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Sample records for one-dimensional coordination polymers

  1. Semiconductive and magnetic one-dimensional coordination polymers of Cu(II) with modified nucleobases.

    PubMed

    Amo-Ochoa, Pilar; Castillo, Oscar; Gómez-García, Carlos J; Hassanein, Khaled; Verma, Sandeep; Kumar, Jitendra; Zamora, Félix

    2013-10-01

    Four new copper(II) coordination complexes, obtained by reaction of CuX2 (X = acetate or chloride) with thymine-1-acetic acid and uracil-1-propionic acid as ligands, of formulas [Cu(TAcO)2(H2O)4]·4H2O (1), [Cu(TAcO)2(H2O)2]n (2), [Cu3(TAcO)4(H2O)2(OH)2]n·4H2O (3), and [Cu3(UPrO)2Cl2(OH)2(H2O)2]n (4) (TAcOH = thymine-1-acetic acid, UPrOH = uracil-1-propionic acid) are described. While 1 is a discrete complex, 2-4 are one-dimensional coordination polymers. Complexes 2-4 present dc conductivity values between 10(-6) and 10(-9) S/cm(-1). The magnetic behavior of complex 2 is typical for almost isolated Cu(II) metal centers. Moderate-weak antiferromagnetic interactions have been found in complex 3, whereas a combination of strong and weak antiferromagnetic interactions have been found in complex 4. Quantum computational calculations have been done to estimate the individual "J" magnetic coupling constant for each superexchange pathway in complexes 3 and 4. Compounds 2-4 are the first known examples of semiconductor and magnetic coordination polymers containing nucleobases. PMID:24040754

  2. Two different one-dimensional Cd(II) halide coordination polymers constructed through bridging carboxylate ligands.

    PubMed

    Hou, Xue Li; Wang, Hui Ting

    2015-11-01

    Two cadmium halide complexes, catena-poly[[chloridocadmium(II)]-di-?-chlorido-[chloridocadmium(II)]-bis[?2-4-(dimethylamino)pyridin-1-ium-1-acetate]-?(3)O:O,O';?(3)O,O':O], [CdCl2(C9H12N2O2)]n, (I), and catena-poly[1-cyanomethyl-1,4-diazoniabicyclo[2.2.2]octane [[dichloridocadmium(II)]-?-oxalato-?(4)O(1),O(2):O(1'),O(2')] monohydrate], {(C8H15N3)[CdCl2(C2O4)]·H2O}n, (II), were synthesized in aqueous solution. In (I), the Cd(II) cation is octahedrally coordinated by three O atoms from two carboxylate groups and by one terminal and two bridging chloride ligands. Neighbouring Cd(II) cations are linked together by chloride anions and bridging O atoms to form a one-dimensional zigzag chain. Hydrogen-bond interactions are involved in the formation of the two-dimensional network. In (II), each Cd(II) cation is octahedrally coordinated by four O atoms from two oxalic acid ligands and two terminal Cl(-) ligands. Neighbouring Cd(II) cations are linked together by oxalate groups to form a one-dimensional anionic chain, and the water molecules and organic cations are connected to this one-dimensional zigzag chain through hydrogen-bond interactions. PMID:26524171

  3. "Dual-template" synthesis of one-dimensional conductive nanoparticle superstructures from coordination metal-peptide polymer crystals.

    PubMed

    Rubio-Martínez, Marta; Puigmartí-Luis, Josep; Imaz, Inhar; Dittrich, Petra S; Maspoch, Daniel

    2013-12-20

    Bottom-up fabrication of self-assembled structures made of nanoparticles may lead to new materials, arrays and devices with great promise for myriad applications. Here a new class of metal-peptide scaffolds is reported: coordination polymer Ag(I)-DLL belt-like crystals, which enable the dual-template synthesis of more sophisticated nanoparticle superstructures. In these biorelated scaffolds, the self-assembly and recognition capacities of peptides and the selective reduction of Ag(I) ions to Ag are simultaneously exploited to control the growth and assembly of inorganic nanoparticles: first on their surfaces, and then inside the structures themselves. The templated internal Ag nanoparticles are well confined and closely packed, conditions that favour electrical conductivity in the superstructures. It is anticipated that these Ag(I)-DLL belts could be applied to create long (>100 ?m) conductive Ag@Ag nanoparticle superstructures and polymetallic, multifunctional Fe3 O4 @Ag nanoparticle composites that marry the magnetic and conductive properties of the two nanoparticle types. PMID:23828757

  4. A new one-dimensional coordination polymer of 5-(1,3-dioxo-4,5,6,7-tetraphenylisoindolin-2-yl)isophthalic acid with manganese.

    PubMed

    Wang, Jing; Jia, Chunmei; Feng, Xiao; Yuan, Wenbing

    2015-09-01

    The coordination polymer catena-poly[[(dimethylformamide-?O)[?3-5-(1,3-dioxo-4,5,6,7-tetraphenylisoindolin-2-yl)isophthalato-?(4)O(1),O(1'):O(3):O(3')](methanol-?O)manganese(III)] dimethylformamide monosolvate], {[Mn(C40H23NO6)(CH3OH)(C3H7NO)]·C3H7NO}n, has been synthesized from the reaction of 5-(1,3-dioxo-4,5,6,7-tetraphenylisoindolin-2-yl)isophthalic acid and manganese(II) acetate tetrahydrate in a glass tube at room temperature by solvent diffusion. The Mn(II) centre is hexacoordinated by two O atoms from one chelating carboxylate group, by two O atoms from two monodentate carboxylate groups and by one O atom each from a methanol and a dimethylformamide (DMF) ligand. The single-crystal structure crystallizes in the triclinic space group P\\overline{1}. Moreover, the coordination polymer shows one-dimensional 2-connected {0} uninodal chain networks, and free DMF molecules are connected to the chains by O-H···O hydrogen bonds. The thermogravimetric and photoluminescent properties of the compound have also been investigated. PMID:26322606

  5. One-dimensional transport in polymer nanofibers

    E-print Network

    A. N. Aleshin; H. J. Lee; Y. W. Park; K. Akagi

    2004-10-08

    We report our transport studies in quasi one-dimensional (1D) conductors - helical polyacetylene fibers doped with iodine and the data analysis for other polymer single fibers and tubes. We found that at 30 K < T < 300 K the conductance and the current-voltage characteristics follow the power law: G(T) ~ T^alpha with alpha ~ 2.2-7.2 and I(V) ~ V^betta with betta ~ 2-5.7. Both G(T) and I(V) show the features characteristic of 1D systems such as Luttinger liquid or Wigner crystal. The relationship between our results and theories for tunneling in 1D systems is discussed.

  6. A novel one-dimensional manganese(II) coordination polymer containing both dicyanamide and pyrazinamide ligands: Synthesis, spectroscopic investigations, X-ray studies and evaluation of biological activities

    NASA Astrophysics Data System (ADS)

    Tabrizi, Leila; Chiniforoshan, Hossein; McArdle, Patrick

    2015-03-01

    A novel 1D coordination polymer {[Mn(?1,5-dca)2(PZA)2](PZA)2}n, 1, has been synthesized and characterized by single crystal X-ray crystallography. The coordination mode of dicyanamide (dca) and pyrazinamide (PZA) ligands was inferred by IR spectroscopy. The compound 1 was evaluated for in vitro antimycobacterial and antitumor activities. It demonstrated better in vitro activity against Mycobacterium tuberculosis than pyrazinamide and its MIC value was determined. Complex 1 was also screened for its in vitro antitumor activity towards LM3 and LP07 murine cancer cell lines. In addition, the antibacterial activity of complex 1 has been tested against Gram(+) and Gram(-) bacteria and it has shown promising broad range anti-bacterial activity.

  7. Syntheses and Characterization of New Nickel Coordination Polymers with 4,4?-Dipyridylsulfide. Dynamic Rearrangements of One-Dimensional Chains Responding to External Stimuli: Temperature Variation and Guest Releases/Re-Inclusions

    PubMed Central

    Kondo, Mitsuru; Takahashi, Hideaki; Watanabe, Hirotaka; Shimizu, Yusuke; Yamanishi, Katsunori; Miyazawa, Makoto; Nishina, Naoko; Ishida, Yutaka; Kawaguchi, Hiroyuki; Uchida, Fumio

    2010-01-01

    Crystal structures and dynamic rearrangements of one-dimensional coordination polymers with 4,4?-dipyridylsulfide (dps) have been studied. Reaction of Ni(NO3)2·6H2O with dps in EtOH yielded [Ni(dps)2(NO3)2] ·EtOH (1), which had channels filled with guest EtOH molecules among the four Ni(dps)2 chains. This coordination polymer reversibly transformed the channel structure responding to temperature variations. Immersion of 1 in m-xylene released guest EtOH molecules to yield a guest-free coordination polymer [Ni(dps)2(NO3)2] (2a), which was also obtained by treatment of Ni(NO3)2·6H2O with dps in MeOH. On the other hand, removal of the guest molecules from 1 upon heating at 130 °C under reduced pressure produced a guest-free coordination polymer [Ni(dps)2(NO3)2] (2b). Although the 2a and 2b guest-free coordination polymers have the same formula, they showed differences in the assembled structures of the one-dimensional chains. Exposure of 2b to EtOH vapor reproduced 1, while 2a did not convert to 1 in a similar reaction. Reaction of Ni(NO3)2·6H2O with dps in acetone provided [Ni(dps)(NO3)2(H2O)] ·Me2CO (4) with no channel structure. When MeOH or acetone was used as a reaction solvent, the [Ni(dps)2(NO3)2] · (guest molecule) type coordination polymer, which was observed in 1, was not formed. Nevertheless, the reaction of Ni(NO3)2·6H2O with dps in MeOH/acetone mixed solution produced [Ni(dps)2(NO3)2]·0.5(MeOH·acetone) (5), which has an isostructural Ni-dps framework to 1. PMID:21152276

  8. A new one-dimensional Zn(II) coordination polymer based on 2-[(1H-imidazol-1-yl)methyl]-1H-benzimidazole and benzene-1,2-dicarboxylate.

    PubMed

    Huang, Qiu Ying; Liu, Wei; Yang, Yi; Meng, Xiang Ru

    2015-11-01

    Multidentate N-heterocyclic compounds form a variety of metal complexes with many intriguing structures and interesting properties. The title coordination polymer, catena-poly[zinc(II)-bis{?-2-[(1H-imidazol-1-yl)methyl]-1H-benzimidazole}-?(2)N(3):N(3');N(3'):N(3)-zinc(II)-bis(?-benzene-1,2-dicarboxylato)-?(2)O(1):O(2);?(3)O(1),O(1'):O(2)], [Zn2(C8H4O4)2(C11H10N4)2]n, has been synthesized by the reaction of Zn(NO3)2 with 2-[(1H-imidazol-1-yl)methyl]-1H-benzimidazole (imb) and benzene-1,2-dicarboxylic acid (H2bdic) under hydrothermal conditions. There are two crystallographically distinct imb ligands [imb(A) and imb(B)] in the structure which adopt very similar coordination geometries. The imb(A) ligand bridges two symmetry-related Zn1 ions, yielding a binuclear [(Zn1)2{imb(A)}2] unit, and the imb(B) ligand bridges two symmetry-related Zn2 ions resulting in a binuclear [(Zn2)2{imb(B)}2] unit. The above-mentioned binuclear units are further connected alternately by pairs of bridging bdic(2-) ligands, forming an infinite one-dimensional chain. These one-dimensional chains are further connected through N-H...O hydrogen bonds, leading to a two-dimensional layered structure. In addition, the title polymer exhibits good fluorescence properties in the solid state at room temperature. PMID:26524177

  9. One-dimensional mercury(II) halide coordination polymers of 3,6-bis(2-pyridyl)-1,2,4,5-tetrazine ligand: Synthesis, crystal structure, spectroscopic and DFT studies

    NASA Astrophysics Data System (ADS)

    Saghatforoush, Lotfali; Khoshtarkib, Zeinab; Amani, Vahid; Bakhtiari, Akbar; Hakimi, Mohammad; Keypour, Hassan

    2016-01-01

    Three new coordination polymers, [Hg(?-bptz)X2]n (X=Cl (1), Br (2)) and [Hg2(?-bptz)(?-I)2I2]n (3) (bptz=3,6-bis(2-pyridyl)-1,2,4,5-tetrazine) were synthesized. X-ray structural analysis indicated that compounds 1 and 2 are composed of one-dimensional (1D) linear chains while the compound 3 has 1D stair-stepped structure. The electronic band structure along with density of states (DOS) calculated by the DFT method indicates that compound 1 and 2 are direct band gap semiconductors; however, compound 3 is an indirect semiconductor. The linear optical properties of the compounds are also calculated by DFT method. According to the DFT calculations, the observed emission band of the compounds in solid state is due to electron transfer from an excited bptz-?* state (CBs) to the top of VBs. 1H NMR spectra of the compounds indicate that, in solution phase, the compounds don't decompose completely. Thermal stability of the compounds is studied using TG, DTA methods.

  10. A meso-one-dimensional coordination polymer based on racemic 2-(1-oxo-1 H-2,3-dihydroisoindol-2-yl)benzoic acid: Synthesis, structure and properties

    NASA Astrophysics Data System (ADS)

    Li, Hui; Chen, Yun; Ying, Shao-Ming; Zhang, Jian; Liu, Hui

    2009-11-01

    A novel polymeric complex NaCo( o-pba) 3(H 2O) 3 ( o-Hpba = 2-(1-oxo-1 H-2,3-dihydroisoindol-2-yl)benzonic acid) based on racemic N-arylphthalimidine ligand has been prepared and characterized by elemental analysis, spectroscopic and X-ray crystallography methods. In the compound, each Co(II) cation is coordinated by six O atoms from three carboxyl groups of o-pba - and three water molecules in fac-MA 3B 3 model forming a chiral tripodal Co( o-pba) 3(H 2O) 3- anion-complex, enantiomeric pairs of which are alternately arranged in head-to-head and tail-to-tail orientations giving rise to a meso-one-dimensional chain-like structure. The compound exhibits high stability and unusual triple-peak luminescence in DMSO solution at room temperature.

  11. Luminescent lanthanide coordination polymers

    SciTech Connect

    Ma, L.; Evans, O.R.; Foxman, B.M.; Lin, W.

    1999-12-13

    One-dimensional lanthanide coordination polymers with the formula Ln(isonicotinate){sub 3}(H{sub 2}O){sub 2} (Ln = Ce, Pr, Nd, Sm, Eu, Tb; 1a-f) were synthesized by treating nitrate or perchlorate salts of Ln(III) with 4-pyridinecarboxaldehyde under hydro(solvo)thermal conditions. Single-crystal and powder X-ray diffraction studies indicate that these lanthanide coordination polymers adopt two different structures. While Ce(III), Pr(III), and Nd(III) complexes adopt a chain structure with alternating Ln-(carboxylate){sub 2}-Ln and Ln-(carboxylate){sub 4}-Ln linkages, Sm(III), Eu(III), and Tb(III) complexes have a doubly carboxylate-bridged infinite-chain structure with one chelating carboxylate group on each metal center. In both structures, the lanthanide centers also bind to two water molecules to yield an eight-coordinate, square antiprismatic geometry. The pyridine nitrogen atoms of the isonicotinate groups do not coordinate to the metal centers in these lanthanide(III) complexes; instead, they direct the formation of Ln(III) coordination polymers via hydrogen bonding with coordinated water molecules. Photoluminescence measurements show that Tb(isonicotinate){sub 3}(H{sub 2}O){sub 2} is highly emissive at room temperature with a quantum yield of {approximately}90%. These results indicate that highly luminescent lanthanide coordination polymers can be assembled using a combination of coordination and hydrogen bonds. Crystal data for 1a: monoclinic space group P2{sub 1}/c, a = 9.712(2) {angstrom}, b = 19.833(4) {angstrom}, c = 11.616(2) {angstrom}, {beta} = 111.89(3){degree}, Z = 4. Crystal data for 1f: monoclinic space group C2/c, a = 20.253(4) {angstrom}, b = 11.584(2) {angstrom}, c = 9.839(2) {angstrom}, {beta} = 115.64(3){degree}, Z = 8.

