (3N) basic nitrogen atoms attached to pendant chains were applied for copper, nickel and cobalt sorptions. The isotherms obtained from batchwise processes were adjusted to the Freundlich and the Langmuir-Freundlich models for heterogeneous systems. The basic nitrogen centers/acidic cation interactions were followed by calorimetry under batchwise conditions and the results were analyzed by a modified Langmuir equation. The exothermic enthalpic values of -2.50 ± 0.30, -1.62 ± 0.10 and -1.35 ± 0.20 and -15.61 ± 0.20, -8.05 ± 0.14 and -20.48 ± 0.15 kJ mol-1, obtained for Cu2+, Ni2+ and Co2+ titrations with C-RUB-xN (x = 1, 3) materials, suggest a favorable process at the solid/liquid interface for inorganic/organic hybrid cation sorptions. These thermodynamic data, expressed also by reaction spontaneity, infer the use of such hybrids for cation removal from aqueous solution.

316

Sorption and thermodynamic of cation-basic center interactions of inorganic-organic hybrids synthesized from RUB-18  

Energy Technology Data Exchange (ETDEWEB)

Synthesized nanostructured hybrids from RUB-18 layered silicate, containing one (N) or three (3N) basic nitrogen atoms attached to pendant chains were applied for copper, nickel and cobalt sorptions. The isotherms obtained from batchwise processes were adjusted to the Freundlich and the Langmuir-Freundlich models for heterogeneous systems. The basic nitrogen centers/acidic cation interactions were followed by calorimetry under batchwise conditions and the results were analyzed by a modified Langmuir equation. The exothermic enthalpic values of -2.50 {+-} 0.30, -1.62 {+-} 0.10 and -1.35 {+-} 0.20 and -15.61 {+-} 0.20, -8.05 {+-} 0.14 and -20.48 {+-} 0.15 kJ mol{sup -1}, obtained for Cu{sup 2+}, Ni{sup 2+} and Co{sup 2+} titrations with C-RUB-xN (x = 1, 3) materials, suggest a favorable process at the solid/liquid interface for inorganic/organic hybrid cation sorptions. These thermodynamic data, expressed also by reaction spontaneity, infer the use of such hybrids for cation removal from aqueous solution.

Macedo, T.R. [Institute of Chemistry, University of Campinas, UNICAMP, P.O. Box 6154, 13084-971 Campinas, Sao Paulo (Brazil); Petrucelli, G.C. [Institute of Chemistry, Federal University of Goias, UFG, P.O. Box 03, 75805-190 Jatai, Goias (Brazil); Airoldi, C., E-mail: airoldi@iqm.unicamp.br [Institute of Chemistry, University of Campinas, UNICAMP, P.O. Box 6154, 13084-971 Campinas, Sao Paulo (Brazil)

2010-04-20

317

Two new helical compounds based on Keggin clusters and N-donor multidentate ligand: Syntheses, structures and properties  

Science.gov (United States)

Two isostructural polyoxometalate-based inorganic-organic hybrids with 1D helical chain, [CuH3L2(GeMo12O40)]·2H2O (1) and [CuH3L2(SiMo12O40)]·2H2O (2), where L=2,4,5-tri(4-pyridyl)-imidazole have been synthesized under hydrothermal conditions. It is the first time to use the L ligand to synthesis the Keggin-type polyoxometalate-based inorganic-organic hybrids. The two compounds possess the left- and right-handed helical chains and the POMs as pendants attach in the helical chains through Cu-O bonds. The two compounds have been characterized by elemental analyses, infrared (IR) spectroscopy, powder X-ray diffraction (PXRD), X-ray photoelectron spectra (XPS), thermogravimetric analysis (TGA) and photoluminescent spectroscopy. Moreover, nitrogen adsorption-desorption measurement, electrochemical and photocatalysis properties for degradation of methylene blue (MB) upon a UV irradiation of compound 1 have been examined.

Zhou, Shi; Liu, Bo; Li, Xiao-Min; Shi, Tian; Chen, Ya-Guang

2014-11-01

318

A Global Obstacle-avoidance Map for Anthropomorphic Arms  

Directory of Open Access Journals (Sweden)

Full Text Available More and more humanoid robots are used in human society, and they face a wide variety of complicated manipulation tasks, which are mainly to be achieved by their anthropomorphic arms. Obstacle avoidance for the anthropomorphic arm must be a fundamental consideration to guarantee the successful implementation of these tasks. Different from traditional methods searching for feasible or optimal collision-free solutions for the anthropomorphic arm, a global obstacle- avoidance map for the whole arm is proposed to indicate the complete set of feasible solutions. In this map, the motion of the arm can be appropriately planned to intuitively control the configuration of the arm in motion. First, the cubic spline function is adopted to interpolate some well-chosen path points to generate a smooth collision-free path for the wrist of the anthropomorphic arm. Second, based on the path function of the wrist, the time and the self-rotation angle of the arm about the “shoulder-wrist” axis are used to parameterize all possible configurations of the arm so that a global two- dimensional map considering the obstacle avoidance can be established. Subsequently, a collision-free self-rotation angle profile of the arm can be well planned. Finally, the joint trajectories of a specific anthropomorphic arm, which correspond to the planned path of the wrist and self-rotation angle profile of the arm, can be solved on the basis of the general kinematic analysis of the anthropomorphic arm, and the specific structure. Several simulations are conducted to verify that the proposed collision-free motion planning method for anthropomorphic arms has some advantages and can be regarded as a convenient and intuitive tool to control the configuration of the anthropomorphic arm in motion, without collision with obstacles in its surroundings.

Cheng Fang

2014-07-01

319

Diaminoalkane as Spacer Arm between Polystyrene and ?- Cylodextrin in Affinity Chromatography for ?-Amylase Separation  

Directory of Open Access Journals (Sweden)

Full Text Available Stationary phase design in affinity chromatography has to fulfill at least two requirements: non-specific interaction between solid support and or spacer arm and protein target or others is minimal and specific interaction between ligand and protein target is maximal. In this study, stationary phases that consist of polystyrene (PS as solid support, diaminoalkane as spacer arm and with and without ?CD as a ligand are performed in ?-amylase separation. Therefore, the research was carried out in two steps; stationary phase preparation and adsorption parameter determination towards ?-amylase. Stationary phases that consist of PS, 1,6-diaminohexane and ?CD (PS–DAH–?CD and without ?CD (PS–DAH were synthesized. Stationary phase structure was confirmed by FTIR, 13C NMR solid, 13C dan 1H NMR liquid spectroscopy. Other stationary phases, PS–DAP–?CD and PS–DAP that consist of 1,2-diaminopropane (DAP as spacer arm was synthesized in the previous research. Dynamic ?-amylase adsorption isotherm on PS–DAP and PS–DAH shows that both of them did not fix any adsorption isotherm model. The average binding capacity are 0.071 and 0.31 mg/0.1 g resin, respectively. In another hand, PS–DAP–?CD and PS–DAH–?CD fix isotherm adsorption Langmuir model and the adsorption parameters; the maximum binding capacity (qm are 5.5 and 2.1 mg/0.1 g resin, adsorption equilibrium constant (KA are 0.01965 and 0.01925 ?L—1 and desorption rate constant (k2 are 0.201 and 0.774 mg s—1 , respectively. Due to adsorption parameters, PS–DAP–?CD offer the best adsorption capacity and selectivity as stationary phase in affinity chromatography for ?-amylase separation.

Sri Widarti* ,

2014-02-01

320

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.

321

Design of Embedded FMS on ARM9  

Directory of Open Access Journals (Sweden)

Full Text Available There are some problems in traditional Fieldbus Technology of flexible production line, such as the high request of the total control machine configuration, the large resources cost of the configuration software, the data should be regularly cleaned. This paper introduces a new type flexible manufacturing system (FMS architecture based on ARM. The control core of the system is Samsung's S3C2440 ARM micro processor, which enhanced the reliability of the system, Join monitoring equipment and wireless communication equipment, facilitate real-time monitoring and image collection, and ensure the safety of the unattended. The numerical control processing unit is based of industrial PC and movement control card form, which enhanced the openness of the CNC system, and improved the communication function of the numerical control system. The experiment proved that this scheme overcome the problems existing in the traditional FMS.

Xiaoqing Tian

2012-12-01

322

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

323

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

324

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

325

Dual arm robotic system with sensory input  

Science.gov (United States)

The need for dual arm robots in space station assembly and satellite maintainance is of increasing significance. Such robots will be in greater demand in the future when numerous tasks will be assigned to them to relieve the direct intervention of humans in space. Technological demands from these robots will be high. They will be expected to perform high speed tasks with a certain degree of autonomy. Various levels of sensing will have to be used in a sophisticated control scheme. Ongoing research in control, sensing and real-time software to produce a two-arm robotic system than can accomplish generic assembly tasks is discussed. The control hierarchy and the specific control approach are discussed. A decentralized implementation of model-reference adaptive control using Variable Structure controllers and the incorporation of tactile feedback is considered.

Ozguner, U.

1987-01-01

326

Special Gripper for a Robotic Arm  

Directory of Open Access Journals (Sweden)

Full Text Available New structures for gripping objects in robotic manipulation processes are oriented to the new arrangement of mechanical structures using new materials and processing technologies and innovative procedures for the implementation of contact gripping element links to an object with a high degree of adaptively of applications together with the ability to alter the structure of grip and limiting the intensity of the contact stiffness variation of snap elements custody and pliability. The application of elastomeric materials and surface finishes is important. This paper presents both a new gripper design for robot arms but also the search of the selected materials to make an experimental evaluation of technical parameters that are used to assess their application potential and suitability for the targeted applications. Also the results and conclusions for gripper testing in manipulation operations with two different robot arms are presented.

Miguel Angel SELLES

2012-12-01

327

Parallelization algorithms for modeling ARM processes  

Directory of Open Access Journals (Sweden)

Full Text Available AutoRegressive Modular (ARM processes are a new class of nonlinear stochastic processes, which can accurately model a large class of stochastic processes, by capturing the empirical distribution and autocorrelation function simultaneously. Given an empirical sample path, the ARM modeling procedure consists of two steps: a global search for locating the minima of a nonlinear objective function over a large parametric space, and a local optimization of optimal or near optimal models found in the first step. In particular, since the first task calls for the evaluation of the objective function at each vector of the search space, the global search is a time consuming procedure. To speed up the computations, parallelization of the global search can be effectively used by partitioning the search space among multiple processors, since the requisite communication overhead is negligible.

Benjamin Melamed

2000-01-01

328

Shoulder abduction moment arms in three clinically important positions.  