  12. Two-time distribution function in one-dimensional random directed polymers

    NASA Astrophysics Data System (ADS)

    Dotsenko, Victor

    2015-12-01

    The explicit expression for the two-time free energy distribution function in one-dimensional random directed polymers is derived in terms of the Bethe ansatz replica technique. It is shown that such type of the distribution function can be represented in the form of a generalized ‘two-dimensional’ Fredholm determinant.

  13. Improving brush polymer infrared one-dimensional photonic crystals via linear polymer additives.

    PubMed

    Macfarlane, Robert J; Kim, Bongkeun; Lee, Byeongdu; Weitekamp, Raymond A; Bates, Christopher M; Lee, Siu Fung; Chang, Alice B; Delaney, Kris T; Fredrickson, Glenn H; Atwater, Harry A; Grubbs, Robert H

    2014-12-17

    Brush block copolymers (BBCPs) enable the rapid fabrication of self-assembled one-dimensional photonic crystals with photonic band gaps that are tunable in the UV-vis-IR, where the peak wavelength of reflection scales with the molecular weight of the BBCPs. Due to the difficulty in synthesizing very large BBCPs, the fidelity of the assembled lamellar nanostructures drastically erodes as the domains become large enough to reflect IR light, severely limiting their performance as optical filters. To overcome this challenge, short linear homopolymers are used to swell the arrays to ?180% of the initial domain spacing, allowing for photonic band gaps up to ?1410 nm without significant opacity in the visible, demonstrating improved ordering of the arrays. Additionally, blending BBCPs with random copolymers enables functional groups to be incorporated into the BBCP array without attaching them directly to the BBCPs. The addition of short linear polymers to the BBCP arrays thus offers a facile means of improving the self-assembly and optical properties of these materials, as well as adding a route to achieving films with greater functionality and tailorability, without the need to develop or optimize the processing conditions for each new brush polymer synthesized. PMID:25373000

  14. Polymer-loaded propagating modes on a one-dimensional photonic crystal

    SciTech Connect

    Han, Lu; Zhang, Douguo Chen, Yikai; Wang, Ruxue; Zhu, Liangfu; Wang, Pei; Ming, Hai; Lakowicz, Joseph R.; Badugu, Ramachandram

    2014-02-10

    We numerically and experimentally demonstrate that a polymer film-coated one-dimensional photonic crystal (1DPC) can sustain transverse electric (TE) polarized modes without the limit of guided layer's thickness. Our results indicate that two propagating modes are existing inside the polymer film, the first one is the TE polarized Bloch surface wave, and the second one is the TE polarized guided mode. Here in, the evolution of these two modes with change in the polymer film thickness is presented. Our numerical simulation results are in well-agreement with the experimental data obtained using back focal plane imaging.

  15. Fluorescence excitation enhancement by Bloch surface wave in all-polymer one-dimensional photonic structure

    SciTech Connect

    Fornasari, L.; Floris, F.; Patrini, M.; Guizzetti, G.; Marabelli, F.; Canazza, G.; Comoretto, D.

    2014-08-04

    We demonstrate photoluminescence excitation enhancement in an all-polymer flexible one-dimensional photonic crystal structure capped with a fluorescent organic ultrathin film. When optical matching conditions between the excitation beam and the Bloch Surface Wave mode supported by the photonic structure are achieved, a ten times enhancement of the photoluminescence is observed. We notice that in these systems luminescence signal reinforcement is achieved by increasing the pump efficiency with no need of spectral resonance to the emission of the chosen fluorophore. All these features make these systems suitable candidates for easy, flexible, and cheap fluorescent sensing.

  16. Pseudo one-dimensional analysis of polymer electrolyte fuel cell cold-start

    SciTech Connect

    Mukherjee, Partha P; Mukundan, Rangachary; Borup, Rodney L; Wang, Yun; Mishlera, Jeff

    2009-01-01

    This paper investigates the electrochemical kinetics, oxygen transport, and solid water formation in polymer electrolyte fuel cell (PEFC) during cold start. Following [Yo Wang, J. Electrochem. Soc., 154 (2007) B1041-B1048], we develop a pseudo one-dimensional analysis, which enables the evaluation of the impact of ice volume fraction and temperature variations on cell performance during cold-start. The oxygen profile, starvation ice volume fraction, and relevant overpotentials are obtained. This study is valuable for studying the characteristics of PEFC cold-start.

  17. Coulomb-blockade transport in quasi-one dimensional polymer nanofibers

    E-print Network

    A. N. Aleshin; H. J. Lee; S. H. Jhang; H. S. Kim; K. Akagi; Y. W. Park

    2005-07-22

    We report the low temperature current-voltage (I-V) characteristics studies in quasi-one dimensional conducting polymer nanofibers. We find a threshold voltage Vt below which little current flows at temperatures below 30-40 K. For V > Vt current scales as (V/Vt - 1)^zeta, where zeta ~ 1.8-2.1 at high biases. Differential conductance oscillations are found whose magnitude increases as temperature decreases below 10 K. We attribute the observed low temperature I-V behavior to Coulomb blockade effects with a crossover to Luttinger liquid-like behavior at high temperature. We demonstrate that at low temperatures such a doped conjugated polymer fiber can be considered as an array of small conducting regions separated by nanoscale barriers, where the Coulomb blockade tunneling is the dominant transport mechanism.

  18. Relaxation dynamics of the one-dimensional Bose gas via the coordinate Bethe ansatz

    NASA Astrophysics Data System (ADS)

    Davis, Matthew; Zill, Jan; Wright, Tod; Kheruntsyan, Karen; Gasenzer, Thomas

    2015-05-01

    Recently there has been significant progress in understanding the nature of relaxation in closed quantum systems following a disturbance. Many of the theoretical results have been obtained through the study of models that can be mapped to non-interacting systems, or via approximate numerical methods. We instead utilise the symbolic evaluation of matrix elements between the coordinate Bethe-ansatz eigenstates of the Lieb-Liniger model to simulate quenches of the one-dimensional Bose gas for up to N = 5 particles. We consider a range of scenarios, including quenches of the interaction strength to both repulsive and attractive values, and the application of momentum kicks in analogy to the quantum Newton's cradle experiment of Ref.. Our approach allows us to compare the time-evolving nonequilibrium correlation functions to their diagonal-ensemble (infinite-time-average) values. We find evidence of relaxation to the diagonal ensemble following a quench to repulsive interactions, and most of our results for relaxed-state correlations agree with recent generalized thermodynamic Bethe-ansatz calculations. However, our results for local third-order correlations differ markedly from the predictions of these generalized ensembles.

  19. Kinetic analysis of quasi-one-dimensional growth of polymer lamellar crystals in dilute solutions.

    PubMed

    Zhou, Yujie; Hu, Wenbing

    2013-03-14

    Flexible polymers are featured with two-dimensional growth of metastable chain-folded lamellar crystals in quiescent dilute solutions. Recently, a massive cylindrical micelle with quasi-one-dimensional (quasi-1D) growth driven by confined crystallization of diblock copolymers in dilute solutions raised a new challenge. We performed dynamic Monte Carlo simulations to investigate the kinetics of quasi-1D growth of lamellar crystals in two typical cases of dilute but not very dilute polymer solutions. We found that in both cases the growth kinetics is dominated by the surface-nucleation-controlled mechanism. Moreover, in the first case corresponding to few and small crystals grown under almost constant polymer concentrations in the huge bulk of solutions, the driving-force term in the kinetic equation dominates a linear concentration dependence of crystal growth rates in the high-concentration region, and the nucleation-barrier term dominates their nonlinear deviation in the low-concentration region. In the second case corresponding to massive crystals grown under depleting polymer concentrations in a limited volume of solutions, the crystal growth rates decay with time, but at the early stage, they follow exactly with the linear-concentration-dependent growth rates of the first case. Therefore, the growth size at the early stage of the second case can be described as an exponential-decay function of time, which provides a theoretical model to the data analysis of corresponding experimental observations. PMID:23419206

  20. DOI: 10.1002/chem.200601174 Hydrogencyanamide-Bridged One-Dimensional Polymers Built on

    E-print Network

    Gao, Song

    to prepare a number of alkali metal,[2] alkaline-earth metal,[3] and rare-earth metal[4] salts by different, Prof. Dr. S. Gao Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth-Ming Wang, and Song Gao*[a] Introduction The design and synthesis of transition-metal coordination polymers

  1. An Angular Leakage Correction for Modeling a Hemisphere, Using One-Dimensional Spherical Coordinates

    SciTech Connect

    Schwinkendorf, K.N.; Eberle, C.S.

    2003-01-15

    A radially dependent, angular leakage correction was applied to a one-dimensional, multigroup neutron diffusion theory computer code to accurately model hemispherical geometry. This method allows the analyst to model hemispherical geometry, important in nuclear criticality safety analyses, with one-dimensional computer codes, which execute very quickly. Rapid turnaround times for scoping studies thus may be realized. This method uses an approach analogous to an axial leakage correction in a one-dimensional cylinder calculation. The two-dimensional Laplace operator was preserved in spherical geometry using a leakage correction proportional to 1/r{sup 2}, which was folded into the one-dimensional spherical calculation on a mesh-by-mesh basis. Hemispherical geometry is of interest to criticality safety because of its similarity to piles of spilled fissile material and accumulations of fissile material in process containers. A hemisphere also provides a more realistic calculational model for spilled fissile material than does a sphere.

  2. Determining the response of infinite, one-dimensional, non-uniform periodic structures by substructuring using waveshape coordinates

    NASA Astrophysics Data System (ADS)

    Brown, G. P.; Byrne, K. P.

    2005-10-01

    A method is presented for determining the wavenumbers, waveshapes and point receptances for an infinite, one-dimensional, non-uniform periodic structure with distributed periodic attachments or supports. The approach is based on a general theory of harmonic wave propagation in one-dimensional periodic systems. Ill-conditioning was previously reported as an impediment to applying the theory to problems of practical importance. In this paper ill-conditioning problems are overcome and a method of substructuring using waveshape coordinates is presented that dramatically improves computational efficiency. The accuracy and generality of the new method are tested by comparing computed and measured receptances for a typical TGV railway track with UIC60 rail, rail pad, ballast and concrete sleepers. The computed results are found to correlate well with measured data.

  3. Giant coercivity in a one-dimensional cobalt-radical coordination magnet.

    PubMed

    Ishii, Norio; Okamura, Yoshitomo; Chiba, Susumu; Nogami, Takashi; Ishida, Takayuki

    2008-01-01

    A metal-radical polymer [Co(hfac)2.BPNN] showed a very large coercive field of 52 kOe (4.1 MA m-1) at 6 K, indicating that it is the hardest magnet ever reported. Above 10 K, a soft character appeared, owing to the fast dynamics of magnetization reorientation. PMID:18076178

  4. Scaling for a one-dimensional directed polymer with boundary conditions

    E-print Network

    Timo Seppäläinen

    2015-08-26

    We study a (1+1)-dimensional directed polymer in a random environment on the integer lattice with log-gamma distributed weights. Among directed polymers, this model is special in the same way as the last-passage percolation model with exponential or geometric weights is special among growth models, namely, both permit explicit calculations. With appropriate boundary conditions, the polymer with log-gamma weights satisfies an analogue of Burke's theorem for queues. Building on this, we prove the conjectured values for the fluctuation exponents of the free energy and the polymer path, in the case where the boundary conditions are present and both endpoints of the polymer path are fixed. For the polymer without boundary conditions and with either fixed or free endpoint, we get the expected upper bounds on the exponents.

  5. Fabrication and mechanical properties of suspended one-dimensional polymer nanostructures: polypyrrole nanotube and helical polyacetylene nanofibre

    NASA Astrophysics Data System (ADS)

    Lee, S. W.; Kim, B.; Lee, D. S.; Lee, H. J.; Park, J. G.; Ahn, S. J.; Campbell, E. E. B.; Park, Y. W.

    2006-02-01

    Mechanical properties of suspended quasi-one-dimensional polymer nanostructures were investigated using atomic force microscopy (AFM). A recently developed new acid-free etch method combined with electron beam lithography was used to fabricate suspended polypyrrole (PPy) nanotubes and helical polyacetylene (HPA) nanofibres. The elastic modulus of each suspended structure was obtained by AFM force-distance measurements. The estimated modulus value of the PPy nanotube (HPA nanofibre) was 0.96 GPa (0.5 GPa). Using this acid-free method, all-organic flexible NEMS devices can be fabricated in the future.

  6. Controlled assembly of graphene oxide nanosheets within one-dimensional polymer nanostructure.

    PubMed

    Park, Ho Seok; Choi, Bong Gill; Hong, Won Hi; Jang, Sung-Yeon

    2013-09-15

    We have demonstrated that the location and distribution of graphene oxide nanosheets (GONs) confined in 1D polymer composites were readily controlled depending on the processing conditions of electrospinning such as the types of polymers and the solvents used for the fabrication. The uniform bead-free poly(vinyl alcohol) (PVA)/GON composite nanofibers (NFs) even at high GON loading were obtained from the homogeneous polymer solutions attributable to the favorable interactions, as elucidated by spectroscopic data, thereby showing significant enhancement of their physical properties. The GONs were localized in the surface regions of the PVA-NFs due to the rapid convective evaporation of the water molecules, with concomitant aggregation into several sheets (<10 layers). In contrast, the co-continuous internal morphology of PVA/GON-NFs was constructed using less-volatile, polar dimethylformamide (DMF) solvents. Furthermore, the GONs were uniformly distributed in the more compatible polymer matrices such as polyacrylonitrile (PAN) and polystyrene (PS). Therefore, the distribution of GONs in 1D nanofibers was governed by the kinetics of solvent evaporation and the interaction with the polymer matrices. PMID:23810546

  7. The scaling limit of polymer pinning dynamics and a one dimensional Stefan freezing problem

    E-print Network

    Hubert Lacoin

    2013-04-26

    We consider the stochastic evolution of a 1+1-dimensional interface (or polymer) in presence of a substrate. This stochastic process is a dynamical version of the homogeneous pinning model. We start from a configuration far from equilibrium: a polymer with a non-trivial macroscopic height profile, and look at the evolution of a space-time rescaled interface. In two cases, we prove that this rescaled interface has a scaling limit on the diffusive scale (space rescaled by $L$ in both dimensions and time rescaled by $L^2$ where $L$ denotes the length of the interface) which we describe: when the interaction with the substrate is such that the system is unpinned at equilibrium, then the scaling limit of the height profile is given by the solution of the heat equation with Dirichlet boundary condition ; when the attraction to the substrate is infinite, the scaling limit is given a free-boundary problem which belongs to the class of Stefan problems with contracting boundary, also referred to as Stefan freezing problems. In addition, we prove the existence and regularity of the solution to this problem until a maximal time, where the boundaries collide.