Science.gov (United States)

The abduction moment arms of 4 shoulder muscles were calculated in clinically important positions to evaluate the best test situation for the supraspinatus based on its mechanical advantage.Moment arms of the supraspinatus, infraspinatus, and middle and anterior deltoid in 18 individuals were computed using individual magnetic resonance imaging data and a computer-assisted design tool for simulation. Three tests with the arm in the neutral position (arm hanging on side), at 90 of scaption,and at 90 of scaption and full internal humeral rotation (Jobe test) were investigated. The supraspinatushas a greater mechanical advantage vs the other tested muscles in the neutral arm position. In the Jobe position, the supraspinatus' abduction moment arm is reduced with increased internal humeral rotation.Comparing these results with the literature indicates that this new method is adequate for calculation of moment arms and may be used in any desired joint configuration. PMID:19655429

Ruckstuhl, Heidi; Krzycki, Jacek; Petrou, Nassos; Favre, Philippe; Horn, Tamara; Schmid, Stefan; Stussi, Edgar

2009-01-01

329

About the principles of armed conflicts rights  

International Nuclear Information System (INIS)

The international instruments approved in relation to restriction of war right are studied and their relevant clauses are interpreted in the article. The author lists the principles of choosing the ways and methods of conducting the war, and states that at present one of the aspects for regulation of the armed conflicts from the international and legal standpoint is to implement the operations for protection of peace or good will operations as well

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

ARMED FORCES AND INTERVENTION IN TROPICAL AFRICA  

OpenAIRE

"The Ghana Armed Forces, in co-operation with the police, have thought it necessary to take over the reins of power and to dismiss the former President, Kwame Nkrumah, the Presidential Commission and all Ministers, and to suspend the Constitution and to dissolve Parliament. This act has been necessitated by the political and economic situation in the country. The concentration of power in the hands of one man has led to the abuse of individual rights and liberty. Power has been exercis...

Steyn, L.; Baynham, S. J.

2012-01-01

332

Planar Robot Arm Modelling and Control  

OpenAIRE

The thesis objective is to model a one link robotic arm mounted on a sliding mobile platform and to investigate different control strategies under the effect of gravity and external force disturbance. For simplicity the robotic set up can be modelled and controlled as an inverted pendulum moving on a non constant sloping surface. Firstly the control is done on level ground. This lower mathematical complexity will be taken as an advantage to approach the analysis on aspects more related with c...

Herna?ndez Gonza?lez, Francisco

2012-01-01

333

Automation Using Robotic Arm in Rotor Packaging  

OpenAIRE

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 proj...

Gopu, G.; Arjun Shiby, M.; Naga Arjun, M.; Shashank, R.; Sinan, V.

2013-01-01

334

Command and control in Slovenian Armed Forces  

OpenAIRE

Present Master's Works deals with the topic of command and control in Slovenian armed forcis. The domain of the issue has been introduced to further research only recently, and is therefor topical and useful especialy for the profession which, so far has not engaged specialists in discussing the issue wholly. The domain of command and control is currently developing intensively. Since the outset of developement, there have been many different opinions on how to define the concept of comma...

Pelaj, Avdulla

2009-01-01

335

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

336

Low Temperature Syntheses of Metastable Nickel Germanides  

Science.gov (United States)

Two phases, Ni5Ge2 and NiGe2, were synthesized from modulated elemental reactant precursors. The atomic composition and thickness of the multilayer precursors were chosen so that interdiffusion precedes nucleation. X-ray reflectivity reveals layering immediately after deposition, and then after subsequent annealing, complete interdiffusion occurs before crystallization. Grazing incidence x-ray diffraction identified the formation of the metastable NiGe2 phase and high temperature Ni5Ge2 phase at low temperature ( 200C) and ambient pressure. We believe this is the first reported syntheses of these metastable phases under such mild conditions. Supporting data and a dicussion of the synthesis technique will be presented.

Ly, Sochetra; Jensen, Jacob M.; Johnson, David C.

2003-05-01

337

Syntheses and studies of organosilicon compounds  

Energy Technology Data Exchange (ETDEWEB)

The syntheses of polycarbosilanes and polysilanes as silicon carbide ceramic precursors have been active research areas in the Barton Research Group. In this thesis, the work is focused on the preparation of polycarbosilanes and polysilanes as stoichiometric silicon carbide precursor polymers. The syntheses of the precursor polymers are discussed and the conversions of these precursors to silicon carbide via pyrolysis are reported. The XRD pattern and elemental analyses of the resulting silicon carbide ceramics are presented. Silicon monoxide is an important intermediate in the production of silicon metal. The existence of silicon monoxide in gap phase has been widely accepted. In the second part of this thesis, the generation of gaseous silicon monoxide in four different reactors and the reactions of gaseous silicon monoxide towards organic compounds are discussed.

Xie, R.

1999-02-12

338

Peptide and peptide nucleic acid syntheses using a DNA/RNA synthesizer.  

Science.gov (United States)

The use of an ABI 394 DNA/RNA synthesizer for peptide and peptide nucleic acid (PNA) syntheses is described. No additional physical part or software is needed for the application. A commercially available large DNA synthesis column was used, and only about half of its volume was filled with resin when the resin was fully swollen. With additional space in the top portion of the column, agitation of reaction mixture was achieved by bubbling argon from the bottom without losing solution. Removing solutions from column was achieved by flushing argon from top to bottom. Two peptide and two PNA sequences were synthesized. Good yields were obtained in all the cases. The method is easy to follow by researchers who are familiar with DNA/RNA synthesizer. © 2014 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 102: 487-493, 2014. PMID:25298082

Pokharel, Durga; Fueangfung, Suntara; Zhang, Mingcui; Fang, Shiyue

2014-11-01

339

Landsat observations in support of ARM  

Energy Technology Data Exchange (ETDEWEB)

Compare results from state-of-the-art 3D radiative transfer techniques on a variety of input cloud fields with a wide degree of complexity. The goal of this proposal is to compare results from state-of-the-art 3D radiative transfer techniques on a variety of input cloud fields with a wide degree of complexity. This effort will complement ongoing cloud-related efforts of the GCSS working groups, and DoE-ARM Single Column Modeling and Cloud working groups. The intercomparison will be beneficial in delineating the limits and merits of the various approaches currently used to treat 3D radiative transfer theory and will create a broader consensus on what are the most serious remote sensing errors due to 3D effects. Realistic cloud water distributions used as input for many of the experiments will come directly from the ARM archive or from ARM-related modeling activities (such as those in progress as part of GCSS).

Cahalan, R.

2003-06-04

340

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

341

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

342

The arm motion detection (AMD) test.  

Science.gov (United States)

Stroke can lead to sensory deficits that impair functional control of arm movements. Here we describe a simple test of arm motion detection (AMD) that provides an objective, quantitative measure of movement perception related proprioceptive capabilities in the arm. Seven stroke survivors and thirteen neurologically intact control subjects performed the AMD test. In a series of ten trials that took less than 15 minutes to complete, participants used a two-button user interface to adjust the magnitude of hand displacements produced by a horizontal planar robot until the motions were just perceptible (i.e. on the threshold of detection). The standard deviation of movement detection threshold was plotted against the mean and a normative range was determined from the data collected with control subjects. Within this normative space, subjects with and without intact proprioception could be discriminated on a ratio scale that is meaningful for ongoing studies of degraded motor function. Thus, the AMD test provides a relatively fast, objective and quantitative measure of upper extremity proprioception of limb movement (i.e. kinesthesia). PMID:25571202

Bengtson, Maria C; Mrotek, Leigh A; Stoeckmann, Tina; Ghez, Claude; Scheidt, Robert A

2014-08-01

343

ARM9 Based Navigation System for Vehicles  

Directory of Open Access Journals (Sweden)

Full Text Available Vehicle Navigation System is one of the most challenging works today. If any accidents happen then if we know nearest hospital, route to reach hospital then we can have more chance to rescue people. Our project is an attempt to develop Vehicle Navigation System using ARM9 Processor, GPS and Electronic Compass. Usage of our project can be to guide the sailor in ocean, guide tourists and guide taxi drivers in major and metropolitan cities. Here using the ARM processor and the embedded operating system WindowsCE as a development platform for designing navigation systems. The system uses GPS systems to obtain the latitude and longitude of the vehicles, by conversion and map-matching to get the actual location on the map, and then the user enter the destination, calculated the shortest path by A* shortest path algorithm and showed on the ARM processor. At the same time, direct of vehicle is extracted from electronic compass providing the direction of vehicle and displayed on the screen.

S. Lokesh*1,

2014-05-01

344

Synthese und Charakterisierung von molekularen Nanostrukturen  

OpenAIRE

In this thesis, bulk and local scale spectroscopic and microscopic tools have been applied to investigate the purified raw material of SWCNT and synthesized MWBNNT, BN-nanocapsules, B-doped SWCNT and SiC nanostructures. Using bulk scale sensitive techniques, including optical absorption spectroscopy, Raman spectroscopy, high-resolution electron energy-loss spectroscopy, the average response of the whole sample is obtained. On the other hand, on a local scale transmission and scanning electron...

Borowiak-palen, Ewa

2004-01-01

345

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

346

HIMAC RF system with a digital synthesizer  

International Nuclear Information System (INIS)

An RF acceleration system, in which digital control with a direct digital synthesizer (DDS) is applied, has been developed for the Heavy Ion Medical Accelerator in Chiba (HIMAC) synchrotron. This digital system allows us to obtain stable operation of the acceleration system over a wide frequency range from 1.04 to 7.9 MHz. In this paper the designed digital RF control system and its performance are described

347

Piezoresistance in chemically synthesized polypyrrole thin films  

OpenAIRE

The resistance of chemically synthesized polypyrrole (PPy) thin films is investigated as a function of the pressure of various gases as well as of the film thickness. A physical, piezoresistive response is found to coexist with a chemical response if the gas is chemically active, like, e.g., oxygen. The piezoresistance is studied separately by exposing the films to the chemically inert gases such as nitrogen and argon. We observe that the character of the piezoresistive resp...

Barnoss, S.; Shanak, H.; Bufon, C. Bof; Heinzel, T.