  8. A coordinate Bethe ansatz approach to the calculation of equilibrium and nonequilibrium correlations of the one-dimensional Bose gas

    E-print Network

    Zill, J C; Kheruntsyan, K V; Gasenzer, T; Davis, M J

    2016-01-01

    We use the coordinate Bethe ansatz to exactly calculate matrix elements between eigenstates of the Lieb-Liniger model of one-dimensional bosons interacting via a two-body delta-potential. We investigate the static correlation functions of the zero-temperature ground state and their dependence on interaction strength, and analyze the effects of system size in the crossover from few-body to mesoscopic regimes for up to seven particles. We also obtain time-dependent nonequilibrium correlation functions for five particles following quenches of the interaction strength from two distinct initial states. One quench is from the non-interacting ground state and the other from a correlated ground state near the strongly interacting Tonks-Girardeau regime. The final interaction strength and conserved energy are chosen to be the same for both quenches. The integrability of the model highly constrains its dynamics, and we demonstrate that the time-averaged correlation functions following quenches from these two distinct i...

  9. Porphyrin coordination polymer nanospheres and nanorods

    SciTech Connect

    Wang, Zhongchun; Shelnutt, John A.; Medforth, Craig J.

    2012-12-04

    A porphyrin coordination polymer nanostructure comprising a network of pyridyl porphyrin molecules and coordinating metal ions coordinatively bound through the pyridyl groups. In some embodiments, the porphyrins are metalloporphyrins. A variety of nanostructures are formed by the network polymer, including nanospheres, polygonal nanostructures, nanorods, and nanofibers, depending on a variety of factors including coordination metal ion, porphyrin type, metal of the metalloporphyrin, and degree of agitation during nanostructure formation. Reduction of coordinating metal ions may be used to form metal nanoparticles on the coordination polymer nanostructure.

  10. Anomaly in the electric resistivity of one-dimensional uneven peanut-shaped C60 polymer film at a low temperature

    NASA Astrophysics Data System (ADS)

    Ryuzaki, Soh; Onoe, Jun

    2014-03-01

    We performed in situ four-probe measurements of the current-voltage characteristics of one-dimensional (1D) uneven peanut-shaped C60 polymer films in the temperature range 30-350 K under ultrahigh vacuum conditions (2 × 10-7 Pa). Arrhenius plots of the film resistance with respect to temperature showed two different electron-conduction mechanisms. While electrons are conducted via a thermal excitation hopping at temperatures above 160 K, the resistivity of the 1D polymer film exhibits an anomalous behavior that becomes fluctuated at a given value in the temperature range 40-90 K and decreases at temperatures below 40 K.

  11. Anomaly in the electric resistivity of one-dimensional uneven peanut-shaped C{sub 60} polymer film at a low temperature

    SciTech Connect

    Ryuzaki, Soh; Onoe, Jun

    2014-03-17

    We performed in situ four-probe measurements of the current-voltage characteristics of one-dimensional (1D) uneven peanut-shaped C{sub 60} polymer films in the temperature range 30–350?K under ultrahigh vacuum conditions (2?×?10{sup ?7}?Pa). Arrhenius plots of the film resistance with respect to temperature showed two different electron-conduction mechanisms. While electrons are conducted via a thermal excitation hopping at temperatures above 160?K, the resistivity of the 1D polymer film exhibits an anomalous behavior that becomes fluctuated at a given value in the temperature range 40–90?K and decreases at temperatures below 40?K.

  12. 1D Zigzag Coordination Polymers of Copper(II) and Nickel(II) with Mixed Ligands Syntheses and Structures

    E-print Network

    Paik Suh, Myunghyun

    FULL PAPER 1D Zigzag Coordination Polymers of Copper(II) and Nickel(II) with Mixed Ligands Paik Suh*[a] Keywords: Magnetic properties / N ligands / Polymers / Copper / Nickel / Self assembly The one-dimensional coordination polymers [Cu(NO3)2(2,2 - bipy)(4,4 -bipy)]n·2nCH3OH (1) and [Ni(tren)(4

  13. Adsorption Kinetics in Nanoscale Porous Coordination Polymers.

    PubMed

    Nune, Satish K; Thallapally, Praveen K; McGrail, Benard Peter; Annapureddy, Harsha V R; Dang, Liem X; Mei, Donghai; Karri, Naveen; Alvine, Kyle J; Olszta, Matthew J; Arey, Bruce W; Dohnalkova, Alice

    2015-10-01

    Nanoscale porous coordination polymers were synthesized using simple wet chemical method. The effect of various polymer surfactants on colloidal stability and shape selectivity was investigated. Our results suggest that the nanoparticles exhibited significantly improved adsorption kinetics compared to bulk crystals due to decreased diffusion path lengths and preferred crystal plane interaction. PMID:26333118

  14. In situ infrared spectroscopic and density-functional studies of the cross-linked structure of one-dimensional C{sub 60} polymer

    SciTech Connect

    Takashima, A.; Onoe, J.; Nishii, T.

    2010-08-15

    We have examined the infrared (IR) spectra of electron-beam (EB) irradiated C{sub 60} films, using in situ IR spectroscopy in the temperature range of 60-300 K. The irradiation-time evolution of the IR spectra shows that two highly intense new peaks finally appear around 565 and 1340 cm{sup -1} when the EB-induced C{sub 60} polymerization was saturated. To determine the cross-linked structure of the polymer explicitly, we have compared the IR spectra with theoretical spectra obtained from the cross-linked structure of all C{sub 120} stable isomers derived from the general Stone-Wales (GSW) rearrangement, using first-principles density-functional calculations. Since each C{sub 120} isomer has the same cross-linked structure as that of its corresponding one-dimensional (1D) C{sub 60} polymer, the IR modes obtained from the cross-linked structure of C{sub 120} are close to those obtained from the corresponding 1D polymer. Comparison between the experimental and theoretical IR spectra suggests that the 1D peanut-shaped C{sub 60} polymer has a cross-linked structure roughly similar to that of the P08 peanut-shaped C{sub 120} isomer.

  15. Design of one-dimensional coordination networks from a macrocyclic {3d-4f} single-molecule magnet precursor linked by [W(CN)8]3- anions.

    PubMed

    Dhers, Sébastien; Feltham, Humphrey L C; Clérac, Rodolphe; Brooker, Sally

    2013-12-01

    The outcome of 1:1 reactions of the tetranuclear 3d-4f Single Molecule Magnet (SMM) [Cu3Tb(L(Pr))(NO3)2(H2O)]NO3 (1) with (TBA)3[W(CN)8] (TBA = tri-n-butyl ammonium cation, [(n-Bu)3N-H](+)) in dimethylformamide (DMF) is dependent on the crystallization method employed: liquid-liquid diffusion of the reagents together gives {[Cu3Tb(L(Pr))W(CN)8(DMF)4]·(DMF)}n (2) whereas diethyl ether vapor diffusion into the reaction solution gives {[Cu3Tb(L(Pr))W(CN)8(DMF)3(H2O)3]·(DMF)1.5·(H2O)0.5}n (3). Both compounds are obtained as black single crystals and feature one-dimensional (1D) coordination networks (chains) of [1](3+) macrocycles linked by [W(CN)8](3-) anions. The two assemblies differ from a structural point of view. Complex 2 has a stepped arrangement with the linkers bound to the opposite faces of the macrocycle, whereas 3 has a square-wave arrangement due to the linkers binding to the same face of the macrocycle. Both compounds display an antiferromagnetic ground state below 3.5 and 2.4 K with a metamagnetic and antiferromagnetic (T, H) phase diagram for 2 and 3, respectively. Remarkably the slow dynamics of the magnetization of the [1](3+) macrocycle units is preserved in 3 while this property is quenched in 2 because of stronger intra- and interchain magnetic interactions inducing a higher critical temperature. PMID:24224842

  16. Solvothermal Subcomponent Self-Assembly of Cubic Metal-Imidazolate Cages and Their Coordination Polymers.

    PubMed

    Luo, Dong; Zhou, Xiao-Ping; Li, Dan

    2015-11-16

    A series of Ni-imidazolate cubic cages, one-dimensional and two-dimensional coordination polymers based on the cubic cages, have been prepared by solvothermal subcomponent self-assembly of 5-methyl-4-formylimidazole, m-xylylenediamine, and Ni(II) salts with varied anions. These compounds have been characterized by single-crystal X-ray diffractions, elemental analysis, IR spectra, and powder X-ray diffractions. The formation of an oligomerized coordination cage or an infinite coordination polymer depends on the anions chosen. An oligomerized 8-nuclear Ni-imidazolate cubic cage is formed when the anion Cl(-), Br(-), I(-), SCN(-), NO2(-), or NO3(-) is utilized in the reactions, and a two-dimensional coordination polymer based on the Ni-imidazolate cubic cage will be obtained when N3(-), (CN)2N(-), or (CN)3C(-) act as the anions. When only ClO4(-) or both ClO4(-) and [Ni(C4N2S2)2](2-) (C4N2S2 = dimercaptomaleonitrile) as anions exist in the reaction mixture, a ladder-like one-dimensional coordination polymer based on the Ni-imidazolate cubic cage and formate is formed unpredictably. PMID:26513448

  17. Slow magnetic relaxation in lanthanide ladder type coordination polymers.

    PubMed

    Girginova, Penka I; Pereira, Laura C J; Coutinho, Joana T; Santos, Isabel C; Almeida, Manuel

    2014-01-28

    A series of four isostructural lanthanide-containing one dimensional coordination polymers with picolinic (pic) and glutaric (glu) acids, Ln(glu)(pic)(H2O)2, where Ln = Gd(III) (1), Tb(III) (2), Dy(III) (3) and Er(III) (4) were synthesized under hydrothermal conditions and structurally characterized by powder and single-crystal X-ray diffraction, elemental analysis, IR spectroscopy and thermogravimetric measurements. These compounds are isostructural to the previously reported Sm(glu)(pic)(H2O)2 and the structure consists in pairs of lanthanide ions double bridged by carboxylic groups which are connected along c by the glutaric acid ligands as a ladder type 1D coordination polymer. The magnetic properties of these compounds were studied by static magnetization and AC magnetic susceptibility measurements in the temperature range 1.7-300 K. Weak dominant ferromagnetic interactions between lanthanide cations were found in the compounds, except in compound 3. Compounds 1, 3 and 4 reveal frequency dependent AC susceptibility and slow relaxation of the magnetization under applied external static field. These data classify the Gd(III), Dy(III) and Er(III) compounds as molecular magnets. In spite of the ladder chain structure of the compounds this magnetic behaviour is not due to a single chain but instead it is ascribed to single ion anisotropic effects in the case of 3 and 4 and possibly to a phonon-bottleneck effect of the spin-lattice relaxation in 1. PMID:24264729

  18. Modular Synthesis of Functional Nanoscale Coordination Polymers

    PubMed Central

    Lin, Wenbin; Rieter, William J.; Taylor, Kathryn M. L.

    2013-01-01

    The coordination-directed assembly of metal ions and organic bridging ligands has afforded a variety of bulk-scale hybrid materials with promising characteristics for a number of practical applications, such as gas storage and heterogeneous catalysis. Recently, so-called coordination polymers have emerged as a new class of hybrid nanomaterials. Herein, we highlight advances in the syntheses of both amorphous and crystalline nanoscale coordination polymers. We also illustrate how scaling down these materials to the nano-regime has enabled their use in a broad range of applications including catalysis, spin-crossover, templating, biosensing, biomedical imaging, and anticancer drug delivery. These results underscore the exciting opportunities of developing next-generation functional nanomaterials based on molecular components. PMID:19065692

  19. Structural Flexibilities and Gas Adsorption Properties of One-Dimensional Copper(II) Polymers with Paddle-Wheel Units by Modification of Benzoate Ligands.

    PubMed

    Takahashi, Kiyonori; Hoshino, Norihisa; Takeda, Takashi; Noro, Shin-Ichiro; Nakamura, Takayoshi; Takeda, Sadamu; Akutagawa, Tomoyuki

    2015-10-01

    CO2 and N2 gas adsorption/desorption properties of one-dimensional copper(II) polymers with paddle-wheel units [Cu(II)2(p-XBA)4(pyrazine)]? were successfully controlled through the tuning of interchain interactions by modification of para-substituent X groups on the benzoate (BA) ligands (X = Cl, Br, I, and OCH3). Although none of the four crystals had sufficient void space to integrate the crystallization solvents, gate-opening gas adsorption and desorption behaviors coupled with structural phase transitions were observed for CO2 (T = 195 K) and N2 (T = 77 K), with differences depending on the precise substituent. van der Waals interchain interactions, specifically ?···?, halogen···?, and C-H···? contacts, were dominant in forming the crystal lattice; their magnitude was associated with gate-opening pressure and hysteresis behaviors. Both the type and magnitude of the interactions were evaluated by Hirshfeld surface analysis, which indicated that structural flexibility decreased as larger halogen atoms were included. Overall, weak interchain interaction and structural flexibility generated new void spaces to adsorb CO2 and N2 gases. PMID:26381225

  20. Synthesis, crystal structure and luminescence properties of lanthanide coordination polymers with a new semirigid bridging thenylsalicylamide ligand

    SciTech Connect

    Song, Xue-Qin Wang, Li; Zhao, Meng-Meng; Wang, Xiao-Run; Peng, Yun-Qiao; Cheng, Guo-Quan

    2013-09-15

    Two new lanthanide coordination polymers based on a semirigid bridging thenylsalicylamide ligand ([Ln{sub 2}L{sub 3}(NO{sub 3}){sub 6}]·(C{sub 4}H{sub 8}O{sub 2}){sub 2}){sub ?} were obtained and characterized by elemental analysis, X-ray diffraction, IR and TGA measurements. The two compounds are isostructure and possess one dimensional trapezoid ladder-like chain built up from the connection of isolated LnO{sub 3}(NO{sub 3}){sub 3} polyhedra (distorted monocapped antisquare prism) through the ligand. The photoluminescence analysis suggest that there is an efficient ligand-to-Ln(III) energy transfer in Tb(III) complex and the ligand is an efficient “antenna” for Tb(III). From a more general perspective, the results demonstrated herein provide the possibility of controlling the formation of the desired lanthanide coordination structure to enrich the crystal engineering strategy and enlarge the arsenal for developing excellent luminescent lanthanide coordination polymers. - Graphical abstract: We present herein one dimensional lanthanide coordination polymers of a new semirigid exo-bidentate ligand which not only display interesting structures but also possess strong luminescence properties. Display Omitted - Highlights: • We present lanthanide coordination polymers of a new semirigid exo-bidentate ligand. • The lanthanide coordination polymers exhibit interesting structures. • The luminescent properties of Tb(III) complexes are discussed in detail.

  1. Coordination polymers, metalorganic frameworks and the need for terminology

    E-print Network

    Paik Suh, Myunghyun

    Coordination polymers, metal­organic frameworks and the need for terminology guidelines Stuart R,*f Michael O'Keeffe,g Myunghyun Paik Suhh and Jan Reedijki,j DOI: 10.1039/c2ce06488j Coordination polymers converge into a self-consistent and logical result. This dual situation occurs for coordi- nation polymers

  2. Thin films of coordination polymer magnets.

    PubMed

    Talham, Daniel R; Meisel, Mark W

    2011-06-01

    Many applications of molecule based magnets, whether they are in information storage, displays, or as components in electronic or spintronic devices, will require putting the active materials on a surface or interfacing them with other components. Although there are many examples of molecule-based magnets, the families of tetracyanoethylene (TCNE) based magnets and Prussian-blue analogs possess materials properties that are close to those required for practical applications, and are the most advanced with respect to studies as thin films. This critical review focuses on fabrication and characterization of thin films of TCNE and Prussian-blue analog coordination polymer magnets. Emphasis is on current developments in thin film heterostructures and potential spintronics applications (135 references). PMID:21465059

  3. Syntheses, structural analyses and luminescent property of four alkaline-earth coordination polymers

    SciTech Connect

    Zhang, Sheng; Qu, Xiao-Ni; Xie, Gang; Wei, Qing; Chen, San-Ping

    2014-02-15

    Four alkaline-earth coordination polymers, [Ba(Pzdc)(H{sub 2}O)]{sub n} (1), [Ba(Pzdc)]{sub n} (2), [AgSr(Pzdc)(NO{sub 3})(H{sub 2}O)]{sub n} (3), [Ag{sub 2}Ca(Pzdc){sub 2}(H{sub 2}O)]{sub n} (4) (H{sub 2}Pzdc=2, 3-pyrazinedicarboxylic acid) have been synthesized and characterized by single-crystal X-ray diffraction. Compounds 1 and 2 afford 2D layer networks generated by one-dimensional chains containing the [Ba{sub 2}O{sub 11}N] units. Compound 3 is of 2D mixed-metal coordination network formed by one-dimensional chain units, while 4 is of a 3D heterometallic framework. Interestingly, 1 and 2 can undergo reversible SCSC structural transformation upon dehydration/rehydration of coordinated water molecules. In addition, the ?–? stacking interactions dominate fluorescent properties of compounds 1 and 2. - Graphical abstract: Four new coordination polymers [Ba(Pzdc)(H{sub 2}O)]{sub n} (1), [Ba(Pzdc)]{sub n} (2), [AgSr(Pzdc)(NO{sub 3})(H{sub 2}O)]{sub n} (3), [Ag{sub 2}Ca(Pzdc){sub 2}(H{sub 2}O)]{sub n} (4) (H{sub 2}Pzdc=2, 3-pyrazinedicarboxylic acid) have been synthesized. Compounds 1–3 display 2D topology structures and compound 4 exhibits a 3D topology structure. Fortunately, 1 and 2 undergo reversible dehydration/rehydration of coordinated water molecules. Display Omitted - Highlights: • All structures are generated by 1D chains. • 1 and 2 show reversible dehydration/rehydration of coordinated water molecules. • The ?–? stacking interactions dominate fluorescent properties of compounds 1 and 2.

  4. Two different anionic manganese(II) coordination polymers constructed through dicyanamide coordination bridges.

    PubMed

    Wang, Hui Ting

    2015-10-01

    In order to explore new metal coordination polymers and to search for new types of ferroelectrics among hybrid coordination polymers, two manganese dicyanamide complexes, poly[tetramethylammonium [di-?3-dicyanamido-?(6)N(1):N(3):N(5)-tri-?2-dicyanamido-?(6)N(1):N(5)-dimanganese(II)

  5. Coordination polymers from a highly flexible alkyldiamine-derived ligand: structure, magnetism and gas adsorption studies.

    PubMed

    Hawes, Chris S; Chilton, Nicholas F; Moubaraki, Boujemaa; Knowles, Gregory P; Chaffee, Alan L; Murray, Keith S; Batten, Stuart R; Turner, David R

    2015-10-28

    The synthesis and structural, magnetic and gas adsorption properties of a series of coordination polymer materials prepared from a new, highly flexible and internally functional tetrakis-carboxybenzyl ligand H4L derived from 1,2-diaminoethane have been examined. The compound poly-[Ni3(HL)2(OH2)4]·2DMF·2H2O 1, a two-dimensional coordination polymer, contains aqua- and carboxylato-bridged trinuclear Ni(II) clusters, the magnetic behaviour of which can be well described through experimental fitting and ab initio modelling to a ferromagnetically coupled trimer with a positive axial zero-field splitting parameter D. Compound poly-[Zn2L]·2DMF·3H2O 2, a three-dimensional coordination polymer displaying frl topology, contains large and well-defined solvent channels, which are shown to collapse on solvent exchange or drying. Compound poly-[Zn2(L)(DMSO)4]·3DMSO·3H2O 3, a highly solvated two-dimensional coordination polymer, displayed poor stability characteristics, however a structurally related material poly-[Zn2(L)(bpe)(DMSO)2]·DMSO·3H2O 4 was prepared under similar synthetic conditions by including the 1,2-bis(4-pyridyl)ethylene bpe co-ligand. Compound 4, containing small one-dimensional solvent channels, shows excellent structural resilience to solvent exchange and evacuation, and the evacuated material displays selective adsorption of CO2 over N2 at 273 K in the pressure range 0-1 atm. Each of the coordination polymers displays subtle differences in the conformation and binding mode of the ligand species, with switching between two distinct conformers (X-shaped and H-shaped), as well as a variable protonation state of the central core, with significant effects on the resulting network structures and physical properties of the materials. PMID:26223788

  6. Proton-Conducting Magnetic Coordination Polymers.

    PubMed

    Biswas, Soumava; Jena, Himanshu Sekhar; Sanda, Suresh; Konar, Sanjit

    2015-09-21

    Three isostructural lanthanide-based two- dimensional coordination polymers (CPs) {[Ln2(L)3(H2O)2]n?2n?CH3OH)?2n?H2O} (Ln=Gd(3+) (1), Tb(3+) (2), Dy(3+) (3); H2L=cyclobutane-1,1-dicarboxylic acid) were synthesized by using a low molecular weight dicarboxylate ligand and characterized. Single-crystal structure analysis showed that in complexes 1-3 lanthanide centers are connected by ?3-bridging cyclobutanedicarboxylate ligands along the c axis to form a rod-shaped infinite 1D coordination chain, which is further linked with nearby chains by ?4-connected cyclobutanedicarboxylate ligands to form 2D CPs in the bc plane. Viewing the packing of the complexes down the b axis reveals that the lattice methanol molecules are located in the interlayer space between the adjacent 2D layers and form H-bonds with lattice and coordinated water molecules to form 1D chains. Magnetic properties of complexes 1-3 were thoroughly investigated. Complex 1 exhibits dominant ferromagnetic interaction between two nearby gadolinium centers and also acts as a cryogenic magnetic refrigerant having a significant magnetic entropy change of -?Sm=32.8?J?kg(-1)?K(-1) for ?H=7?T at 4?K (calculated from isothermal magnetization data). Complex 3 shows slow relaxation of magnetization below 10?K. Impedance analysis revealed that the complexes show humidity-dependent proton conductivity (?=1.5×10(-5)?S?cm(-1) for 1, ?=2.07×10(-4)?S?cm(-1) for 2, and ?=1.1×10(-3)?S?cm(-1) for 3) at elevated temperature (>75?°C). They retain the conductivity for up to 10?h at high temperature and high humidity. Furthermore, the proton conductivity results were correlated with the number of water molecules from the water-vapor adsorption measurements. Water-vapor adsorption studies showed hysteretic and two-step water vapor adsorption (182,000??L?g(-1) for 1, 184,000??L?g(-1) for 2, and 1,874,000??L?g(-1) for 3) in the experimental pressure range. Simulation of water-vapor adsorption by the Monte Carlo method (for 1) confirmed the high density of adsorbed water molecules, preferentially in the interlayer space between the 2D layers. PMID:26274020

  7. Two unprecedented 1D coordination polymer chains based on tetranuclear copper(II) building blocks

    SciTech Connect

    Li Gaijuan; Xing Yan Song Shuyan; Xu Ning; Liu Xianchun; Su Zhongmin

    2008-09-15

    The reaction of copper(II) sulfate with pyridine in DMF or methanol yield two unprecedented Cu(II) coordination polymers {l_brace}[Cu{sub 4}({mu}{sub 4}-O)(py){sub 4}(SO{sub 4}){sub 4}][{mu}-Cu(py)(DMF){sub 2}]{r_brace}{sub n}(1) and {l_brace}[Cu{sub 4}({mu}{sub 4}-O)(py){sub 4}(SO{sub 4}){sub 4}][{mu}-Cu(py){sub 4}]{r_brace}{sub n}(2), respectively. Single-crystal X-ray diffraction indicated that compound 1 crystallizes in the monoclinic system, space group p2(1)/n, a=14.542(5) A, b=16.359(5) A, c=18.951(5) A, {beta}=92.047(5){sup o}, V=4505(2) A{sup 3}, Z=4 while 2 is monoclinic C2/c, a=23.078(5) A, b=10.214(5) A, c=23.142(5) A, {beta}=115.471(5){sup o}, V=4925(3) A{sup 3}, Z=4. Both of the two compounds consist of tetrahedral tetranuclear [Cu{sub 4}({mu}{sub 4}-O)(py){sub 4}(SO{sub 4}){sub 4}] clusters that are bridged by pentacoordinated Cu atom for 1 or hexacoordinated Cu atoms for 2 through the sulfate oxygen to form the infinite one-dimensional polymer chains. - Graphical abstract: Two unprecedented Cu(II) coordination polymers have been prepared by using solvothermal method; they consist of tetrahedral tetranuclear clusters that are bridged by unique Cu(II) atom through the sulfate oxygen to form the infinite one-dimensional polymer chains (a) for complex 1 and (b) for complex 2.

  8. Photocatalytic activity of PANI loaded coordination polymer composite materials: Photoresponse region extension and quantum yields enhancement via the loading of PANI nanofibers on surface of coordination polymer

    SciTech Connect

    Cui, Zhongping; Qi, Ji; Xu, Xinxin Liu, Lu; Wang, Yi

    2013-09-15

    To enhance photocatalytic property of coordination polymer in visible light region, polyaniline (PANI) loaded coordination polymer photocatalyst was synthesized through in-situ chemical oxidation of aniline on the surface of coordination polymer. The photocatalytic activity of PANI loaded coordination polymer composite material for degradation of Rhodamine B (RhB) was investigated. Compared with pure coordination polymer photocatalyst, which can decompose RhB merely under UV light irradiation, PANI loaded coordination polymer photocatalyst displays more excellent photocatalytic activity in visible light region. Furthermore, PANI loaded coordination polymer photocatalyst exhibits outstanding stability during the degradation of RhB. - Graphical abstract: PANI loaded coordination polymer composite material, which displays excellent photocatalytic activity under visible light was firstly synthesized through in-situ chemical oxidation of aniline on surface of coordination polymer. Display Omitted - Highlights: • This PANI loaded coordination polymer composite material represents the first conductive polymer loaded coordination polymer composite material. • PANI/coordination polymer composite material displays more excellent photocatalytic activity for the degradation of MO in visible light region. • The “combination” of coordination polymer and PANI will enable us to design high-activity, high-stability and visible light driven photocatalyst in the future.

  9. Crystal structures and luminescent properties of lanthanide nitrate coordination polymers with structurally related amide type bridging podands

    SciTech Connect

    Wang, Qing; Yan, Xuhuan; Zhang, Hongrui; Liu, Weisheng; Tang, Yu; Tan, Minyu

    2011-01-15

    A one-dimensional linear chain coordination polymer [ErL{sup I}(NO{sub 3}){sub 3}(CH{sub 3}CO{sub 2}Et)]{sub n} (L{sup I}=1,2-bis{l_brace}[(2'-furfurylaminoformyl)phenoxyl]methyl{r_brace}benzene) and a one-dimensional zig-zag coordination polymer {l_brace}[TbL{sup II}(NO{sub 3}){sub 3}(H{sub 2}O)].(H{sub 2}O){r_brace}{sub n} (L{sup II}=1,2-bis{l_brace}[2'-(2-pyridylmethylaminoformyl)phenoxyl]methyl{r_brace}benzene) were assembled by two structurally related bridging podands L{sup I} and L{sup II} which have uniform skeleton and different terminal groups. In {l_brace}[TbL{sup II}(NO{sub 3}){sub 3}(H{sub 2}O)].(H{sub 2}O){r_brace}{sub n}, the neutral chains were linked by the hydrogen bonding interactions between the free and coordinated water molecules from two different directions to interpenetrate into a 3D supramolecular structure. At the same time, the luminescent properties of the solid Tb(III) nitrate complexes of these podands were investigated at room temperature. The lowest triplet state energy levels T{sub 1} of the podands L{sup I} and L{sup II} indicate that the triplet state energy levels of the antennae are both above the lowest excited resonance level of {sup 5}D{sub 4} of Tb{sup 3+} ion. Thus the absorbed energy could be transferred from ligands to the central Tb{sup 3+} ions. And the influence of the hydrogen bonding on the luminescence efficiencies of the coordination polymers was also discussed. -- Graphical Abstract: Two one-dimensional lanthanide coordination polymers were assembled by two structurally related bridging podands, and the effects of the structures on luminescent properties of the solid Tb(III) nitrate complexes were investigated. Display Omitted Research highlights: > Two structurally related amide type bridging ligands were designed and synthesized. > Two one dimensional lanthanide nitrate coordination polymers were obtained. > The structure effects on luminescent properties of the terbium complexes were discussed.

  10. Nanoscale coordination polymers for anticancer drug delivery

    NASA Astrophysics Data System (ADS)

    Phillips, Rachel Huxford

    This dissertation reports the synthesis and characterization of nanoscale coordination polymers (NCPs) for anticancer drug delivery. Nanoparticles have been explored in order to address the limitations of small molecule chemotherapeutics. NCPs have been investigated as drug delivery vehicles as they can exhibit the same beneficial properties as the bulk metal-organic frameworks as well as interesting characteristics that are unique to nanomaterials. Gd-MTX (MTX = methotrexate) NCPs with a MTX loading of 71.6 wt% were synthesized and stabilized by encapsulation within a lipid bilayer containing anisamide (AA), a small molecule that targets sigma receptors which are overexpressed in many cancer tissues. Functionalization with AA allows for targeted delivery and controlled release to cancer cells, as shown by enhanced efficacy against leukemia cells. The NCPs were doped with Ru(bpy)32+ (bpy = 2,2'-bipyridine), and this formulation was utilized as an optical imaging agent by confocal microscopy. NCPs containing the chemotherapeutic pemetrexed (PMX) were synthesized using different binding metals. Zr-based materials could not be stabilized by encapsulation with a lipid bilayer, and Gd-based materials showed that PMX had degraded during synthesis. However, Hf-based NCPs containing 19.7 wt% PMX were stabilized by a lipid coating and showed in vitro efficacy against non-small cell lung cancer (NSCLC) cell lines. Enhanced efficacy was observed for formulations containing AA. Additionally, NCP formulations containing the cisplatin prodrug disuccinatocisplatin were prepared; one of these formulations could be stabilized by encapsulation within a lipid layer. Coating with a lipid layer doped with AA rendered this formulation an active targeting agent. The resulting formulation proved more potent than free cisplatin in NSCLC cell lines. Improved NCP uptake was demonstrated by confocal microscopy and competitive binding assays. Finally, a Pt(IV) oxaliplatin prodrug was synthesized and incorporated in different NCPs using various binding metals. A moderate drug loading of 44.9 wt% was determined for Zr-based NCPs. This drug loading, along with a diameter less than 200 nm, make these particles promising candidates for further stabilization via lipid encapsulation.

  11. Preparation of Highly Porous Coordination Polymer Coatings on Macroporous Polymer Monoliths for Enhanced Enrichment of Phosphopeptides.

    PubMed

    Lamprou, Alexandros; Wang, Hongxia; Saeed, Adeela; Svec, Frantisek; Britt, David; Maya, Fernando

    2015-01-01

    We describe a protocol for the preparation of hybrid materials based on highly porous coordination polymer coatings on the internal surface of macroporous polymer monoliths. The developed approach is based on the preparation of a macroporous polymer containing carboxylic acid functional groups and the subsequent step-by-step solution-based controlled growth of a layer of a porous coordination polymer on the surface of the pores of the polymer monolith. The prepared metal-organic polymer hybrid has a high specific micropore surface area. The amount of iron(III) sites is enhanced through metal-organic coordination on the surface of the pores of the functional polymer support. The increase of metal sites is related to the number of iterations of the coating process. The developed preparation scheme is easily adapted to a capillary column format. The functional porous polymer is prepared as a self-contained single-block porous monolith within the capillary, yielding a flow-through separation device with excellent flow permeability and modest back-pressure. The metal-organic polymer hybrid column showed excellent performance for the enrichment of phosphopeptides from digested proteins and their subsequent detection using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The presented experimental protocol is highly versatile, and can be easily implemented to different organic polymer supports and coatings with a plethora of porous coordination polymers and metal-organic frameworks for multiple purification and/or separation applications. PMID:26273850

  12. Self-consistent field theory of tethered polymers: One dimensional, three dimensional, strong stretching theories and the effects of excluded-volume-only interactions

    SciTech Connect

    Suo, Tongchuan Whitmore, Mark D.