2009-01-01

348

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)

349

Syntheses and studies of acetylenic polymers  

Energy Technology Data Exchange (ETDEWEB)

Based on new diiodo aryl compounds a series of novel soluble polymers, poly(2,5-dialkoxy-1,4-phenyleneethynylene)s (PPE polymers) were synthesized using palladium-catalysis. The molecular weights (MW) range from 8,000 to 40,000. Properties such as absorption, fluorescence, and conductivity were studied. A PPE polymer with butoxy side chain exhibits a weak electrical conductivity ({sigma} = 10{sup {minus}3} S/cm) after doping with AsF{sub 5}. Absorption spectra in THF solution at room temperature (RT) show a maximum at 440 nm. However, absorption spectra of PPE polymers in the film state at (RT) show a maximum at 480 nm. PPE polymer-based light emitting diode (LED) devices have been prepared; greenish light from these LED devices can be observed. Poly(ethynylene-p-arylene-ethynylene-silylene)s were synthesized through the same palladium-catalyzed polymerization; MWs are between 6,000 and 82,000. Absorption and fluorescence were studied. Some of these polymers exhibit thermotropic liquid crystalline properties. In addition, nonlinear optical properties were briefly examined. Poly(silylene-ethynylene) homopolymers as well as alternating copolymers were synthesized through a novel palladium-catalyzed polymerization; MWs range from 56 {times} 10{sup 3} to 5.3 {times} 10{sup 3}. Thermal stability of these was also investigated; char yields range from 56 to 83%. One of these polymers exhibits thermotropic liquid crystalline properties.

Yiwei, Ding

1994-03-03

350

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

351

Template Syntheses, Crystal Structures and Supramolecular Assembly of Hexaaza Macrocyclic Copper(II) Complexes  

Energy Technology Data Exchange (ETDEWEB)

Two new hexaaza macrocyclic copper(II) complexes were prepared by a template method and structurally characterized. In the solid state, they were self-assembled by intermolecular interactions to form the corresponding supramolecules 1 and 2, respectively. In the structure of 1, the copper(II) macrocycles are bridged by a tp ligand to form a macrocyclic copper(II) dimer. The dimer extends its structure by intermolecular forces such as hydrogen bonds and C-H···? interactions, resulting in the formation of a double stranded 1D supramolecule. In 2, the basic structure is a monomeric copper(II) macrocycle with deprotonated imidazole pendants. An undulated 1D hydrogen bonded array is achieved through hydrogen bonds between imidazole pendants and secondary amines, where the imidazole pendants act as a hydrogen bond acceptor. The 1D hydrogen bonded supramolecular chain is supported by C-H···? interactions between the methyl groups of acetonitrile ligands and imidazole pendants of the copper(II) macrocycles. In both complexes, the introduction of imidazoles to the macrocycle as a pendant plays an important role for the formation of supramolecules, where they act as intermolecular hydrogen bond donors and/or acceptors, C-H···? and ?-? interactions.

Kim, Taehyung; Kim, Ju Chang [Pukyong National Univ., Busan (Korea, Republic of); Lough, Alan J. [Univ. of Toronto, Toronto (Canada)

2013-06-15

352

Template Syntheses, Crystal Structures and Supramolecular Assembly of Hexaaza Macrocyclic Copper(II) Complexes  

International Nuclear Information System (INIS)

Two new hexaaza macrocyclic copper(II) complexes were prepared by a template method and structurally characterized. In the solid state, they were self-assembled by intermolecular interactions to form the corresponding supramolecules 1 and 2, respectively. In the structure of 1, the copper(II) macrocycles are bridged by a tp ligand to form a macrocyclic copper(II) dimer. The dimer extends its structure by intermolecular forces such as hydrogen bonds and C-H···? interactions, resulting in the formation of a double stranded 1D supramolecule. In 2, the basic structure is a monomeric copper(II) macrocycle with deprotonated imidazole pendants. An undulated 1D hydrogen bonded array is achieved through hydrogen bonds between imidazole pendants and secondary amines, where the imidazole pendants act as a hydrogen bond acceptor. The 1D hydrogen bonded supramolecular chain is supported by C-H···? interactions between the methyl groups of acetonitrile ligands and imidazole pendants of the copper(II) macrocycles. In both complexes, the introduction of imidazoles to the macrocycle as a pendant plays an important role for the formation of supramolecules, where they act as intermolecular hydrogen bond donors and/or acceptors, C-H···? and ?-? interactions

353

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

354

Carbon spheres synthesized by ultrasonic treatment  

International Nuclear Information System (INIS)

Onion-like carbon nanospheres have been synthesized through ultrasound treatment on highly oriented pyrolytic graphite (HOPG) material in deion water. High resolution transmission electron microscope (HRTEM) and electron diffraction (ED) analyses show that these nanospheres are composed of disordered lattice lines of graphene sheets and the size of them ranges from about 10 nm to 200 nm. In addition, to explain the growth mechanism of carbon nanospheres, one possible two-stage model was proposed of nucleus formation and 'rolling snowball' growth of carbon nanospheres

355

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)

356

Synthese von Modellkatalysatoren für industrielle Anwendungen  

OpenAIRE

Different one-pot approach methods are used to synthesize metal oxide nanoparticles (MONPs) and noble metal nanoparticles (NMNPs) for specific catalytic applications. A solid solution of NixMn1-xO supported on porous silica is obtained by a one-pot approach, a combination of co-precipitation and the sol-gel process. Through adjusting the pH to 10, the gelation of sodium metasilicate is controlled at a low rate, which contributes to the high dispersion of metal precursors and subsequent formin...

Xie, Xiao

2014-01-01

357

Syntheses of deuterium labeled bile alcohols  

International Nuclear Information System (INIS)

The following major bile alcohols, identified in urine of healthy humans and in bile and urine of patients with cerebrotendinous xanthomatosis, were synthesized as internal standards for mass spectral analyses: [26,27-D6]5?-cholestane-3?, 7?, 12?, 25-tetrol, [26,27-D6](23S)-5?-cholestane-3?, 7?, 12?, 23,25-pentol, [27-D3]5?-cholestane-3?, 7?, 12?, 25,26-pentol, and [2,4-D4]27-nor-5?-cholestane-3?, 7?, 12?, 24, 25-pentol. (author)

358

Helical gold nanotube synthesized at 150 K.  

Science.gov (United States)

Gold nanowires were synthesized at 150 K by electron beam thinning of a gold thin foil in an UHV electron microscope. The gold nanowires were found to have a helical multishell structure (HMS). One particular nanowire, which was thinner than the 7-1 HMS nanowire, was found to have a tubular structure. The gold single wall nanotube is composed of five atomic rows that coil about the tube axis. The diameter was 0.4 nm and the pitch was 11 nm. The stability of the (5,3) nanotube was discussed in terms of the shear deformation of the triangular network of gold atoms. PMID:14683374

Oshima, Yoshifumi; Onga, Akiko; Takayanagi, Kunio

2003-11-14

359

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,part of the Soviet Union---a total of 240,000 men, 10,000 tanks, 9,500 artillery systems, and 800 combat aircraft

360

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 mainfrom 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)

361

Safety evaluation of the rocker arm of a diesel engine  

International Nuclear Information System (INIS)

In order to evaluate the fatigue endurance for the rocker arm of a diesel engine, stress measurements were performed using strain gages attached near the neck, which is one of the most critical regions in the rocker arm, while varying the engine speed. Fatigue life experiments were carried out on miniature specimens taken from rocker arms. To evaluate the fatigue endurance of the rocker arm, the S-N data were compared with the stress analysis results obtained through a Finite Element Modelling (FEM) analysis of the rocker arm. The von-Mises effective stress of the rocker arm neck region was determined to be 22.4 MPa. The safety factors of this component are 2.6 and 3.8, based on the fatigue endurance limit and the modified fatigue endurance limit, respectively, suggesting that this safety factor is appropriate.

362

TRIGGERED STAR FORMATION IN SPIRAL ARMS  

Directory of Open Access Journals (Sweden)

Full Text Available We present the status of our research, relative to the triggering of star formation by large-scale galactic shocks associated with spiral density waves. Around a third of the galaxies in our sample do not seem suitable for this kind of study, because they present an e ect, probably due to opacity, that is not well understood. The remaining objects seem to favor the idea of density wave triggering of star formation in the arms. The comparison with stellar population synthesis models, and the orbital resonance positions for these galaxies (derived by means of spiral pattern angular speeds corroborate this hypothesis.

E. E. Mart\\u00EDnez-Garc\\u00EDa

2009-01-01

363

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

364

ARM9 Based Embedded E-Documentation  

OpenAIRE

Among the huge population of India many people facing the headache of the government documents. Unwillingly they have to pay extra money and extra time for these documents though it is our basic right to get it free and urgent! This project is proposed to achieve the main goals of anti-corruption system for government documents needed for common people in day to day life. Our project basically includes four main parts, a fingerprint detector, ARM-9 control unit, PC with touch screen GUI and i...

Sachin S; , Sachin D. Anap, Amruta M. Kulkarni, Mahesh D. Nirmal, T.A.More,Taware, Sanjay G. Galande

2012-01-01

365

Critical configurations of planar robot arms  

CERN Document Server

It is known that a closed polygon P is a critical point of the oriented area function if and only if P is a cyclic polygon, that is, $P$ can be inscribed in a circle. Moreover, there is a short formula for the Morse index. Going further in this direction, we extend these results to the case of open polygonal chains, or robot arms. We introduce the notion of the oriented area for an open polygonal chain, prove that critical points are exactly the cyclic configurations with antipodal endpoints and derive a formula for the Morse index of a critical configuration.

Khimshiashvili, G; Siersma, D; Zhukova, A

2012-01-01

366

Rasp Tool on Phoenix Robotic Arm Model  

Science.gov (United States)

This close-up photograph taken at the Payload Interoperability Testbed at the University of Arizona, Tucson, shows the motorized rasp protruding from the bottom of the scoop on the engineering model of NASA's Phoenix Mars Lander's Robotic Arm. The rasp will be placed against the hard Martian surface to cut into the hard material and acquire an icy soil sample for analysis by Phoenix's scientific instruments. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is led by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

2008-01-01

367

Robotic Arm-The Ball Catcher  

OpenAIRE

Catching a thrown ball with a hand is not easy – neither for humans nor for robots. It demands for a tight interplay of skills in mechanics, control, planning and visual sensing to reach the necessary precision in space and time. Because of this, ball catching has been used for almost 20 years now as a challenging benchmark system to develop and test robotics key technologies. Here we propose a high speed and intelligent robotic arm set up which will capable enough to catch the short range ...

Titarmare, J. C.; Katkar, M. D.; Agrawal, A. J.

2014-01-01

368

Partial monosomy of chromosome 10 short arms.  

OpenAIRE

Two children with monosomy 10p13 are reported. In the first case the monosomy was the result of a maternal balanced translocation t(3;10) (p27;p13) while the second case was a de novo mutation. We reviewed clinical details of cases reported so far and found that certain symptoms are typical of the deletion of a comparatively large segment of chromosome 10 short arms. These symptoms include mental and growth retardation, skull abnormalities, antimongoloid slant of the eyes, ear abnormalities, ...

Genci?k, A.; Bro?nniman, U.; Tobler, R.; Auf Maur, P.

1983-01-01

369

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

OpenAIRE

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

370

Bounded Regret for Finite-Armed Structured Bandits  

OpenAIRE

We study a new type of K-armed bandit problem where the expected return of one arm may depend on the returns of other arms. We present a new algorithm for this general class of problems and show that under certain circumstances it is possible to achieve finite expected cumulative regret. We also give problem-dependent lower bounds on the cumulative regret showing that at least in special cases the new algorithm is nearly optimal.

Lattimore, Tor; Munos, Remi

2014-01-01

371

A Global Obstacle-avoidance Map for Anthropomorphic Arms  

OpenAIRE

More and more humanoid robots are used in human society, and they face a wide variety of complicated manipulation tasks, which are mainly to be achieved by their anthropomorphic arms. Obstacle avoidance for the anthropomorphic arm must be a fundamental consideration to guarantee the successful implementation of these tasks. Different from traditional methods searching for feasible or optimal collision-free solutions for the anthropomorphic arm, a global obstacle- avoidance map for the whole a...

Cheng Fang; Xilun Ding

2014-01-01

372

Controlling a Robotic Arm manipulator with a PLC  

OpenAIRE

ABSTRACT This thesis was commissioned for HAMK University of Applied Sciences with the aim of designing a control system for a robotic arm. The Robotic Arm in this case was from HAMK’s Laboratory for Automation, Riihimäki which was designed by Nicolas Mustaka (an exchange student from Greece, 2009). The main objective of this thesis was to design a control system for the Robotic Arm using a programmable logic controller (PLC) and to construct a gripper. The control system design ...

Lama, Bhim

2008-01-01

373

The crimes of recruiting and using children in armed conflict  

OpenAIRE

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...

Greijer, Susanna

2013-01-01

374

Design and Analysis of Rotating Bucket Arm of Excavator  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper an attempt has been made to design and analyze the rotating bucket of the excavator along with the stick and the bucket arm. This paper focuses on the joint design by using the geared motor for angular rotation of the bucket arm and studies the effect of digging, torsional force and bending stresses developed on the joint. Study the motion of the bucket arm

Bikash Rai

2013-12-01

375

Recent Advances in Chemoenzymatic Peptide Syntheses  

Directory of Open Access Journals (Sweden)

Full Text Available Chemoenzymatic peptide synthesis is the hydrolase-catalyzed stereoselective formation of peptide bonds. It is a clean and mild procedure, unlike conventional chemical synthesis, which involves complicated and laborious protection-deprotection procedures and harsh reaction conditions. The chemoenzymatic approach has been utilized for several decades because determining the optimal conditions for conventional synthesis is often time-consuming. The synthesis of poly- and oligopeptides comprising various amino acids longer than a dipeptide continues to pose a challenge owing to the lack of knowledge about enzymatic mechanisms and owing to difficulty in optimizing the pH, temperature, and other reaction conditions. These drawbacks limit the applications of the chemoenzymatic approach. Recently, a variety of enzymes and substrates produced using recombinant techniques, substrate mimetics, and optimal reaction conditions (e.g., frozen aqueous media and ionic liquids have broadened the scope of chemoenzymatic peptide syntheses. In this review, we highlight the recent advances in the chemoenzymatic syntheses of various peptides and their use in developing new materials and biomedical applications.

Kenjiro Yazawa

2014-09-01

376

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

377

Human retinas synthesize and release acetylcholine.  

Science.gov (United States)

Human retinas have the capacity to synthesize and release [3H]acetylcholine ([3H]ACh) after an incubation in [3H]choline ([3H]Ch). Synthesis of [3H]Ch by retinal homogenates was determined using either high-voltage paper electrophoresis (HVPE) or a two-step enzymatic/extraction assay for separating [3H]ACh from [3H]Ch. The enzymatic/extraction assay is shown to be accurate over a wide range of concentrations (10(-6)-10(-12) M). Homogenates of human retina synthesize [3H]ACh from [3H]Ch. We find an approximate Km of 50 microM and a Vmax of about 20 nmol/mg protein/h (at 37 degrees C) for the synthesis of labeled ACh by retinal homogenates. Human retinas also release [3H]ACh after a pulse of [3H]Ch. Release of labeled transmitter is stimulated by potassium depolarization. The potassium-stimulated release is partially blocked by magnesium or cobalt ions. Release data were analyzed by both the enzymatic/extraction assay and HVPE; the results are qualitatively identical in both cases. The data reported here provide additional evidence for cholinergic neurotransmission in the human retina. PMID:3711912

Hutchins, J B; Hollyfield, J G

1986-07-01

378

Recent advances in chemoenzymatic peptide syntheses.  

Science.gov (United States)

Chemoenzymatic peptide synthesis is the hydrolase-catalyzed stereoselective formation of peptide bonds. It is a clean and mild procedure, unlike conventional chemical synthesis, which involves complicated and laborious protection-deprotection procedures and harsh reaction conditions. The chemoenzymatic approach has been utilized for several decades because determining the optimal conditions for conventional synthesis is often time-consuming. The synthesis of poly- and oligopeptides comprising various amino acids longer than a dipeptide continues to pose a challenge owing to the lack of knowledge about enzymatic mechanisms and owing to difficulty in optimizing the pH, temperature, and other reaction conditions. These drawbacks limit the applications of the chemoenzymatic approach. Recently, a variety of enzymes and substrates produced using recombinant techniques, substrate mimetics, and optimal reaction conditions (e.g., frozen aqueous media and ionic liquids) have broadened the scope of chemoenzymatic peptide syntheses. In this review, we highlight the recent advances in the chemoenzymatic syntheses of various peptides and their use in developing new materials and biomedical applications. PMID:25191871

Yazawa, Kenjiro; Numata, Keiji

2014-01-01

379

Syntheses and radiobrominations of some trimethylsilylphenethylamines  

International Nuclear Information System (INIS)

Studies of the applications of arylsilane intermediates to radiobrominations have continued with the syntheses of four trimethylsilyl(TMS) substituted phenethylamines. Initial radiobromination studies have involved the nonprotected amines to determine if the ipso electrophilic substitution reactions would occur prior to reaction of the halogen with the amine. Indeed, radiobrominations of 1,2,and4 using carrier-added bromine-77 and stoichiometric amounts of N-chlorosuccinimide (NCS) gave the desired products in good yields. Radiobrominations of 3 under identical reaction conditions yielded a product which was consistent with compound 9 by chromatographic and spectroscopic analyses. When the oxidizing agent was used in excess of bromide ion, a significant amount of a more lipophlic radiobrominated compound was also observed by radio HPLC. The lipophilic compound was the major product when t-BuOCl was used as the oxidant, but was only a minor product when NCS was used. The syntheses of the phenethylamines, 1-8, was accomplished via standard methods (e.g. Knoevenagel Reaction), and is described

380

Syntheses and radiobrominations of some trimethylsilylphenethylamines  

Energy Technology Data Exchange (ETDEWEB)

Studies of the applications of arylsilane intermediates to radiobrominations have continued with the syntheses of four trimethylsilyl(TMS) substituted phenethylamines. Initial radiobromination studies have involved the nonprotected amines to determine if the ipso electrophilic substitution reactions would occur prior to reaction of the halogen with the amine. Indeed, radiobrominations of 1,2,and4 using carrier-added bromine-77 and stoichiometric amounts of N-chlorosuccinimide (NCS) gave the desired products in good yields. Radiobrominations of 3 under identical reaction conditions yielded a product which was consistent with compound 9 by chromatographic and spectroscopic analyses. When the oxidizing agent was used in excess of bromide ion, a significant amount of a more lipophlic radiobrominated compound was also observed by radio HPLC. The lipophilic compound was the major product when t-BuOCl was used as the oxidant, but was only a minor product when NCS was used. The syntheses of the phenethylamines, 1-8, was accomplished via standard methods (e.g. Knoevenagel Reaction), and is described.

Wilbur, D.S.

1984-01-01

381

ANOMALOUS BRANCHES OF MEDIAN NERVE IN THE ARM  

Directory of Open Access Journals (Sweden)

Full Text Available Background: Dissection of right and left upper limbs and demonstration of the origin and the course of median nerve. Result: Median nerve in the right upper limb is formed normally but it supplies brachialis muscle and both head of the biceps in the arm which is anomalous. In the left arm of the patient the course and supply of median nerve is normal. Conclusion: The patient has unilateral anomalous supply of median nerve in the arm – this can result in trauma to this nerve while undergoing any surgery in right arm.

Ishita Ghosh

2014-11-01

382

Haemoglobin saturation during incremental arm and leg exercise.  

OpenAIRE

There are few reports concerning the alterations in the percent of haemoglobin saturated with oxygen (%SO2) during non-steady state incremental exercise. Further, no data exist to describe the %SO2 changes during arm exercise. Therefore, the purpose of this study was made to assess the dynamic changes in %SO2 during incremental arm and leg work. Nine trained subjects (7 males and 2 females) performed incremental arm and leg exercise to exhaustion on an arm crank ergometer and a cycle ergomete...

Powers, S. K.; Dodd, S.; Woodyard, J.; Beadle, R. E.; Church, G.

1984-01-01

383

Spiral arm structures revealed in the M31 galaxy  

OpenAIRE

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

384

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

385

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

386

Learning to play K-armed bandit problems  

OpenAIRE

We propose a learning approach to pre-compute K-armed bandit playing policies by exploiting prior information describing the class of problems targeted by the player. Our algorithm ?rst samples a set of K-armed bandit problems from the given prior, and then chooses in a space of candidate policies one that gives the best average performances over these problems. The candidate policies use an index for ranking the arms and pick at each play the arm with the highest index; the index for each ...

Maes, Francis; Wehenkel, Louis; Ernst, Damien

2012-01-01

387

A prototype cryogenic pickoff arm for multi-IFU spectrometers  

Science.gov (United States)

A prototype cryogenic "pick-off" arm for selecting a small field from the focal plane of a large telescope has been designed, built and tested against a set of scientific requirements representative of those for proposed multi-integral-field spectrographs. In this paper, we present the design of the arm and the results of the cryogenic testing. Since the proposed instruments will require tens of arms, perhaps hundreds, we have also considered the industrialisation of the manufacture and build of the arms. We briefly discuss this aspect of the design and the possibilities for future instrumentation on Extremely Large Telescopes.