    2014-11-28

    We examine end-tethered polymers in good solvents, using one- and three-dimensional self-consistent field theory, and strong stretching theories. We also discuss different tethering scenarios, namely, mobile tethers, fixed but random ones, and fixed but ordered ones, and the effects and important limitations of including only binary interactions (excluded volume terms). We find that there is a “mushroom” regime in which the layer thickness is independent of the tethering density, ?, for systems with ordered tethers, but we argue that there is no such plateau for mobile or disordered anchors, nor is there one in the 1D theory. In the other limit of brushes, all approaches predict that the layer thickness scales linearly with N. However, the ?{sup 1/3} scaling is a result of keeping only excluded volume interactions: when the full potential is included, the dependence is faster and more complicated than ?{sup 1/3}. In fact, there does not appear to be any regime in which the layer thickness scales in the combination N?{sup 1/3}. We also compare the results for two different solvents with each other, and with earlier ? solvent results.

  13. Self-consistent field theory of tethered polymers: One dimensional, three dimensional, strong stretching theories and the effects of excluded-volume-only interactions

    NASA Astrophysics Data System (ADS)

    Suo, Tongchuan; Whitmore, Mark D.

    2014-11-01

    We examine end-tethered polymers in good solvents, using one- and three-dimensional self-consistent field theory, and strong stretching theories. We also discuss different tethering scenarios, namely, mobile tethers, fixed but random ones, and fixed but ordered ones, and the effects and important limitations of including only binary interactions (excluded volume terms). We find that there is a "mushroom" regime in which the layer thickness is independent of the tethering density, ?, for systems with ordered tethers, but we argue that there is no such plateau for mobile or disordered anchors, nor is there one in the 1D theory. In the other limit of brushes, all approaches predict that the layer thickness scales linearly with N. However, the ?1/3 scaling is a result of keeping only excluded volume interactions: when the full potential is included, the dependence is faster and more complicated than ?1/3. In fact, there does not appear to be any regime in which the layer thickness scales in the combination N?1/3. We also compare the results for two different solvents with each other, and with earlier ? solvent results.

  14. Photoluminescent lead(II) coordination polymers stabilised by bifunctional organoarsonate ligands

    NASA Astrophysics Data System (ADS)

    Lin, Jian-Di; Onet, Camelia I.; Schmitt, Wolfgang

    2015-04-01

    Four lead(II) coordination polymers were isolated under hydro(solvo)thermal conditions. The applied synthetic methodology takes advantage of the coordination behaviour of a new bifunctional organoarsonate ligand, 4-(1, 2, 4-triazol-4-yl)phenylarsonic acid (H2TPAA) and involves the variation of lead(II) reactants, metal/ligand mole ratios, and solvents. The constitutional composition of the four lead(II) coordination polymers can be formulated as [Pb2(TPAA)(HTPAA)(NO3)]·6H2O (1), [Pb2(TPAA)(HTPAA)2]·DMF·0.5H2O (DMF = N, N-Dimethylformamide) (2), [Pb2Cl2(TPAA)H2O] (3), and [Pb3Cl(TPAA)(HTPAA)2H2O]Cl (4). The compounds were characterized by single-crystal and powder x-ray diffraction techniques, thermogravimetric analyses, infra-red spectroscopy, and elemental analyses. Single-crystal x-ray diffraction reveals that 1 and 2 represent two-dimensional (2D) layered structures whilst 3 and 4 form three-dimensional (3D) frameworks. The structures of 1, 2, and 4 contain one-dimensional (1D) {PbII/AsO3} substructures, while 3 is composed of 2D {PbII/AsO3} arrays. Besides their interesting topologies, 1-4 all exhibit photoluminescence properties in the solid state at room temperature.

  15. Crystal engineering of lanthanide transition-metal coordination polymers

    NASA Astrophysics Data System (ADS)

    Gu, Xiaojun; Xue, Dongfeng; Ratajczak, Henryk

    2008-09-01

    Crystal engineering allows us to predict and control the packing of molecular building units in solid state, which has been attracting much attention due to its exploitation for the synthesis of crystalline materials with novel structures and promising properties. The crystal engineering strategies toward the synthesis of high-nuclearity lanthanide clusters and three-dimensional (3D) lanthanide-transition-metal (Ln-M) coordination polymers were well discussed in the present work. It has shown that the high-nuclearity lanthanide clusters can be rationally synthesized by surface modification strategy. On the basis of the different coordination nature of lanthanide and transition-metal ions, the multifunctional organic ligands with mixed coordination sites such as isonicotinate have been elaborately selected to rationally construct a series of homochrial and achiral 3D Ln-M coordination frameworks built from inorganic heterometallic chains with improved thermal stability. Furthermore, novel 3D Ln-M coordination frameworks have been built from discrete lanthanide clusters (or cluster polymers) and transition-metal clusters (or cluster polymers) by faultlessly harmonizing the subtle relationship between these two different types of metal cluster or cluster polymer units. The current work offers us great potential toward the pursuit of rational synthesis of Ln-M coordination assemblies on the basis of crystal engineering principles.

  16. Mixing of immiscible polymers using nanoporous coordination templates.

    PubMed

    Uemura, Takashi; Kaseda, Tetsuya; Sasaki, Yotaro; Inukai, Munehiro; Toriyama, Takaaki; Takahara, Atsushi; Jinnai, Hiroshi; Kitagawa, Susumu

    2015-01-01

    The establishment of methodologies for the mixing of immiscible substances is highly desirable to facilitate the development of fundamental science and materials technology. Herein we describe a new protocol for the compatibilization of immiscible polymers at the molecular level using porous coordination polymers (PCPs) as removable templates. In this process, the typical immiscible polymer pair of polystyrene (PSt) and poly(methyl methacrylate) (PMMA) was prepared via the successive homopolymerizations of their monomers in a PCP to distribute the polymers inside the PCP particles. Subsequent dissolution of the PCP frameworks in a chelator solution affords a PSt/PMMA blend that is homogeneous in the range of several nanometers. Due to the unusual compatibilization, the thermal properties of the polymer blend are remarkably improved compared with the conventional solvent-cast blend. This method is also applicable to the compatibilization of PSt and polyacrylonitrile, which have very different solubility parameters. PMID:26130294

  17. Mixing of immiscible polymers using nanoporous coordination templates

    PubMed Central

    Uemura, Takashi; Kaseda, Tetsuya; Sasaki, Yotaro; Inukai, Munehiro; Toriyama, Takaaki; Takahara, Atsushi; Jinnai, Hiroshi; Kitagawa, Susumu

    2015-01-01

    The establishment of methodologies for the mixing of immiscible substances is highly desirable to facilitate the development of fundamental science and materials technology. Herein we describe a new protocol for the compatibilization of immiscible polymers at the molecular level using porous coordination polymers (PCPs) as removable templates. In this process, the typical immiscible polymer pair of polystyrene (PSt) and poly(methyl methacrylate) (PMMA) was prepared via the successive homopolymerizations of their monomers in a PCP to distribute the polymers inside the PCP particles. Subsequent dissolution of the PCP frameworks in a chelator solution affords a PSt/PMMA blend that is homogeneous in the range of several nanometers. Due to the unusual compatibilization, the thermal properties of the polymer blend are remarkably improved compared with the conventional solvent-cast blend. This method is also applicable to the compatibilization of PSt and polyacrylonitrile, which have very different solubility parameters. PMID:26130294

  18. Strategies, linkers and coordination polymers for high-performance sorbents

    SciTech Connect

    Matzger, Adam J.; Wong-Foy, Antek G.; Lebel, Oliver

    2015-09-15

    A linking ligand compound includes three bidentate chemical moieties distributed about a central chemical moiety. Another linking ligand compound includes a bidentate linking ligand and a monodentate chemical moiety. Coordination polymers include a plurality of metal clusters linked together by residues of the linking ligand compounds.

  19. Unusual Transformation from a Solvent-Stabilized 1D Coordination Polymer to a Metal-Organic Framework (MOF)-Like Cross-Linked 3D Coordination Polymer.

    PubMed

    Lee, Seung-Chul; Choi, Eun-Young; Lee, Sang-Beom; Kim, Sang-Wook; Kwon, O-Pil

    2015-10-26

    An unusual 1D-to-3D transformation of a coordination polymer based on organic linkers containing highly polar push-pull ?-conjugated side chains is reported. The coordination polymers are synthesized from zinc nitrate and an organic linker, namely, 2,5-bis{4-[1-(4-nitrophenyl)pyrrolidin-2-yl]butoxy}terephthalic acid, which possesses highly polar (4-nitrophenyl)pyrrolidine groups, with high dipole moments of about 7?D. The coordination polymers exhibit an unusual transformation from a soluble, solvent-stabilized 1D coordination polymer into an insoluble, metal-organic framework (MOF)-like 3D coordination polymer. The coordination polymer exhibits good film-forming ability, and the MOF-like films are insoluble in conventional organic solvents. PMID:26493879

  20. Solvent-vapour-assisted pathways and the role of pre-organization in solid-state transformations of coordination polymers

    PubMed Central

    Wright, James S.; Vitórica-Yrezábal, Iñigo J.; Adams, Harry; Thompson, Stephen P.; Hill, Adrian H.; Brammer, Lee

    2015-01-01

    A family of one-dimensional coordination polymers, [Ag4(O2C(CF2)2CF3)4(phenazine)2(arene)n]·m(arene), 1 (arene = toluene or xylene), have been synthesized and crystallographically characterized. Arene guest loss invokes structural transformations to yield a pair of polymorphic coordination polymers [Ag4(O2C(CF2)2CF3)4(phenazine)2], 2a and/or 2b, with one- and two-dimensional architectures, respectively. The role of pre-organization of the polymer chains of 1 in the selectivity for formation of either polymorph is explored, and the templating effect of toluene and p-xylene over o-xylene or m-xylene in the formation of arene-containing architecture 1 is also demonstrated. The formation of arene-free phase 2b, not accessible in a phase-pure form through other means, is shown to be the sole product of loss of toluene from 1-tol·tol [Ag4(O2C(CF2)2CF3)4(phenazine)2(toluene)]·2(toluene), a phase containing toluene coordinated to Ag(I) in an unusual ?:?1,?1 manner. Solvent-vapour-assisted conversion between the polymorphic coordination polymers and solvent-vapour influence on the conversion of coordination polymers 1 to 2a and 2b is also explored. The transformations have been examined and confirmed by X-ray diffraction, NMR spectroscopy and thermal analyses, including in situ diffraction studies of some transformations. PMID:25866656

  1. One-Dimensional Heat Conduction

    Energy Science and Technology Software Center (ESTSC)

    1992-03-09

    ICARUS-LLNL was developed to solve one-dimensional planar, cylindrical, or spherical conduction heat transfer problems. The IBM PC version is a family of programs including ICARUSB, an interactive BASIC heat conduction program; ICARUSF, a FORTRAN heat conduction program; PREICAR, a BASIC preprocessor for ICARUSF; and PLOTIC and CPLOTIC, interpretive BASIC and compiler BASIC plot postprocessor programs. Both ICARUSB and ICARUSF account for multiple material regions and complex boundary conditions, such as convection or radiation. In addition,more »ICARUSF accounts for temperature-dependent material properties and time or temperature-dependent boundary conditions. PREICAR is a user-friendly preprocessor used to generate or modify ICARUSF input data. PLOTIC and CPLOTIC generate plots of the temperature or heat flux profile at specified times, plots of the variation of temperature or heat flux with time at selected nodes, or plots of the solution grid. First developed in 1974 to allow easy modeling of complex one-dimensional systems, its original application was in the nuclear explosive testing program. Since then it has undergone extensive revision and been applied to problems dealing with laser fusion target fabrication, heat loads on underground tests, magnetic fusion switching tube anodes, and nuclear waste isolation canisters.« less

  2. One-dimensional Quantum Fluids

    NASA Astrophysics Data System (ADS)

    Gervais, Guillaume

    2015-03-01

    Fifty year ago, Joachim Mazdak Luttinger generalized the Tomonaga theory of interactions in a one-dimensional metal and show that the prior restrictions imposed by Tomonaga were not necessary. This model is now known as the Tomonaga- Luttinger liquid model (TLL) and most remarkably it does have mathematically exact solutions. In the case of electrons, it predicts that the spin and charge sector should separate, with each of them propagating with their own velocities. While there has been many attempts (some with great success) to observe TLL behaviour in clean quantum wires designed on an ultra-clean semiconductor platform, overall the Luttinger physics is experimentally still in its infancy. For instance, little is known regarding the 1D physics in a strongly-interacting neutral system, whether from the point-of-view of TLL theory or even localization physics. Helium-4, the paradigm superfluid, and Helium-3, the paradigm Fermi liquid, should in principleboth become Luttinger liquids if taken to the one-dimensional limit. In the bosonic case, this is supported by large-scale Quantum Monte Carlo simulations which found that a lengthscale of ~ 2 nm is sufficient for the system to crossover to the 1D regime and display universal Luttinger scaling. At McGill University, an experiment has been constructed to measure the liquid helium mass flow through a single nanopore. The technique consists of drilling a single nanopore in a SiN membrane using a TEM, and then applying a pressure gradient across the membrane. Previously published data in 45nm diameter hole determined the superfluid critical velocity to be close to the limit set by the Feynman vortex rings model. More recent work performed on nanopores with radii as small as 3 nm (and a length of 30nm) show the critical exponent for superfluid velocity to significantly deviate from its bulk value, 2/3. This is an important hint for the crossing over to the one-dimensional state in a strongly-correlated bosonic liquid.

  3. One Dimensional Simulation of LAPPS*

    NASA Astrophysics Data System (ADS)

    Joyce, Glenn; Fernsler, Richard F.

    2002-10-01

    We have developed a one-dimensional fluid simulation code for studies of the Large Area Plasma Processing System (LAPPS) at the Naval Research Laboratory. The code is time dependent, can be run in a quasi-neutral or electrostatic mode, solving Poissons equation and in the latter mode can resolve the plasma sheath. The code is multi-species, where the species are easily included by supplying the appropriate collision frequencies. The electron species is treated in the collision approximation in which inertial terms are neglected, but the ion equations include all inertial terms^1. The simulation direction is perpendicular to the electron beam used to produce the LAPPS plasma and to the beam-confining magnetic field. The effect of the magnetic field is represented by an enhanced electron diffusion coefficient. The electron beam is represented by a source of electrons in an interior region of the plasma. We present results for various gases and combinations of gases with parameters based on LAPPS experiments. We pay particular attention to the sheath-presheath interface and to the properties of ion flow at this interface. * Work supported by ONR 1. J.D. Huba, G. Joyce, and J.A. Fedder, JGR, 105, 23035, (2000)

  4. Self-assembly using dynamic coordination chemistry and hydrogen bonding: mercury(II) macrocycles, polymers and sheets.

    PubMed

    Burchell, Tara J; Eisler, Dana J; Puddephatt, Richard J

    2004-09-01

    The self-assembly of extended metal-containing arrays is described based on dynamic coordination chemistry at mercury(II) with bis(amidopyridyl) ligands to form macrocycles, polymers, or sheets which can be further organized by hydrogen bonding between amide substituents. The ligands 1,2-C6H4[NHC(O)-4-C5H4N]2, 1, 1,2-C(6)H(4)[C(O)NHCH(2)-4-C(5)H(4)N](2), 2, and 1,2-C(6)H(4)[CH(2)C(O)NHCH(2)-4-C(5)H(4)N]2, 3 can adopt polar conformations and so can confer helicity in their complexes. Several macrocycles of formula [(HgX(2))(2)(micro-LL)(2)] (LL = 1, 2), with tetrahedral mercury(II) centers, were prepared in which individual molecules are further self-assembled via hydrogen bonding in the solid state to form one- or two-dimensional polymers or sheets. In one case, a one-dimensional polymer [((HgX2)-(mu-3))n] was formed. It is shown that the mercury(II) centers can be six-coordinate in forming the sheet structure [((HgX2)(mu-2)2)n], in which there are particularly large pores. PMID:15332806

  5. (1-Butyl-4-methyl-pyridinium)[Cu(SCN)2]: a coordination polymer and ionic liquid.

    PubMed

    Spielberg, Eike T; Edengeiser, Eugen; Mallick, Bert; Havenith, Martina; Mudring, Anja-Verena

    2014-04-25

    The compound (C4C1py)[Cu(SCN)2], (C4C1py = 1-Butyl-4-methyl-pyridinium), which can be obtained from CuSCN and the ionic liquid (C4C1py)(SCN), turns out to be a new organic-inorganic hybrid material as it qualifies both, as a coordination polymer and an ionic liquid. It features linked [Cu(SCN)2](-) units, in which the thiocyanates bridge the copper ions in a ?1,3-fashion. The resulting one-dimensional chains run along the a?axis, separated by the C4C1py counterions. Powder X-ray diffraction not only confirms the single-crystal X-ray structure solution but proves the reformation of the coordination polymer from an isotropic melt. However, the materials shows a complex thermal behavior often encountered for ionic liquids such as a strong tendency to form a supercooled melt. At a relatively high cooling rate, glass formation is observed. When heating this melt in differential scanning calorimetry (DSC) and temperature-dependent polarizing optical microscopy (POM), investigations reveal the existence of a less thermodynamically stable crystalline polymorph. Raman measurements conducted at 10 and 100?°C point towards the formation of polyanionic chain fragments in the melt. Solid-state UV/Vis spectroscopy shows a broad absorption band around 18,870?cm(-1) (530?nm) and another strong one below 20,000?cm(-1) (<500?nm). The latter is attributed to the d(Cu(I))??*(SCN)-MLCT (metal-to-ligand charge transfer) transition within the coordination polymer yielding an energy gap of 2.4?eV. At room temperature and upon irradiation with UV light, the material shows a weak fluorescence band at 15,870?cm(-1) (630?nm) with a quantum efficiency of 0.90(2)?% and a lifetime of 131(2)?ns. Upon lowering the temperature, the luminescence intensity strongly increases. Simultaneously, the band around 450?nm in the excitation spectrum decreases. PMID:24644064

  6. One-dimensional coordination polymers constructed from bicapped Keggin polyoxometalate and cyclic tetranuclear Cu I cluster bridged by asymmetrical bipyridine derivative

    NASA Astrophysics Data System (ADS)

    Tian, Aixiang; Han, Zhangang; Peng, Jun; Sha, Jingquan; Zhao, Yulong; Pang, Haijun; Zhang, Pengpeng; Zhu, Min

    2008-10-01

    This article reports two new bicapped Keggin-based hybrid compounds, {[Cu 4I(cppy) 4][PMo 7VIMo 5VO 40(V IVO) 2]}·2H 2O ( 1) and {[Cu 4I(cppy) 4][SiMo 8VIMo 4VO 40(V IVO) 2]}·2H 2O ( 2) (cppy = 4-(5-(4-chlorophenyl)pyridin-2-yl)pyridine), synthesized under hydrothermal conditions and characterized by X-ray single-crystal diffraction, elemental analyses, IR, XPS, TG and CV analyses. Structural characterization shows that the two compounds are isostructural, consisting of square tetranuclear [Cu 4I(cppy) 4] 4+ circuits and reduced bivanadyl Keggin clusters. The tetranuclear [Cu 4I(cppy) 4] 4+ circuit is 'windstick'-style. The polyoxoanions acting as junctures connect the tetranuclear circuits to construct a chain. These chains are further connected through ?⋯? interactions, halogen bonding and hydrogen bonding interactions to construct a 3D superamolecular structure. The electrochemical behaviors of the 1-CPE have been studied in detail.

  7. Long-range order in the one-dimensional cobalt(II)-radical coordination polymer magnet probed by muon-spin rotation and relaxation.

    PubMed

    Ishida, Takayuki; Okamura, Yoshitomo; Watanabe, Isao

    2009-08-01

    A long-range-ordered state of CoBPNN was characterized by muSR. The temperature at the depolarization rate divergence (40 K) is defined as a magnetic transition temperature (T(N)). The phase is unique below T(N), but gradual freezing of the domain-wall motion finally leads to the magnetically hard character. PMID:19722688

  8. Two-Dimensional Coordination Polymers with One-Dimensional Magnetic Chains: Hydrothermal Synthesis, Crystal Structure, and Magnetic and Thermal Properties of

    E-print Network

    Li, Jing

    , Crystal Structure, and Magnetic and Thermal Properties of 2 [MCl2(4,4-bipyridine)] (M ) Fe, Co, Ni, Co to orthorhombic crystal system, space group Cmmm (No. 65). Crystal data for I: a ) 11.929(2) Å, b ) 11.447(2) Å, c ) 3.638(1) Å, V ) 496.77(18) Å3, Z ) 2. Crystal data for II: a ) 11.993(2) Å, b ) 11.374(2) Å, c ) 3

  9. One- and two-dimensional Cd(II) coordination polymers incorporating organophosphinate ligands.

    PubMed

    Rood, Jeffrey A; Boyer, Steven; Oliver, Allen G

    2014-11-01

    Reaction of cadmium nitrate with diphenylphosphinic acid in dimethylformamide solvent yielded the one-dimensional coordination polymer catena-poly[[bis(dimethylformamide-?O)cadmium(II)]-bis(?-diphenylphosphinato-?(2)O:O')], [Cd(C12H10O2P)2(C3H7NO)2]n, (I). Addition of 4,4'-bipyridine to the synthesis afforded a two-dimensional extended structure, poly[[(?-4,4'-bipyridine-?(2)N:N')bis(?-diphenylphosphinato-?(2)O:O')cadmium(II)] dimethylformamide monosolvate], {[Cd(C12H10O2P)2(C10H8N2)]·C3H7NO}n, (II). In (II), the 4,4'-bipyridine molecules link the Cd(II) centers in the crystallographic a direction, while the phosphinate ligands link the Cd(II) centers in the crystallographic b direction to complete a two-dimensional sheet structure. Consideration of additional ?-? interactions of the phenyl rings in (II) produces a three-dimensional structure with channels that encapsulate dimethylformamide molecules as solvent of crystallization. Both compounds were characterized by single-crystal X-ray diffraction and FT-IR analysis. PMID:25370109

  10. New silver(I) coordination polymers constructed from pyrazine derivatives and aromatic carboxylic acids: Syntheses, structures and photoluminescence

    NASA Astrophysics Data System (ADS)

    Zhang, Ting; Huang, Hua-Qi; Mei, Hong-Xin; Wang, Dan-Feng; Wang, Xiao-Xiang; Huang, Rong-Bin; Zheng, Lan-Sun

    2015-11-01

    Five one-dimensional to three-dimensional coordination polymers have been synthesized by 2-chlorobenzoic acid (HL1), 2-nitrobenzoic acid (HL2), o-toluic acid (HL3), 2,3,5-trimethylpyrazine (tpyz) and 2,3,5,6-tetramethylpyrazine (mpyz) in the presence of NH3·H2O in mixed solvents systems, namely, {Ag4(tpyz)2(L1)4}n (1), {Ag2(tpyz) (L2)2}n (2), {Ag2(tpyz) (L3)2}n (3), {Ag2(mpyz) (L1)2}n (4), {Ag(mpyz) (L2) (H2O)}n (5). All the complexes have been characterized by elemental analyses, IR spectra and X-ray diffraction. Compound 1 shows a 3D framework. The tpyz ligand links 1D chain which was connected by silver atom and L1 anion into 3D framework. Compounds 2 and 4 possess a similar 2D network with (4, 4) topology. Complex 3 also exhibits a two-dimensional structure. There is a 1D silver chain in 3, which is the main difference from 2 and 4. So, 3 shows three-connected (4 8, 3) topology. For 5, only one oxygen of L2 coordinated to Ag(I) ions. The L2 anions were arranged in both sides of the chain, which was connected by silver atoms and mpyz ligands. Then, the uncoordinated carboxylate oxygen with coordinated water 1molecule oxygen through the hydrogen bond made the resultant structure to a 3D framework. Complexes 1-5 spanning from one-dimensional chains to three-dimensional framework suggest that carboxylates and the kinds of pyrazine derivatives play significant roles in the formation of such coordination architectures. The photoluminescence and thermogravimetric analysis (TGA) of the complexes were also investigated.

  11. Mixed ligand coordination polymer based on 5-nitroisophthalic acid and 1-(4-nitrophenyl)-1,2,4-triazole: Synthesis, characterization, magnetic and photocatalytic properties

    NASA Astrophysics Data System (ADS)

    Li, Le; Ju, Wen-Wen; Tao, Jian-Qing; Xin, Rong; Wang, Jun; Xu, Xiao-Juan

    2015-09-01

    A new Cu(II) coordination polymer, namely, [Cu(NPT)2(NO2-BDC)]n (1) (NO2-H2BDC = 5-nitro-1,3-benzenedicarboxylic acid, NPT = 4-(4-nitrophenyl)-1,2,4-triazole) has been synthesized under hydrothermal condition and characterized by elemental analysis, and single-crystal X-ray diffraction. Single-crystal X-ray diffraction study reveals that complex 1 features one-dimensional chain structure. The magnetic studies reveal that the antiferromagnetic interactions exist between the adjacent CuII ions. Moreover, complex 1 displays highly photocatalytic degradation activity for the degradation of rhodamine B, methylene blue and methyl orange.

  12. Reversible Single-Crystal to Single-Crystal Transformations of a Zn(II)-Salicyaldimine Coordination Polymer Accompanying Changes in Coordination Sphere and Network Dimensionality upon Dehydration and Rehydration.

    PubMed

    Wu, Jing-Yun; Chang, Ching-Yun; Tsai, Chi-Jou; Lee, Jey-Jau

    2015-11-16

    A fluorescent Zn(II)-salicyaldimine coordination polymer, [Zn(L(salpyca))(H2O)]n (1; H2L(salpyca) = 4-hydroxy-3-(((pyridin-2-yl)methylimino)methyl)benzoic acid), showing a one-dimensional (1D) zigzag chain structure has been hydro(solvo)thermally synthesized. Removal of coordination water molecules in 1 by thermal dehydration gives rise to the dehydration product [Zn(L(salpyca))]n (1'), which has a dizinc-based two-dimensional (2D) gridlike (4,4)-layer structure. X-ray powder diffraction (XRPD) patterns, thermogravimetric (TG) analyses, and infrared (IR) spectra all clearly indicate that the structure of 1 is quite flexible as a result of a reversible 1D-2D single-crystal to single-crystal (SCSC) transformation upon removal and rebinding of coordination water molecules, which accompanies changes in coordination sphere and network dimensionality. Additionally, Zn(II)-salicyaldimine polymers 1 and 1' exhibit different solid-state photoluminescences at 458 and 480 nm, respectively. This is reasonably attributed to the close-packing effect and/or the influences of the differences on the conformation and the coordination mode of the L(salpyca) ligand and the coordination geometry around the Zn(II) center. PMID:26513649

  13. Supramolecular Coordination Polymer Formed from Artificial Light-Harvesting Dendrimer.

    PubMed

    Lee, Hosoowi; Jeong, Young-Hwan; Kim, Joo-Ho; Kim, Inhye; Lee, Eunji; Jang, Woo-Dong

    2015-09-30

    We report the formation of supramolecular coordination polymers formed from multiporphyrin dendrimers (PZnPM; M = FB or Cu), composed of the focal freebase porphyrin (PFB) or cupper porphyrin (PCu) with eight zinc porphyrin (PZn) wings, and multipyridyl porphyrins (PyPM; M = FB or Cu), PFB or PCu with eight pyridyl groups, through multiple axial coordination interactions of pyridyl groups to PZns. UV-vis absorption spectra were recorded upon titration of PyPFB to PZnPFB. Differential spectra, obtained by subtracting the absorption of PZnPFB without guest addition as well as the absorption of PyPFB, exhibited clear isosbestic points with saturation binding at 1 equiv addition of PyPFB to PZnPFB. Job's plot analysis also indicated 1:1 stoichiometry for the saturation binding. The apparent association constant between PZnPFB and PyPFB (2.91 × 10(6) M(-1)), estimated by isothermal titration calorimetry, was high enough for fibrous assemblies to form at micromolar concentrations. The formation of a fibrous assembly from PZnPFB and PyPFB was visualized by atomic force microscopy and transmission electron microscopy (TEM). When a 1:1 mixture solution of PZnPFB and PyPFB (20 ?M) in toluene was cast onto mica, fibrous assemblies with regular height (ca. 2 nm) were observed. TEM images obtained from 1:1 mixture solution of PZnPFB and PyPFB (0.1 wt %) in toluene clearly showed the formation of nanofibers with a regular diameter of ca. 6 nm. Fluorescence emission measurement of PZnPM indicated efficient intramolecular energy transfer from PZn to the focal PFB or PCu. By the formation of supramolecular coordination polymers, the intramolecular energy transfer changed to intermolecular energy transfer from PZnPM to PyPM. When the nonfluorescent PyPCu was titrated to fluorescent PZnPFB, fluorescence emission from the focal PFB was gradually decreased. By the titration of fluorescent PyPFB to nonfluorescent PZnPCu, fluorescence emission from PFB in PyPFB was gradually increased due to the efficient energy transfer from PZn wings in PZnPCu to PyPFB. PMID:26349620

  14. Mixed ligand coordination polymers with flexible bis-imidazole linker and angular sulfonyldibenzoate: Crystal structure, photoluminescence and photocatalytic activity

    SciTech Connect

    Bisht, Kamal Kumar; Rachuri, Yadagiri; Parmar, Bhavesh; Suresh, Eringathodi

    2014-05-01

    Four ternary coordination polymers (CPs) namely, ([Ni(SDB)(BITMB)(H{sub 2}O)]·H{sub 2}O){sub n} (CP1), ([Cd(SDB)(BITMB) (H{sub 2}O)]·(THF)(H{sub 2}O)){sub n} (CP2), ([Zn{sub 2}(SDB){sub 2}(BITMB)]·(THF){sub 2}){sub n} (CP3) and ([Co{sub 2}(SDB){sub 2}(BITMB)]·(Dioxane){sub 3}){sub n} (CP4) composed of angular dicarboxylate SDB (4,4'-sulfonyldibenzoate) and N-donor BITMB (1,3-bis(imidazol-1-ylmethyl)-2,4,6-trimethyl benzene) have been synthesized by solvothermal reactions and characterized by single crystal X-ray diffraction and other physico-chemical techniques. CP1 possesses one-dimensional ribbon type metal–organic motifs glued together by H-bonds and ??? interactions, whereas CP2–CP4, exhibit non-interpenetrated sql networks supported by weak supramolecular interactions. Structural diversity of these CPs can be attributed to the coordination geometry adopted by the metal nodes, versatile coordination modes of SDB and conformational flexibility of BITMB. Solid state luminescence properties of CP1–CP4 were explored. Photocatalytic performance of all CPs for the decomposition of metanil yellow by dilute hydrogen peroxide in the presence of visible light was also investigated. 25–83% dye removal from aqueous solutions in the presence of CP1–CP4 was observed. - Graphical abstract: Four new ternary transition metal CPs have been hydrothermally prepared and their structural aspects as well as photocatalytic activity for decolourization of metanil yellow (MY) dye have been investigated. - Highlights: • Four ternary coordination polymers containing Ni, Cd, Zn and Co center are prepared. • Crystal structure and thermal stability of all four CPs has been described. • PL and diffuse reflectance spectra of synthesized CPs have also been examined. • Band gap values suggest semiconducting behavior of prepared CPs. • Photocatalytic activity of CPs for oxidative degradation of metanil yellow is studied.