Dowling, M.; McMahon, P.; Ramsay Howat, S.; Robertson, D. J.; Parr-Burmann, P.; Sharples, R.; Cunnigham, C.; Dickson, C.; Schmoll, J.; Hastings, P.; Lee, D.; Luke, P.; Phillips, N.; Wells, M.; Dipper, N.

2005-07-01

388

Spur reduction techniques for fractional-N frequency synthesizers  

OpenAIRE

Frequency synthesizer is an essential circuit block for up conversion and down conversion in transmitters and receivers respectively. Fractional-N frequency synthesizers are replacing conventional integer- N frequency synthesizers because of their better performance in terms of settling time and phase noise. However, fractional-N frequency synthesizers suffer from fractional spurs or side bands which increase errorvector magnitude (EVM). To solve the fractional spur problem various technique...

Ahmad, Fazil

2010-01-01

389

Arm insulation and swimming in cold water.  

Science.gov (United States)

To test whether adding insulation to the arms would improve cold water swimming performance by delaying swimming failure (SF). Novice (n = 7) and expert (n = 8) swimmers, clothed and equipped with a personal flotation device, each performed two trials in a swimming flume filled with 10 degrees C water. During free swimming (FS), subjects performed swimming until failure, followed by the Heat Escape Lessening Posture. In free swimming with additional insulation (FSA), subjects wore custom-fitted armbands. Trials ended when rectal temperature decreased to 34 degrees C or after 2 h of immersion. Measurements included: rectal and skin temperatures, heat flow, and various appraisals of swimming performance. FSA was thermally advantageous versus FS. Rectal temperature cooling rates during swimming (dT/dt Swim) were faster for FS compared to FSA (0.050 +/- 0.007 degrees C min(-1) vs. 0.042 +/- 0.006 degrees C min(-1), P neoprene armbands appears to have partially preserved muscle function, but with unimpressive effects on overall performance. SF is a complex entity, but is evidently related to both triceps skinfold and arm girth. PMID:18309510

Lounsbury, David S; Ducharme, Michel B

2008-09-01

390

Robotic Arm-The Ball Catcher  

Directory of Open Access Journals (Sweden)

Full Text Available Catching a thrown ball with a hand is not easy – neither for humans nor for robots. It demands for a tight interplay of skills in mechanics, control, planning and visual sensing to reach the necessary precision in space and time. Because of this, ball catching has been used for almost 20 years now as a challenging benchmark system to develop and test robotics key technologies. Here we propose a high speed and intelligent robotic arm set up which will capable enough to catch the short range thrown ball in specified environment. The main technique used is a stereo vision system to tracks the ball and predicts the balls trajectory then the point and time required to reach at destination point, and in which orientation the robot should intercept the ball on its trajectory, is determined. Once robots calculate the desired parameters it will try to catch the ball. Expected outcome of the proposed system is to catch the ball by calculating the coming ball path using computer vision techniques and move the robotic arm in order to catch the ball

J.C.Titarmare

2014-02-01

391

ARM 7 BASED MP3 PLAYER  

Directory of Open Access Journals (Sweden)

Full Text Available MP3 is a patented encoding format for digital audio which uses a form of lossy data compression. It is a common audio format for consumer audio streaming or storage, as well as a de facto standard of digital audio compression for the transfer and playback of music on most digital audio players. Since the MPEG-1 Layer III encoding technology is nowadays widely used it might be interesting to gain knowledge of how this powerful compression/decompression scheme actually functions. The MPEG-1 Layer III is capable of reducing the bit rate with a factor of 12 without almost any audible degradation. Arm7 lpc2148 is arm7tdmi-s core board microcontroller that uses 16/32-bit 64 pin (lqfp microcontroller no.lpc2148 from Philips (nxp.The hardware system of lpc2148 includes the necessary devices within only one mcu has such as usb, adc, dac, timer/counter, pwm, capture, i2c, spi, uart, and etc.

Ashiq V Mehta

2014-02-01

392

Structured Molecular Gas Reveals Galactic Spiral Arms  

CERN Document Server

We explore the development of structures in molecular gas in the Milky Way by applying the analysis of the brightness distribution function (BDF) and the brightness distribution index (BDI) in the archival data from the Boston University-Five College Radio Astronomy Observatory 13CO 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 formati...

Sawada, Tsuyoshi; Koda, Jin

2012-01-01

393

ARM Climate Research Facility Annual Report 2004  

Energy Technology Data Exchange (ETDEWEB)

Like a rock that slowly wears away beneath the pressure of a waterfall, planet earth?s climate is almost imperceptibly changing. Glaciers are getting smaller, droughts are lasting longer, and extreme weather events like fires, floods, and tornadoes are occurring with greater frequency. Why? Part of the answer is clouds and the amount of solar radiation they reflect or absorb. These two factors clouds and radiative transfer represent the greatest source of error and uncertainty in the current generation of general circulation models used for climate research and simulation. The U.S. Global Change Research Act of 1990 established an interagency program within the Executive Office of the President to coordinate U.S. agency-sponsored scientific research designed to monitor, understand, and predict changes in the global environment. To address the need for new research on clouds and radiation, the U.S. Department of Energy (DOE) established the Atmospheric Radiation Measurement (ARM) Program. As part of the DOE?s overall Climate Change Science Program, a primary objective of the ARM Program is improved scientific understanding of the fundamental physics related to interactions between clouds and radiative feedback processes in the atmosphere.

Voyles, J.

2004-12-31

394

“ONE-POT” SYNTHESES OF MALONDIALDEHYDE ADDUCTS OF NUCLEOSIDES  

OpenAIRE

Short, “one-pot” syntheses of malondialdehyde adducts of deoxyguanosine, deoxyadenosine, and deoxycytidine are described. These syntheses proceed in improved yield and easier purification than previous syntheses and are well suited for the preparation of isotopically labeled nucleoside adducts for biomarker and metabolic studies.

Szekely, Jozsef; Wang, Hao; Peplowski, Katherine M.; Knutson, Charles G.; Marnett, Lawrence J.; Rizzo, Carmelo J.

2008-01-01

395

Synthesis and Characterization of New Chiral Monoanionic [ON] Ancillary Phenolate Ligands  

Directory of Open Access Journals (Sweden)

Full Text Available Three new chiral monoanionic [ON] ancillary phenolate ligands with varying pendant arms have been synthesized in moderate to high yields (50% - 85% via Mannich-type condensation reaction of chiral substituted phenol, formaldehyde and (+-bis-[(R-1-phenylethyl]amine. These new organic compounds were fully characterized via nuclear magnetic resonance spectroscopy (1H and 13C and elemental analysis. The newly synthesized ligands are suitable candidates for metal-catalyzed ring-opening of lactones and asymmetric catalysis.

Pascal Binda

2014-08-01

396

Electrocapillarity and zero-frequency differential capacitance at the interface between mercury and ionic liquids measured using the pendant drop method.  

Science.gov (United States)

The structure of ionic liquids (ILs) at the electrochemical IL|Hg interface has been studied using the pendant drop method. From the electrocapillarity (potential dependence of interfacial tension) differential capacitance (Cd) at zero frequency (in other words, static differential capacitance or differential capacitance in equilibrium) has been evaluated. The potential dependence of zero-frequency Cd at the IL|Hg interface exhibits one or two local maxima near the potential of zero charge (Epzc), depending on the cation of the ILs. For 1-ethyl-3-methylimidazolium tetrafluoroborate, an IL with the cation having a short alkyl chain, the Cdvs. potential curve has one local maximum whereas another IL, 1-octyl-3-methylimidazolium tetrafluoroborate, with the cation having a long alkyl chain, shows two maxima. These behaviors of zero-frequency Cd agree with prediction by recent theoretical and simulation studies for the electrical double layer in ILs. At negative and positive potentials far from Epzc, the zero-frequency Cd increases for both the ILs studied. The increase in zero-frequency Cd is attributable to the densification of ionic layers in the electrical double layer. PMID:25600288

Nishi, Naoya; Hashimoto, Atsunori; Minami, Eiji; Sakka, Tetsuo

2015-02-01

397

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

398

Study of sulfonated polyether ether ketone with pendant lithiated fluorinated sulfonic groups as ion conductive binder in lithium-ion batteries  

Science.gov (United States)

In an attempt to reduce the Li+ concentration polarization and electrolyte depletion from the electrode porous space, sulfonated polyether ether ketone with pendant lithiated fluorinated sulfonic groups (SPEEK-FSA-Li) is prepared and attempted as ionic conductivity binder. Sulfonated aromatic poly(ether ether ketone) exhibits strong adhesion and chemical stability, and lithiated fluorinated sulfonic side chains help to enhance the ionic conductivity and Li+ ion diffusion due to the charge delocalization over the sulfonic chain. The performances are evaluated by cyclic voltammetry, electrochemical impedance spectroscopy, charge-discharge cycle testing, 180° peel testing, and compared with the cathode prepared with polyvinylidene fluoride binder. The electrode prepared with SPEEK-FSA-Li binder forms the relatively smaller resistances of both the SEI and the charge transfer of lithium ion transport. This is beneficial to lithium ion intercalation and de-intercalation of the cathode during discharging-charging, therefore the cell prepared with SPEEK-FSA-Li shows lower charge plateau potential and higher discharge plateau potential. Compared with PVDF, the electrode with ionic binder shows smaller decrease in capacity with the increasing of cycle rate. Meanwhile, adhesion strength of electrode prepared with SPEEK-FSA-Li is more than five times greater than that with PVDF.

Wei, Zengbin; Xue, Lixin; Nie, Feng; Sheng, Jianfang; Shi, Qianru; Zhao, Xiulan

2014-06-01

399

[Aerobic methylobacteria are capable of synthesizing auxins].  

Science.gov (United States)

Obligately and facultatively methylotrophic bacteria with different pathways of C1 metabolism were found to be able to produce auxins, particularly indole-3-acetic acid (IAA), in amounts of 3-100 micrograms/ml. Indole-3-pyruvic acid and indole-3-acetamide were detected only in methylobacteria with the serine pathway of C1 metabolism, Methylobacterium mesophilicum and Aminobacter aminovorans. The production of auxins by methylobacteria was stimulated by the addition of tryptophan to the growth medium and was inhibited by ammonium ions. The methylobacteria under study lacked tryptophan decarboxylase and tryptophan side-chain oxidase. At the same time, they were found to contain several aminotransferases. IAA is presumably synthesized by methylobacteria through indole-3-pyruvic acid. PMID:11558269

Ivanova, E G; Doronina, N V; Trotsenko, Iu A

2001-01-01

400

Synthesized larmor precessions and particle density waves  

International Nuclear Information System (INIS)

Larmor precessions are conventionally looked upon as the effect of a local magnetic field on a localized particle. In contrast, in quantum mechanical particle beams the precessions are described as the interference beating between spin 'up' and 'down' extended partial waves. Using the combined action of a neutron interferometer and a spin flipper these partial wave states can be prepared in a radically different way from the usual 90deg spin flip process. It is found, nevertheless, that the Larmor frequency of these synthesized precessions is equal to the classical value, if observed by an observer traveling along the particle trajectory with the classical velocity of the particle. The same tools are also shown to allow us to prepare neutron beams displaying coherent particle density waves on macroscopic space-time scale, a surprising new quantum phenomenon. Experimental verification of these predictions is in progress at the Hahn-Meitner-Institut. (author)

401

Chemically synthesized hollow nanostructures in iron oxides  

Science.gov (United States)

In this work, we report a detailed study of the formation of hollow nanostructures in iron oxides. Core/shell Fe/Fe-oxide nanoparticles were synthesized by thermal decomposition of Fe(CO)5 at high temperature. It was found that 8 nm is the critical size above which the particles have a core/shell morphology, whereas below this size the particles exhibit a hollow morphology. Annealing the core/shell particles under air also leads to the formation of hollow spheres with a significant increase in the average particle size. In the case of the thermally activated Kirkendall process, the particles do not fully transform into hollow structures but many irregular shaped voids exist inside each particle. The 8 nm hollow particles are superparamagnetic at room temperature with a blocking temperature of 70 K whereas the core/shell particles are ferromagnetic.

Khurshid, Hafsa; Li, Wanfeng; Tzitzios, Vasillis; Hadjipanayis, George C.

2011-07-01

402

Chemically synthesized hollow nanostructures in iron oxides  

Energy Technology Data Exchange (ETDEWEB)

In this work, we report a detailed study of the formation of hollow nanostructures in iron oxides. Core/shell Fe/Fe-oxide nanoparticles were synthesized by thermal decomposition of Fe(CO){sub 5} at high temperature. It was found that 8 nm is the critical size above which the particles have a core/shell morphology, whereas below this size the particles exhibit a hollow morphology. Annealing the core/shell particles under air also leads to the formation of hollow spheres with a significant increase in the average particle size. In the case of the thermally activated Kirkendall process, the particles do not fully transform into hollow structures but many irregular shaped voids exist inside each particle. The 8 nm hollow particles are superparamagnetic at room temperature with a blocking temperature of 70 K whereas the core/shell particles are ferromagnetic.

Khurshid, Hafsa; Li Wanfeng; Hadjipanayis, George C [Department of Physics and Astronomy, University of Deleware, DE 19716 (United States); Tzitzios, Vasillis, E-mail: hkhurshi@udel.edu [Institute of Materials Science, ' Demokritos' Agia Paraskevi 15310 Athens (Greece)

2011-07-01

403

Sorption of mercury on chemically synthesized polyaniline  

International Nuclear Information System (INIS)

Sorption of inorganic mercury (Hg2+) and methyl mercury, on chemically synthesized polyaniline, in 0.1-10N HCl solutions has been studied. Hg2+ is strongly sorbed at low acidities and the extent of sorption decreases with increase in acidity. The sorption of methyl mercury is very low in the HCl concentration range studied. Sorption of Hg2+ on polyaniline in 0.1-10N LiCl and H2SO4 solutions has also been studied. The analysis of the data indicates that the sorption of Hg2+ depends on the degree of protonation of polyaniline and the nature of mercury(II) chloride complexes in solution. X-ray photoelectron spectroscopy analysis (XPS) of polyaniline sorbed with mercury show that mercury is bound as Hg2+. Sorbed mercury is quantitatively eluted from polyaniline with 0.5N HNO3. Polyaniline can be used for separation and pre-concentration of inorganic mercury from aqueous samples. (author)

404

Simplification of Methods for PET Radiopharmaceutical Syntheses  

Energy Technology Data Exchange (ETDEWEB)

In an attempt to develop simplified methods for radiochemical synthesis of radiopharmaceuticals useful in Positron Emission Tomography (PET), current commercially available automated synthesis apparati were evaluated for use with solid phase synthesis, thin-film techniques, microwave-accelerated chemistry, and click chemistry approaches. Using combinations of these techniques, it was shown that these automated synthesis systems can be simply and effectively used to support the synthesis of a wide variety of carbon-11 and fluorine-18 labeled compounds, representing all of the major types of compounds synthesized and using all of the common radiochemical precursors available. These techniques are available for use to deliver clinically useful amounts of PET radiopharmaceuticals with chemical and radiochemical purities and high specific activities, suitable for human administration.

Kilbourn, Michael, R.

2011-12-27

405

Syntheses of deuterium labeled bile alcohols  

Energy Technology Data Exchange (ETDEWEB)

The following major bile alcohols, identified in urine of healthy humans and in bile and urine of patients with cerebrotendinous xanthomatosis, were synthesized as internal standards for mass spectral analyses: (26,27-D/sub 6/)5..beta..-cholestane-3..cap alpha.., 7..cap alpha.., 12..cap alpha.., 25-tetrol, (26,27-D/sub 6/)(23S)-5..beta..-cholestane-3..cap alpha.., 7..cap alpha.., 12..cap alpha.., 23,25-pentol, (27-D/sub 3/)5..beta..-cholestane-3..cap alpha.., 7..cap alpha.., 12..cap alpha.., 25,26-pentol, and (2,4-D/sub 4/)27-nor-5..beta..-cholestane-3..cap alpha.., 7..cap alpha.., 12..cap alpha.., 24, 25-pentol.

Kihira, Kenji; Kosaka, Daisaku; Une, Mizuho; Hiraoka, Toshihito; Kajiyama, Goro; Hoshita, Takahiko

1987-12-01

406

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

407

Synthesizing Earth's geochemical data for hydrogeochemical analysis  

Science.gov (United States)

For over 200 years, geochemical, microbiological, and chemical data have been collected to describe the evolution of the surface earth. Many of these measurements are data showing variations in time or in space. To forward predict hydrologic response to changing tectonic, climatic, or anthropogenic forcings requires synthesis of these data and utilization in hydrogeochemical models. Increasingly, scientists are attempting to synthesize such data in order to make predictions for new regions or for future time periods. However, to make such complex geochemical data accessible requires development of sophisticated cyberinfrastructures that both invite uploading as well as usage of data. Two such cyberinfrastructure (CI) initiatives are currently developing, one to invite and promote the use of environmental kinetics data (laboratory time course data) through ChemxSeer, and the other to invite and promote the use of spatially indexed geochemical data for the Earth's Critical Zone through CZEN.org. The vision of these CI initiatives is to provide cyber-enhanced portals that encourage domain scientists to upload their data before publication (in private cyberspace), and to make these data eventually publicly accessible (after an embargo period). If the CI can be made to provide services to the domain specialist - e.g. to provide data analysis services or data comparison services - we envision that scientists will upload data. In addition, the CI can promote the use and comparison of datasets across disciplines. For example, the CI can facilitate the use of spatially indexed geochemical data by scientists more accustomed to dealing with time-course data for hydrologic flow, and can provide user-friendly interfaces with CI established to facilitate the use of hydrologic data. Examples of the usage of synthesized data to predict soil development over the last 13ky and its effects on active hydrological flow boundaries in surficial systems will be discussed for i) a N-S loess climate transect; and ii) a shale catchment.

Brantley, S. L.; Kubicki, J.; Miller, D.; Richter, D.; Giles, L.; Mitra, P.

2007-12-01

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

Synthesizing plant phenological indicators from multispecies datasets  

Science.gov (United States)

Changes in the seasonality of life cycles of plants from phenological observations are traditionally analysed at the species level. Trends and correlations with main environmental driving variables show a coherent picture across the globe. The question arises whether there is an integrated phenological signal across species that describes common interannual variability. Is there a way to express synthetic phenological indicators from multispecies datasets that serve decision makers as usefull tools? Can these indicators be derived in such a robust way that systematic updates yield necessary information for adaptation measures? We address these questions by analysing multi-species phenological data sets with leaf-unfolding and flowering observations from 30 sites across Europe between 40° and 63°N including data from PEP725, the Swiss Plant Phenological Observation Network and one legacy data set. Starting in 1951 the data sets were synthesized by multivariate analysis (Principal Component Analysis). The representativeness of the site specific indicator was tested against subsets including only leaf-unfolding or flowering phases, and by a comparison with a 50% random sample of the available phenophases for 500 time steps. Results show that a synthetic indicators explains up to 79% of the variance at each site - usually 40-50% or more. Robust linear trends over the common period 1971-2000 indicate an overall change of the indicator of -0.32 days/year with lower uncertainty than previous studies. Advances were more pronounced in southern and northern Europe. The indicator-based analysis provides a promising tool for synthesizing site-based plant phenological records and is a companion to, and validating data for, an increasing number of phenological measurements derived from phenological models and satellite sensors.

Rutishauser, This; Peñuelas, Josep; Filella, Iolanda; Gehrig, Regula; Scherrer, Simon C.; Röthlisberger, Christian

2014-05-01

410

Porous oxides synthesized by the combustion method  

International Nuclear Information System (INIS)

The result of this work, seeks to be a contribution for the treatment of radioactive wastes, with base to the sorption properties that present those porous oxides, synthesized by a method that allows to increase the sorption capacity. The main objective of the present investigation has been the modification of the structural characteristics of the oxides of Fe, Mg and Zn to increase its capacity of sorption of 60 Co in particular. It was studied the effect of the synthesis method by combustion in the inorganic oxides; the obtained solids were characterized using the following techniques: X-ray diffraction (XRD), scanning electron microscopy (SEM), semiquantitative elementary analysis by Dispersive energy spectroscopy (EDS) and determination of surface area by the Brunauner-Emmett-Teller method (BET). Also was carried out batch type experiments for the sorption of Co2+, with the purpose of studying the sorption capacity of each one of the prepared oxides. In accordance with that previously exposed, the working plan that was carried out in this investigation is summarized in the following stages: 1. Preparation of inorganic oxides by two different methods, studying the effect of the temperature in the synthesis process. 2. Characterization of the inorganic oxides by XRD, by means of which those were chosen the solids with better properties. 3. Characterization of the inorganic oxides by SEM and EDS where it was studied the morphology of the synthesized materials and the semiquantitative elemental composition. 4. Realization of a sorption experiment type Batch with non radioactive Co2+ to simulate the sorption of 60 Co and determination of the sorption capacity by means of neutron activation of the non radioactive cobalt. 5. Determination of the surface area by the (BET) technique of the inorganic oxides with better sorption properties. (Author)

411

Phase behavior of multi-arm star-shaped polystyrene-block-poly(methyl methacrylate) copolymer  

Science.gov (United States)

We synthesized star-shaped polystyrene-block-poly(methyl methacrylate) copolymer (PS-b-PMMA) by utilizing ?-cyclodextrin (?-CD) as a core of the star-shaped block copolymer. Eighteen hydroxyl groups on ?-CD were transformed to bromine by the reaction with ?-bromoisobutyryl bromide. We found that the number of bromine substituted arms per one ?-CD was higher than 16, which was determined by nuclear magnetic resonance and Matrix-assisted laser desorption/ionization. We could control molecular weight of block copolymers by changing polymerization times. The block copolymers were characterized by gel permeation chromatography and nuclear magnetic resonance. Phase behaviors of these star-shaped block copolymers were investigated by small angle X-ray scattering and transmission electron microscopy.