  15. Mixed ligand coordination polymers with flexible bis-imidazole linker and angular sulfonyldibenzoate: Crystal structure, photoluminescence and photocatalytic activity

    NASA Astrophysics Data System (ADS)

    Bisht, Kamal Kumar; Rachuri, Yadagiri; Parmar, Bhavesh; Suresh, Eringathodi

    2014-05-01

    Four ternary coordination polymers (CPs) namely, {[Ni(SDB)(BITMB)(H2O)]·H2O}n (CP1), {[Cd(SDB)(BITMB) (H2O)]·(THF)(H2O)}n (CP2), {[Zn2(SDB)2(BITMB)]·(THF)2}n (CP3) and {[Co2(SDB)2(BITMB)]·(Dioxane)3}n (CP4) composed of angular dicarboxylate SDB (4,4'-sulfonyldibenzoate) and N-donor BITMB (1,3-bis(imidazol-1-ylmethyl)-2,4,6-trimethyl benzene) have been synthesized by solvothermal reactions and characterized by single crystal X-ray diffraction and other physico-chemical techniques. CP1 possesses one-dimensional ribbon type metal-organic motifs glued together by H-bonds and ?⋯? interactions, whereas CP2-CP4, exhibit non-interpenetrated sql networks supported by weak supramolecular interactions. Structural diversity of these CPs can be attributed to the coordination geometry adopted by the metal nodes, versatile coordination modes of SDB and conformational flexibility of BITMB. Solid state luminescence properties of CP1-CP4 were explored. Photocatalytic performance of all CPs for the decomposition of metanil yellow by dilute hydrogen peroxide in the presence of visible light was also investigated. 25-83% dye removal from aqueous solutions in the presence of CP1-CP4 was observed.

  16. Synthesis and characterization of different zinc(II) oxide nano-structures from two new zinc(II)-Quinoxaline coordination polymers

    NASA Astrophysics Data System (ADS)

    Molaei, Fatemeh; Bigdeli, Fahime; Morsali, Ali; Joo, Sang Woo; Bruno, Giuseppe; Rudbari, Hadi Amiri

    2015-09-01

    Two new zinc(II) coordination polymers, [Zn(Quinoxaline)(NO3)2(H2O)2]n?Quinoxaline·H2O (1) and [Zn(Quinoxaline)2(Br)2]n (2), Quinoxaline = Benzopyrazine, have been synthesized and characterized by IR spectroscopy. Compounds 1 and 2 were structurally characterized by single crystal X-ray diffraction and are one-dimensional coordination polymers with coordination environment of octahedral and tetrahedral respectively. Nanostructures of zinc(II) oxide were obtained by thermolyses of compound 1 in oleic acid, calcination of compound 1 at 500 °C under air atmosphere and sol-gel processes. Also, nanopowders of zinc(II) oxide were obtained by calcination of compound 2 at 450 and 550 °C. The nanomaterials were characterized by scanning electron microscopy and X-ray powder diffraction (XRD). The thermal stability of compounds 1 and 2 both their bulk were studied by thermo-gravimetric (TGA) and differential thermal analyses (DTA). This study demonstrates the coordination polymers may be suitable precursors for the preparation of nanoscale materials.

  17. DOI: 10.1002/ejic.201000555 Flexible and Redox-Active Coordination Polymer: Control of the Network

    E-print Network

    Paik Suh, Myunghyun

    FULL PAPER DOI: 10.1002/ejic.201000555 Flexible and Redox-Active Coordination Polymer: Control*[a] Keywords: Coordination polymers / Flexible networks / Macrocyles / Palladium / Nickel The coordination polymer {[Ni(C20H32N8)]2[TCM]}·5DMF· 8H2O (1) has been assembled from a NiII macrocyclic com- plex

  18. Nanoscale coordination polymers exhibiting luminescence properties and NMR relaxivity

    NASA Astrophysics Data System (ADS)

    Chelebaeva, Elena; Larionova, Joulia; Guari, Yannick; Ferreira, Rute A. S.; Carlos, Luis D.; Trifonov, Alexander A.; Kalaivani, Thangavel; Lascialfari, Alessandro; Guérin, Christian; Molvinger, Karine; Datas, Lucien; Maynadier, Marie; Gary-Bobo, Magali; Garcia, Marcel

    2011-03-01

    This article presents the first example of ultra-small (3-4 nm) magneto-luminescent cyano-bridged coordination polymer nanoparticles Ln0.333+Gdx3+/[Mo(CN)8]3- (Ln = Eu (x = 0.34), Tb (x = 0.35)) enwrapped by a natural biocompatible polymer chitosan. The aqueous colloidal solutions of these nanoparticles present a luminescence characteristic of the corresponding lanthanides (5D0 --> 7F0-4 (Eu3+) or the 5D4 --> 7F6-2 (Tb3+)) under UV excitation and a green luminescence of the chitosan shell under excitation in the visible region. Magnetic Resonance Imaging (MRI) efficiency, i.e. the nuclear relaxivity, measurements performed for Ln0.333+Gdx3+/[Mo(CN)8]3- nanoparticles show r1p and r2p relaxivities slightly higher than or comparable to the ones of the commercial paramagnetic compounds Gd-DTPA® or Omniscan® indicating that our samples may potentially be considered as a positive contrast agent for MRI. The in vitro studies performed on these nanoparticles show that they maybe internalized into human cancer and normal cells and well detected by fluorescence at the single cell level. They present high stability even at low pH and lack of cytotoxicity both in human cancer and normal cells.This article presents the first example of ultra-small (3-4 nm) magneto-luminescent cyano-bridged coordination polymer nanoparticles Ln0.333+Gdx3+/[Mo(CN)8]3- (Ln = Eu (x = 0.34), Tb (x = 0.35)) enwrapped by a natural biocompatible polymer chitosan. The aqueous colloidal solutions of these nanoparticles present a luminescence characteristic of the corresponding lanthanides (5D0 --> 7F0-4 (Eu3+) or the 5D4 --> 7F6-2 (Tb3+)) under UV excitation and a green luminescence of the chitosan shell under excitation in the visible region. Magnetic Resonance Imaging (MRI) efficiency, i.e. the nuclear relaxivity, measurements performed for Ln0.333+Gdx3+/[Mo(CN)8]3- nanoparticles show r1p and r2p relaxivities slightly higher than or comparable to the ones of the commercial paramagnetic compounds Gd-DTPA® or Omniscan® indicating that our samples may potentially be considered as a positive contrast agent for MRI. The in vitro studies performed on these nanoparticles show that they maybe internalized into human cancer and normal cells and well detected by fluorescence at the single cell level. They present high stability even at low pH and lack of cytotoxicity both in human cancer and normal cells. Electronic supplementary information (ESI) available: TEM images and size distribution histograms, IR and emission spectra, diffraction pattern and HRTEM coupled EDX analysis. See DOI: 10.1039/c0nr00709a

  19. Analysis of one-dimensional barcode

    NASA Astrophysics Data System (ADS)

    Wang, Ynjiun P.; Pavlidis, Theo; Swartz, Jerome

    1991-02-01

    The information content and error tolerance analysis for several one dimensional bar codes is presented. A method which applies coding theory to design an bar code under a given error tolerance is presented.

  20. One-dimensional gas of hard needles

    E-print Network

    Kardar, Mehran

    We study a one-dimensional gas of needlelike objects as a testing ground for a formalism that relates the thermodynamic properties of “hard” potentials to the probabilities for contacts between particles. Specifically, we ...

  1. One-Dimensional Czedli-Type Islands

    ERIC Educational Resources Information Center

    Horvath, Eszter K.; Mader, Attila; Tepavcevic, Andreja

    2011-01-01

    The notion of an island has surfaced in recent algebra and coding theory research. Discrete versions provide interesting combinatorial problems. This paper presents the one-dimensional case with finitely many heights, a topic convenient for student research.

  2. Pose estimation for one-dimensional object with general motion

    NASA Astrophysics Data System (ADS)

    Liu, Jinbo; Song, Ge; Zhang, Xiaohu

    2014-11-01

    Our primary interest is in real-time one-dimensional object's pose estimation. In this paper, a method to estimate general motion one-dimensional object's pose, that is, the position and attitude parameters, using a single camera is proposed. Centroid-movement is necessarily continuous and orderly in temporal space, which means it follows at least approximately certain motion law in a short period of time. Therefore, the centroid trajectory in camera frame can be described as a combination of temporal polynomials. Two endpoints on one-dimensional object, A and B, at each time are projected on the corresponding image plane. With the relationship between A, B and centroid C, we can obtain a linear equation system related to the temporal polynomials' coefficients, in which the camera has been calibrated and the image coordinates of A and B are known. Then in the cases that object moves continuous in natural temporal space within the view of a stationary camera, the position of endpoints on the one-dimensional object can be located and also the attitude can be estimated using two end points. Moreover the position of any other point aligned on one-dimensional object can also be solved. Scene information is not needed in the proposed method. If the distance between the endpoints is not known, a scale factor between the object's real positions and the estimated results will exist. In order to improve the algorithm's performance from accuracy and robustness, we derive a pain of linear and optimal algorithms. Simulations' and experiments' results show that the method is valid and robust with respect to various Gaussian noise levels. The paper's work contributes to making self-calibration algorithms using one-dimensional objects applicable to practice. Furthermore, the method can also be used to estimate the pose and shape parameters of parallelogram, prism or cylinder objects.

  3. Factorizations of one-dimensional classical systems

    SciTech Connect

    Kuru, Senguel; Negro, Javier

    2008-02-15

    A class of one-dimensional classical systems is characterized from an algebraic point of view. The Hamiltonians of these systems are factorized in terms of two functions that together with the Hamiltonian itself close a Poisson algebra. These two functions lead directly to two time-dependent integrals of motion from which the phase motions are derived algebraically. The systems so obtained constitute the classical analogues of the well known factorizable one-dimensional quantum mechanical systems.

  4. Different geometrical arrangements in carboxylate coordination polymers of flexible dicarboxylic acid

    SciTech Connect

    Deka, Himangshu; Sarma, Rupam; Kumari, Satchi; Khare, Alika; Baruah, Jubaraj B.

    2011-07-15

    Dicarboxylate coordination polymers (1-5) of Mn(II), Ni(II), Cu(II), Zn(II) and Cd(II), respectively, derived from (7-carboxymethoxy-naphthalen-2-yloxy)-acetic acid (L{sub 1}H{sub 2}) are synthesized and characterized. Depending on the coordination sites around the metal centers and coordination mode of the ligand, dimensionality of these polymers varies. The dicarboxylates adopt three spatial orientations: in-plane linear coordination, out-of-plane cis coordination and out-of-plane trans coordination mode. Both the cis and trans out-of-plane coordination modes are found to exist only if the ancillary ligand pyridine is coordinated to the metal ion. When the aquoligand coordinates the in-plane linear coordination mode of L{sub 1} predominates. The coordination polymers 4 and 5 show photoluminescence in solution. The dicarboxylate of (5-carboxymethoxy-naphthalen-1-yloxy)-acetic acid (L{sub 2}H{sub 2}) does not form coordination polymer under ambient conditions, but prefers to remain as uncoordinated anion providing hydrophobic confinement to hexa-aquometal(II) cation. Compound 3 crystallizes in P2{sub 1} space group and it shows broadband ultra-violet fluorescence centered at 352.9 nm on focusing 632.8 nm He:Ne laser. - Graphical abstract: Different geometrical arrangements in coordination polymers derived from (7-carboxymethoxy-naphthalen-2-yloxy)-acetic acid of metal ions Mn(II), Ni(II), Cu(II), Zn(II) and Cd(II) are presented. The (5-carboxymethoxy-naphthalen-1-yloxy)-acetic acid led to hexa-aquo cadmium(II) dicarboxylate. Highlights: > Structural and spectroscopic characterizations of five dicarboxylate coordination polymers of (7-carboxymethoxy-naphthalen-2-yloxy)-acetic acid with different metal ions are presented. > Different geometrical arrangements of coordination polymers stabilized in solid state are described. > Photoluminescence properties of the polymers are shown. > NLO property of a copper coordination polymer is described.

  5. Polymer complexes. LX. Supramolecular coordination and structures of N(4-(acrylamido)-2-hydroxybenzoic acid) polymer complexes

    NASA Astrophysics Data System (ADS)

    Ghoneim, M. M.; El-Sonbati, A. Z.; El-Bindary, A. A.; Diab, M. A.; Serag, L. S.

    2015-04-01

    A number of novel polymer complexes of various anions of copper(II), cobalt(II), nickel(II) and uranyl(II) with N(4-(acrylamido)-2-hydroxy benzoic acid) (ABH) have been synthesized and characterized by elemental analysis, IR, 1H NMR, magnetic susceptibility measurements, electronic spin resonance, vibrational spectra and thermal analysis. The molecular structures of the ligand are optimized theoretically and the quantum chemical parameters are calculated. Tentative structures for the polymeric metal complexes due to their potential application are also suggested. The IR data exhibit the coordination of ONO2/OAc/SO4 with the metal ions in the polymeric metal complex. Vibrational spectra indicate coordination of carboxylate oxygen and phenolic OH of the ligand giving a MO4 square planar chromophore. Ligand field ESR spectra support square planar geometry around Cu(II). The thermal decomposition of the polymer complexes were discussed in relation to structure, and the thermodynamic parameters of the decomposition stages were evaluated applying Coast-Redfern and Horowitz-Metzger methods.

  6. Polymer complexes. LX. Supramolecular coordination and structures of N(4-(acrylamido)-2-hydroxybenzoic acid) polymer complexes.