Jang, Sangshin; Moon, Hong Chul; Bae, Dusik; Kwak, Jonghen; Kim, Jin Kon

2013-03-01

412

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

413

Kinematic feedback control laws for generating natural arm movements.  

Science.gov (United States)

We propose a stochastic optimal feedback control law for generating natural robot arm motions. Our approach, inspired by the minimum variance principle of Harris and Wolpert (1998 Nature 394 780-4) and the optimal feedback control principles put forth by Todorov and Jordan (2002 Nature Neurosci. 5 1226-35) for explaining human movements, differs in two crucial respects: (i) the endpoint variance is minimized in joint space rather than Cartesian hand space, and (ii) we ignore the dynamics and instead consider only the second-order differential kinematics. The feedback control law generating the motions can be straightforwardly obtained by backward integration of a set of ordinary differential equations; these equations are obtained exactly, without any linear-quadratic approximations. The only parameters to be determined a priori are the variance scale factors, and for both the two-DOF planar arm and the seven-DOF spatial arm, a table of values is constructed based on the given initial and final arm configurations; these values are determined via an optimal fitting procedure, and consistent with existing findings about neuromuscular motor noise levels of human arm muscles. Experiments conducted with a two-link planar arm and a seven-DOF spatial arm verify that the trajectories generated by our feedback control law closely resemble human arm motions, in the sense of producing nearly straight-line hand trajectories, having bell-shaped velocity profiles, and satisfying Fitts Law. PMID:24343165

Kim, Donghyun; Jang, Cheongjae; Park, Frank C

2014-03-01

414

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

415

Risk factors of arm lymphedema in breast cancer patients  

DEFF Research Database (Denmark)

Chronic lymphedema is a life-long, potential complication of axillary treatment for breast cancer patients. In this article we focus on risk factors in the development of arm lymphedema and also discuss definition, type and stage, and incidence of arm edema.

Kocak, Z; Overgaard, J

2000-01-01

416

Kinematic properties of supergiants in the Perseus spiral arm  

International Nuclear Information System (INIS)

Large-scale inhomogeneity of the velocity field in the Perseus spiral arm region is found on the basis of the analysis of spatial motions of supergiants. The inhomogeneity seems to be connected with both presence of large groups of young stars and systematic motions in the arm predicted by the density wave theory. Proper motions of 78 stars are presented

417

Scrape on Endeavour's robotic arm during oxygen leak repairs  

Science.gov (United States)

KENNEDY SPACE CENTER, FLA. -- Robotic arm experts begin inspection of a scrape on the surface of the honeycomb shell on Endeavour's robotic arm. The scrape occurred while work platforms were being installed to gain access to repair the oxygen leak in the Shuttle's mid-body. Launch of Endeavour on mission STS-113 has been postponed until no earlier than Nov. 22.

2002-01-01

418

Dynamic Coordination Of A Two-Arm Robotic Manipulator  

Science.gov (United States)

Report presents study of dynamical and kinematical considerations guiding selection of configuration of self-reconfigurable, two-arm robotic manipulator. Two multiple-link arms cooperate in manipulating single object, reconfiguring their mutual, cooperative structure according to changing task requirements.

Lee, Sukhan; Kim, Sungbok

1994-01-01

419

Robotic Arms. A Contribution to the Curriculum. An Occasional Paper.  

Science.gov (United States)

This report examines ways of providing technician training in the operating principles of robotic devices. The terms "robotics" and "robotic arms" are first defined. Some background information on the principal features of robotic arms is given, including their geometric arrangement, type of actuator used, control method, and software and teaching…

Arnold, W. F.; Carpenter, C. J.

420

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

421

Satellite data sets for the atmospheric radiation measurement (ARM) program  

Energy Technology Data Exchange (ETDEWEB)

This abstract describes the type of data obtained from satellite measurements in the Atmospheric Radiation Measurement (ARM) program. The data sets have been widely used by the ARM team to derive cloud-top altitude, cloud cover, snow and ice cover, surface temperature, water vapor, and wind, vertical profiles of temperature, and continuoous observations of weather needed to track and predict severe weather.

Shi, L.; Bernstein, R.L. [SeaSpace Corp., San Diego, CA (United States)

1996-04-01

422

ARMED FORCES AND INTERVENTION IN TROPICAL AFRICA  

Directory of Open Access Journals (Sweden)

Full Text Available "The Ghana Armed Forces, in co-operation with the police, have thought it necessary to take over the reins of power and to dismiss the former President, Kwame Nkrumah, the Presidential Commission and all Ministers, and to suspend the Constitution and to dissolve Parliament. This act has been necessitated by the political and economic situation in the country. The concentration of power in the hands of one man has led to the abuse of individual rights and liberty. Power has been exercised by the former President capriciously. The operation of the laws has been suspended to the advantage of his favourites and he has been running the country as his own personal property. "

L. Steyn

2012-02-01

423

VAST 2010 Challenge: Arms Dealings and Pandemics  

Energy Technology Data Exchange (ETDEWEB)

The 5th VAST Challenge consisted of three mini-challenges that involved both intelligence analysis and bioinformatics. Teams could solve one, two or all three mini-challenges and assess the overall situation to enter the Grand Challenge. Mini-challenge one involved text reports about people and events giving information about arms dealers, situations in various countries and linkages between different countries. Mini-challenge two involved hospital admission and death records from various countries providing information about the spread of a world wide pandemic. Mini-challenge three involved genetic data to be used to identify the origin of the pandemic and the most dangerous viral mutations. The Grand Challenge was to determine how these various mini-challenges were connected. As always the goal was to analyze the data and provide novel interactive visualizations useful in the analytic process. We received 58 submissions in total and gave 15 awards.

Grinstein, Georges; Konecni, Shawn; Plaisant, Catherine; Scholtz, Jean; Whiting, Mark A.

2010-10-23

424

Nonlinear dynamic analysis for elastic robotic arms  

Science.gov (United States)

The aim of the paper is to analyze the nonlinear dynamics of robotic arms with elastic links and joints. The main contribution of the paper is the comparative assessment of assumed modes and finite element methods as more convenient approaches for computing the nonlinear dynamic of robotic systems. Numerical simulations comprising both methods are carried out and results are discussed. Hence, advantages and disadvantages of each method are illustrated. Then, adding the joint flexibility to the system is dealt with and the obtained model is demonstrated. Finally, a brief description of the optimal motion generation is presented and the simulation is carried out to investigate the role of robot dynamic modeling in the control of robots.

Korayem, M. H.; Rahimi, H. N.

2011-06-01

425

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

426

'Great power' intervention in African armed conflicts  

DEFF Research Database (Denmark)

This paper asks why the United States (US), China and the European Union (EU) have intervened in a number of armed conflicts in Africa in the twenty-first century. Scrutiny and comparison of the motivations and interests of the three non-African actors in intervening in African crises are assumed to contribute to understanding the changing geopolitical environment and the current conditions for conflict management in Africa. The focus is not on trade and aid. The paper launches the hypothesis that the explanations why the US, China and the EU have intervened are basically identical. In spite of different evaluations of the specific crisis situations, the interventions have been about taking care of the ‘national interest’ of each of the three non-African actors. National interest is defined as either ‘hard core’ (security) or ‘core’ concerns (security and economic wealth).

Olsen, Gorm Rye

2015-01-01

427

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

428

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

429

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

430

Effect of Shim Arm Depletion in the NBSR  

Energy Technology Data Exchange (ETDEWEB)

The cadmium shim arms in the NBSR undergo burnup during reactor operation and hence, require periodic replacement. Presently, the shim arms are replaced after every 25 cycles to guarantee they can maintain sufficient shutdown margin. Two prior reports document the expected change in the 113Cd distribution because of the shim arm depletion. One set of calculations was for the present high-enriched uranium fuel and the other for the low-enriched uranium fuel when it was in the COMP7 configuration (7 inch fuel length vs. the present 11 inch length). The depleted 113Cd distributions calculated for these cores were applied to the current design for an equilibrium low-enriched uranium core. This report details the predicted effects, if any, of shim arm depletion on the shim arm worth, the shutdown margin, power distributions and kinetics parameters.

Hanson A. H.; Brown N.; Diamond, D.J.

2013-02-22

431

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

432

The dynamics of long-lived spiral arms  

Directory of Open Access Journals (Sweden)

Full Text Available It has been believed that spiral arms in pure stellar disks decay in several galactic rotations due to the heating by the spiral arms. However, it might be caused by a numerical heating. We performed a three-dimensional N-body simulations with a sufficiently large number of particles and found that stellar disks can maintain spiral arms for more than 10 Gyr without the help of cooling. Spiral arms are transient and recurrent and they heat disk with a heating rate, dQ/dt, correlated to the spiral amplitude |Am|. On the other hand, |Am| is suppressed by Toomre’s Q. Therefore, the dynamical heating becomes less effective in the later phase of the evolution. This mechanism maintain the spiral arms for more than 10 Gyr.

Wada K.

2012-02-01

433

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

434

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

435

The illusion of owning a third arm.  

Science.gov (United States)

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 by questionnaire data in conjunction with physiological evidence obtained from skin conductance responses when physically threatening either the rubber hand or the real one. In four well-controlled experiments, we demonstrate the minimal required conditions for the elicitation of this "supernumerary hand illusion". In the fifth, and final experiment, we show that the illusion reported here is qualitatively different from the traditional rubber hand illusion as it is characterised by less disownership of the real hand and a stronger feeling of having two right hands. These results suggest that the artificial hand 'borrows' some of the multisensory processes that represent the real hand, leading to duplication of touch and ownership of two right arms. This work represents a major advance because it challenges the traditional view of the gross morphology of the human body as a fundamental constraint on what we can come to experience as our physical self, by showing that the body representation can easily be updated to incorporate an additional limb. PMID:21383847

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

2011-01-01

436

Nuclear arms race gearing for speedup  

International Nuclear Information System (INIS)

To probe the rationale behind the big buildup in US strategic arms that is presaged by the current enhanced R and D effort - and to explore the broader, more long-term role of science and technology in the nuclear arms race - C and EN in recent months spoke with a host of experts both within and outside the defense establishment. It is a topic of incredible complexity, high controversy, and of the highest stakes imaginable - the survival of civilization. This buildup will include over the next decade, apart from the MX, a new, highly accurate, submarine-launched ballistic missile and a fleet of very large submarines to carry it; an air-launched cruise missile; a new long-range bomber; a new intermediate-range missile and a new ground-launched cruise missile, both capable of hitting targets in the Soviet Union from proposed bases in Western Europe; and a new sea-launched cruise missile that can be fired from conventional submarines or other naval vessels. To spokesmen for, and members of, the defense establishment the US buildup is prudent, even minimal. According to them, it is needed to keep the US at least on a par with the growth of Soviet strategic might which was very substantial in the 1970's and which will carry over into the 1980's with further major gains. It also is needed to keep the lid on Soviet expansionism; and it is the best way to prevent a nuclear war. To critics, the proposed buildup is the height of lunacy. According to them, the US strategic arsen According to them, the US strategic arsenal is more than adequate today. And it can continue to serve its only legitimate purpose - to deter nuclear war, no matter how much the Soviets may choose to build up their nuclear forces - with a much-more-modest modernization program

437

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

438

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

439

Anything But Arms? Perceptions, the European Union and the Arms Embargo on China  

Directory of Open Access Journals (Sweden)

Full Text Available This article examines the debate that emerged in the European Union (EU in late 2003 and ran to mid-2005 on the possibility of lifting the arms embargo imposed on the People’s Republic of China (PRC since June 1989. It seeks to offer a more nuanced explanation of the developments in the EU’s arms embargo policy towards China than has been put forward in the existing literature to date, which makes assumptions about the motivations of certain actors. To do so, it examines how the perceptions of key policymakers in the EU and two of its Member States – France and the United Kingdom (UK – influenced their positions in the debate. The article argues that an account focusing on the variation in perceptions between actors and consequently divergent policy preferences through close process-tracing of the development of the policy facilitates a more nuanced explanation of the proceedings of the debate.

Scott A. W. Brown

2011-02-01

440

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

441

49 CFR 1544.221 - Carriage of prisoners under the control of armed law enforcement officers.  

Science.gov (United States)

...prisoners under the control of armed law enforcement officers. 1544.221 Section...prisoners under the control of armed law enforcement officers. (a) This section...under the escort of an armed law enforcement officer. (2) This...

2010-10-01

442

49 CFR 236.531 - Trip arm; height and distance from rail.  

Science.gov (United States)

...4 2010-10-01 2010-10-01 false Trip arm; height and distance from rail. 236...Rules and Instructions; Roadway § 236.531 Trip arm; height and distance from rail. Trip arm of automatic train stop device when...

2010-10-01

443

48 CFR 552.237-72 - Prohibition Regarding “Quasi-Military Armed Forces.”  

Science.gov (United States)

...552.237-72 Prohibition Regarding “Quasi-Military Armed Forces.” As prescribed...following clause: Prohibition Regarding “Quasi-Military Armed Forces” (SEP 1999...term of this contract, offer for hire “Quasi-Military Armed Forces” within...

2010-10-01

444

ARM9Core: un emulador del procesador ARM9TDMI para PC  

OpenAIRE

El proyecto consiste en desarrollar el núcleo de un emulador para PC del microprocesador ARM9TDMI usado en sistemas empotrados, dispositivos portátiles, etc... Este proyecto está diseñado como una librería que se puede incorporar a una aplicación que necesite reproducir el comportamiento de un sistema basado en dicho procesador. Su diseño permite la integración de forma sencilla junto con otros módulos que emulen las distintas partes del sistema, y a su vez facilita...

Hidalgo Serrano, Sergio; Huerta Aranda, Alberto; San?udo Vacas, Daniel

2007-01-01

445

Exoskeleton to Rehabilitate Paralyzed Arm Based on Patient Healthy Arm Guidance  

OpenAIRE

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...

Jiajia Hu; Xinmin Xu; Weidong Liu

2013-01-01

446

Commentary: Utility of the O-Arm in spinal surgery  

Science.gov (United States)

Background: More studies report the intraoperative benefits vs. risks of utilizing the O-Arm in performing pedicle screw insertion in spinal surgery. Methods/Results: Several studies document the utility of CT-guided O-arm placement of pedicle/lateral mass screws. Singh et al. documented the efficacy of CT guided-O Arm placement of pedicle screws and lateral mass screws in the upper cervical spine.[4] Specifically, 10 patients with unstable hangman's fractures (ages 17-80) required 52 screws; C2 pedicle screws (20), C3 lateral mass screws (20), C4 lateral mass screws (12) and one C2 pedicle screw. Of these only 5% were misplaced, and none had new neuorlogical deficits. Kim et al. demonstrated the safety/efficacy of the CT/O-arm in minimally invasive spine surgery (MIS) (posterior percutaneous spinal fusions).[1] Of 290 pedicle screws, 280 (96.6%) were acceptably placed. Kotani et al. compared the placement of 222 pedicle screws (29 patients operated upon with CT-based navigation) vs. 416 screws (32 having surgery using O-arm-based navigation); postoperative CT studies confirmed the accuracy of screw placement, and no significant differences in the frequency of grade 2-3 perforations between the two groups. Nelson et al. analyzed the radiation exposure delivered to the operating room staff utilizing C-arm fluoroscopy (C-arm), portable X-ray (XR) radiography, and portable cone-beam computed tomography (O-arm); the surgeon and assistant were exposed to higher levels of scatter radiation from the C-arm, with a 7.7-fold increase in radiation exposure on the tube vs. detector sides.[3] Conclusion: There are several pros and a few cons (radiation dosage) for the use of the O-arm in spine surgery. PMID:25593769

Epstein, Nancy E.

2014-01-01

447

Characterisation of arm microvibration recorded on an accelerometer.  

Science.gov (United States)

Microvibration (MV) of the freely hanging and firmly supported lower arm was studied (n = 8) using two accelerometers, one located over muscle tissue (brachioradialis muscle) and one over bony tissue (processus styloideus). Measurements were made in the completely relaxed arm (REST), during arterial occlusion (CUFF) and during mild handgrip (GRIP), first with the arm relaxed and hanging beside the chair and then repeated with the arm supported in a special rest. At REST. ballistocardiac forces were identified as the driving mechanism for the regular MV pattern, whereas actions of local pulse waves (CUFF) could be excluded. During GRIP irregular MV, related to the contraction process, became superimposed on both signals. The MV at REST was sensitive to arm position. In the freely hanging state, when the arm was family coupled to the trunk, ballistocardiac body motion was present over bony tissue, producing a low damped 7-13 Hz resonant response over muscle tissue. In the supported state, the arm became isolated from body motions. Nevertheless, ballistocardiac forces reached the arm, producing smaller oscillatory responses over bone and muscle tissue. Regionally produced MV (GRIP) was not sensitive to arm position, but the spectrum content in the 7-13 Hz region was very similar to REST. From these results it would appear, that a low damped 7-13 Hz resonance process exists in relaxed muscle tissue, which physiologically becomes stimulated by cardiac and muscle forces. From the close relationship of the simultaneous MV waveforms in the supported arm, evidence for mechanical coupling between bone and muscle tissue is given. PMID:9088841

Gallasch, E; Kenner, T

1997-01-01

448

Methyltriethoxysilane: New precursor for synthesizing silica aerogels  

International Nuclear Information System (INIS)

Traditionally, silica aerogels are synthesized using three silicon alkoxides, namely, tetraethoxysilane (TEOS), tetramethoxysilane (TMOS) and methyltrimethoxysilane (MTMS) for various applications in science as well as in technology. Among all these precursors, only MTMS-based silica aerogels are inherently superhydrophobic with so far reported, the highest contact angle of 173 deg. In the present paper, we reported a new precursor, namely, methyltriethoxysilane (MTES) for synthesizing the silica aerogels having the novel properties as that of MTMS-based aerogels. The aerogels have been prepared using the MTES by two-stage acid-base catalyzed sol-gel process followed by supercritical drying. The solvent and catalysts used for the synthesis were methanol (MeOH), oxalic acid (C2H2O4) and ammonium hydroxide (NH4OH), respectively. The aerogels of different densities were obtained by varying the molar ratio of MeOH/MTES (S) from 6.45 to 19.35. In order to get good quality aerogels in terms of low density, high contact angle and less volume shrinkage, the oxalic acid (A) and NH4OH (B) concentrations were varied from 0 to 1 and from 2 to 13.36 M, respectively. Monolithic aerogels have been obtained for the values of A = 0.01 M and B = 13.36 M. Simultaneously, the aerogels are superhydrophobic with contact angle as high as 163 deg. Furthermore, the effects of molar ratio of H2O/MTES (W1), i.e. acidic water and 2O/MTES (W1), i.e. acidic water and H2O/MTES (W2), i.e. basic water on the physical properties of the aerogels have also been studied. The molar ratio of MTES:MeOH:acidic water:basic water was optimized at 1:19.35:3.57:3.57, respectively. The aerogel thermal stability was studied by TGA-DTA while the hydrophobicity was quantified in terms of the contact angle measurements and FTIR studies. The as-prepared aerogels have been characterized by bulk density, porosity, volume shrinkage, thermal conductivity, contact angle measurements, transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) spectroscopy. The physical properties of the aerogels have been explained by taking into account of sol-gel reactions and the gel network formation

449

Methyltriethoxysilane: New precursor for synthesizing silica aerogels  

Energy Technology Data Exchange (ETDEWEB)

Traditionally, silica aerogels are synthesized using three silicon alkoxides, namely, tetraethoxysilane (TEOS), tetramethoxysilane (TMOS) and methyltrimethoxysilane (MTMS) for various applications in science as well as in technology. Among all these precursors, only MTMS-based silica aerogels are inherently superhydrophobic with so far reported, the highest contact angle of 173 deg. In the present paper, we reported a new precursor, namely, methyltriethoxysilane (MTES) for synthesizing the silica aerogels having the novel properties as that of MTMS-based aerogels. The aerogels have been prepared using the MTES by two-stage acid-base catalyzed sol-gel process followed by supercritical drying. The solvent and catalysts used for the synthesis were methanol (MeOH), oxalic acid (C{sub 2}H{sub 2}O{sub 4}) and ammonium hydroxide (NH{su