    PubMed

    Ghoneim, M M; El-Sonbati, A Z; El-Bindary, A A; Diab, M A; Serag, L S

    2015-04-01

    A number of novel polymer complexes of various anions of copper(II), cobalt(II), nickel(II) and uranyl(II) with N(4-(acrylamido)-2-hydroxy benzoic acid) (ABH) have been synthesized and characterized by elemental analysis, IR, 1H NMR, magnetic susceptibility measurements, electronic spin resonance, vibrational spectra and thermal analysis. The molecular structures of the ligand are optimized theoretically and the quantum chemical parameters are calculated. Tentative structures for the polymeric metal complexes due to their potential application are also suggested. The IR data exhibit the coordination of ONO2/OAc/SO4 with the metal ions in the polymeric metal complex. Vibrational spectra indicate coordination of carboxylate oxygen and phenolic OH of the ligand giving a MO4 square planar chromophore. Ligand field ESR spectra support square planar geometry around Cu(II). The thermal decomposition of the polymer complexes were discussed in relation to structure, and the thermodynamic parameters of the decomposition stages were evaluated applying Coast-Redfern and Horowitz-Metzger methods. PMID:25589393

  7. Crystal structure, infrared spectra and luminescence of a 1D Cd coordination polymer with 4-nitrophthalic acid and 1,10-phenanthroline monohydrate ligands

    NASA Astrophysics Data System (ADS)

    Han, Li-Juan; Kong, Ya-Jie; Sheng, Ning

    2015-01-01

    A new one-dimensional (1D) coordination polymer, [Cd(NPTA)(1,10-phen)(H2O)] n ( 1) (H2NPTA = 4-nitrophthalic acid; 1,10-phen = 1,10-phenanthroline monohydrate), has been synthesized under hydrothermal conditions and characterized by elemental analysis, single-crystal X-ray diffraction, solid state emission spectra, FT-IR spectra, and thermogravimetric analyses. The compound belongs to triclinic system with space group , and exhibits a one-dimensional linear chain. Each Cd with a strongly distorted octahedral coordination geometry is six-coordinated by two N atoms from one 1,10-phenanthroline ligand, three O atoms from two carboxylate groups of two different NPTA2- ligands and one O atoms from lattice water. Layer supramolecular architecture is formed by medium ?-? stacking interactions between two neighboring phenanthroline rings from two independent linear chains. Studies on luminescent property of 1 exhibit the solid state emission originating from an intra ligand ? ? ?* transition of NPTA2- ligand.

  8. One-dimensional Gromov minimal filling problem

    SciTech Connect

    Ivanov, Alexandr O; Tuzhilin, Alexey A

    2012-05-31

    The paper is devoted to a new branch in the theory of one-dimensional variational problems with branching extremals, the investigation of one-dimensional minimal fillings introduced by the authors. On the one hand, this problem is a one-dimensional version of a generalization of Gromov's minimal fillings problem to the case of stratified manifolds. On the other hand, this problem is interesting in itself and also can be considered as a generalization of another classical problem, the Steiner problem on the construction of a shortest network connecting a given set of terminals. Besides the statement of the problem, we discuss several properties of the minimal fillings and state several conjectures. Bibliography: 38 titles.

  9. Black holes are one-dimensional

    E-print Network

    Bekenstein, J D; Bekenstein, Jacob D.; Mayo, Avraham E.

    2001-01-01

    The holographic principle has revealed that physical systems in 3-D space, black holes included, are basically two-dimensional as far as their information content is concerned. This conclusion is complemented by one sketched here: as far as entropy or information flow is concerned, a black hole behaves as a one-dimensional channel. We define a channel in flat spacetime in thermodynamic terms, and contrast it with common entropy emitting systems. A black hole is more like the former: its entropy output is related to the emitted power as it would be for a one-dimensional channel, and disposal of an information stream down a black hole is limited by the power invested in the same way as for a one-dimensional channel.

  10. One-dimensional magnetism in copper phthalocyanine

    NASA Astrophysics Data System (ADS)

    Lee, S.; Yudkowsky, M.; Halperin, W. P.; Ogawa, M. Y.; Hoffman, B. M.

    1987-04-01

    Measurements of the proton spin-lattice relaxation rate, T-11, reveal that the organic insulator copper phthalocyanine Cu(PC) is a highly one-dimensional Heisenberg system. T-11 diverges as ?-1/2 down to 11.4 MHz without evidence of cutoff. It was found that ||J/kB||=0.286 K with the ratio ||J/J'||>=6×103, where J and J' are the intrachain and interchain exchange interactions, indicating that Cu(PC) is an excellent model one-dimensional Heisenberg magnet.

  11. Observing solitons in one dimensional magnetic systems

    SciTech Connect

    Reiter, G.

    1981-01-01

    Classical models of one dimensional magnetic systems show that in addition to the linear spin wave excitations, there should exist localized, large amplitude excitations, that can move along the chains while retaining their integrity. It is expected that these excitations, solitons, exist in real materials. The progress that has been made to date in observing solitons in one dimensional magnets by means of neutron scattering, and the difficulties that still remain in unambiguously identifying the soliton contributions to S(q,..omega..) are discussed.

  12. Finite-temperature second-order many-body perturbation and Hartree–Fock theories for one-dimensional solids: An application to Peierls and charge-density-wave transitions in conjugated polymers

    SciTech Connect

    He, Xiao; State Key Laboratory of Precision Spectroscopy and Department of Physics, Institute of Theoretical and Computational Science, East China Normal University, Shanghai 200062 ; Ryu, Shinsei; Hirata, So; CREST, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012

    2014-01-14

    Finite-temperature extensions of ab initio Gaussian-basis-set spin-restricted Hartree–Fock (HF) and second-order many-body perturbation (MP2) theories are implemented for infinitely extended, periodic, one-dimensional solids and applied to the Peierls and charge-density-wave (CDW) transitions in polyyne and all-trans polyacetylene. The HF theory predicts insulating CDW ground states for both systems in their equidistant structures at low temperatures. In the same structures, they turn metallic at high temperatures. Starting from the “dimerized” low-temperature equilibrium structures, the systems need even higher temperatures to undergo a Peierls transition, which is accompanied by geometric as well as electronic distortions from dimerized to non-dimerized forms. The conventional finite-temperature MP2 theory shows a sign of divergence in any phase at any nonzero temperature and is useless. The renormalized finite-temperature MP2 (MP2R) theory is divergent only near metallic electronic structures, but is well behaved elsewhere. MP2R also predicts CDW and Peierls transitions occurring at two different temperatures. The effect of electron correlation is primarily to lower the Peierls transition temperature.

  13. Heat conduction in one dimensional chains

    E-print Network

    Bambi Hu; Baowen LI; Hong Zhao

    1997-12-05

    We study numerically the thermal conductivity in several different one dimensional chains. We show that the phonon-lattice interaction is the main ingredient of the Fourier heat law. Our argument provides a rather satisfactory explanation to all existing numerical results concerning this problem.

  14. One-Dimensional Wavefront Sensor Analysis

    Energy Science and Technology Software Center (ESTSC)

    1996-04-25

    This software analyzes one-dimensional wavefront sensor data acquired with any of several data acquisition systems. It analyzes the data to determine centroids, wavefront slopes and overall wavefront error. The data can be displayed in many formats, with plots of various parameters vs time and position, including computer generated movies. Data can also be exported for use by other programs.

  15. One-Dimensional Oscillator in a Box

    ERIC Educational Resources Information Center

    Amore, Paolo; Fernandez, Francisco M.

    2010-01-01

    We discuss a quantum-mechanical model of two particles that interact by means of a harmonic potential and are confined to a one-dimensional box with impenetrable walls. We apply perturbation theory to the cases of different and equal masses and analyse the symmetry of the states in the latter case. We compare the approximate perturbation results…

  16. Compound structure one-dimensional photonic crystal

    E-print Network

    Wu, Xiang-Yao; Liu, Xiao-Jing; Liang, Yu; Wang, Zhi-Guo; Fang, Yun-Tuan

    2015-01-01

    In this paper, we have proposed a new compound structure one-dimensional photonic crystal, which include series connection, parallel connection and positive and negative feedback compound structure photonic crystal. We have studied their transmission characteristics and obtained some new results, which should be help to design new type optical devices, such as optical amplifier, photonic crystal laser and so on.

  17. Functional One-Dimensional Lipid Bilayers on Carbon Nanotube Templates

    SciTech Connect

    Artyukhin, A; Shestakov, A; Harper, J; Bakajin, O; Stroeve, P; Noy, A

    2004-07-23

    We present one-dimensional (1-D) lipid bilayer structures that integrate carbon nanotubes with a key biological environment-phospholipid membrane. Our structures consist of lipid bilayers wrapped around carbon nanotubes modified with a hydrophilic polymer cushion layer. Despite high bilayer curvature, the lipid membrane maintains its fluidity and can sustain repeated damage-recovery cycles. We also present the first evidence of spontaneous insertion of pore-forming proteins into 1-D lipid bilayers. These structures could lead to the development of new classes of biosensors and bioelectronic devices.

  18. A mixed valent heterometallic Cu(II)/Na(I) coordination polymer with sodium-phenyl bonds.

    PubMed

    Datta, Amitabha; Das, Kuheli; Massera, Chiara; Clegg, Jack K; Sinha, Chittaranjan; Huang, Jui-Hsien; Garribba, Eugenio

    2014-04-14

    A mixed valent heterometallic Cu(II)/Na(I) coordination polymer (1) is generated by the reaction of a Schiff base ligand, (6,6'-(1E,1'E)-(2-hydroxypropane-1,3-diyl)bis(azan-1-yl-1-ylidene)bis(methan-1-yl-1-ylidene)bis(2-methoxyphenol)) with copper(II) acetate and sodium perchlorate. In addition to the presence of alcohol oxygen-sodium coordination bonds, the single crystal X-ray structure reveals that the 1D coordination polymer is stabilised by the formation of phenyl-sodium ?2-bonds, face-to-face ?-? contacts and Cu-? interactions. PMID:24549373

  19. Transient One-dimensional Pipe Flow Analyzer

    SciTech Connect

    1986-04-08

    TOPAZ-SNLL, the Transient One- dimensional Pipe flow AnalyZer code, is a user-friendly computer program for modeling the heat transfer, fluid mechanics, and thermodynamics of multi-species gas transfer in arbitrary arrangements of pipes, valves, vessels, and flow branches. Although the flow conservation equations are assumed to be one-dimensional and transient, multidimensional features of internal fluid flow and heat transfer may be accounted for using the available quasi-steady flow correlations (e.g., Moody friction factor correlation and various form loss and heat transfer correlations). Users may also model the effects of moving system boundaries such as pistons, diaphragms, and bladders. The features of fully compressible flow are modeled, including the propagation of shocks and rarefaction waves, as well as the establishment of multiple choke points along the flow path.

  20. The one dimensional Coulomb lattice fluid capacitor

    E-print Network

    Vincent Demery; David S. Dean; Thomas C. Hammant; Ronald R. Horgan; Rudolf Podgornik

    2012-06-21

    The one dimensional Coulomb lattice fluid in a capacitor configuration is studied. The model is formally exactly soluble via a transfer operator method within a field theoretic representation of the model. The only interactions present in the model are the one dimensional Coulomb interaction between cations and anions and the steric interaction imposed by restricting the maximal occupancy at any lattice site to one particle. Despite the simplicity of the model, a wide range of intriguing physical phenomena arise, some of which are strongly reminiscent of those seen in experiments and numerical simulations of three dimensional ionic liquid based capacitors. Notably we find regimes where over-screening and density oscillations are seen near the capacitor plates. The capacitance is also shown to exhibit strong oscillations as a function of applied voltage. It is also shown that the corresponding mean field theory misses most of these effects. The analytical results are confirmed by extensive numerical simulations.

  1. Transient One-dimensional Pipe Flow Analyzer

    Energy Science and Technology Software Center (ESTSC)

    1986-04-08

    TOPAZ-SNLL, the Transient One- dimensional Pipe flow AnalyZer code, is a user-friendly computer program for modeling the heat transfer, fluid mechanics, and thermodynamics of multi-species gas transfer in arbitrary arrangements of pipes, valves, vessels, and flow branches. Although the flow conservation equations are assumed to be one-dimensional and transient, multidimensional features of internal fluid flow and heat transfer may be accounted for using the available quasi-steady flow correlations (e.g., Moody friction factor correlation and variousmore »form loss and heat transfer correlations). Users may also model the effects of moving system boundaries such as pistons, diaphragms, and bladders. The features of fully compressible flow are modeled, including the propagation of shocks and rarefaction waves, as well as the establishment of multiple choke points along the flow path.« less

  2. Diffraction from quasi-one-dimensional crystals

    SciTech Connect

    Vukovic, T.; Milosevic, I.; Damnjanovic, M.

    2009-04-15

    General expressions of diffraction intensity distribution of quasi-one-dimensional crystals are evaluated within kinematical approximation. In order to gain the generality, diffraction intensity has been derived for each of the fifteen conformation classes. Characteristic features of the diffraction patterns are discussed and it is shown how the symmetry can be fully determined from the diffraction intensity distribution. General results are tabulated and their application is illustrated on the (10,10) molybdenum disulfide nanotube.

  3. Momentum Dynamics of One Dimensional Quantum Walks

    E-print Network

    Ian Fuss; Langord B. White; Peter J. Sherman; Sanjeev Naguleswaran

    2006-05-24

    We derive the momentum space dynamic equations and state functions for one dimensional quantum walks by using linear systems and Lie group theory. The momentum space provides an analytic capability similar to that contributed by the z transform in discrete systems theory. The state functions at each time step are expressed as a simple sum of three Chebyshev polynomials. The functions provide an analytic expression for the development of the walks with time.

  4. Highly luminescent and triboluminescent coordination polymers assembled from lanthanide ?-diketonates and aromatic bidentate O-donor ligands.

    PubMed

    Eliseeva, Svetlana V; Pleshkov, Dmitry N; Lyssenko, Konstantin A; Lepnev, Leonid S; Bünzli, Jean-Claude G; Kuzmina, Natalia P

    2010-10-18

    The reaction of hydrated lanthanide hexafluoroacetylacetonates, [Ln(hfa)(3)(H(2)O)(2)], with 1,4-disubstituted benzenes afforded a new series of one-dimensional coordination polymers [Ln(hfa)(3)(Q)](?), where Ln = Eu, Gd, Tb, and Lu and Q = 1,4-diacetylbenzene (acbz), 1,4-diacetoxybenzene (acetbz), or 1,4-dimethyltherephtalate (dmtph). X-ray single crystal analyses reveal [Ln(hfa)(3)(acbz)](?) (Ln = Eu, Gd, Tb) consisting of zigzag polymeric chains with Ln-Ln-Ln angles equal to 128°, while the arrays are more linear in [Eu(hfa)(3)(acetbz)](?) and [Eu(hfa)(3)(dmtph)](?), with Ln-Ln-Ln angles of 165° and 180°, respectively. In all structures, Ln(III) ions are 8-coordinate and lie in distorted square-antiprismatic environments. The coordination polymers are thermally stable up to 180-210 °C under a nitrogen atmosphere. Their volatility has been tested in vacuum sublimation experiments at 200-250 °C and 10(-2) Torr: the metal-organic frameworks with acetbz and dmtph can be quantitatively sublimed, while [Ln(hfa)(3)(acbz)](?) undergoes thermal decomposition. The triplet state energies of the ancillary ligands, 21,600 (acetbz), 22,840 (acbz), and 24,500 (dmtph) cm(-1), lie in an ideal range for sensitizing the luminescence of Eu(III) and/or Tb(III). As a result, all of the [Ln(hfa)(3)(Q)](?) polymers display bright red or green luminescence due to the characteristic (5)D(0) ? (7)F(J) (J = 0-4) or (5)D(4) ? (7)F(J) (J = 6-0) transitions, respectively. Absolute quantum yields reach 51(Eu) and 56(Tb) % for the frameworks built from dmtph. Thin films of [Eu(hfa)(3)(Q)](?) with 100-170 nm thickness can be obtained by thermal evaporation (P < 3 × 10(-5) Torr, 200-250 °C). They are stable over a long period of time, and their photophysical parameters are similar to those of the bulk samples so that their use as active materials in luminescent devices can be envisaged. Mixtures of [Ln(hfa)(3)(dmpth)](?) with Ln = Eu and Tb yield color-tunable microcrystalline materials from red to green. Finally, the crystalline samples exhibit strong triboluminescence, which could be useful in the design of pressure and/or damage detection probes. PMID:20849088

  5. Dimensional modulation and magnetic properties of triazole- and bis(triazole)-based copper(II) coordination polymers tuned by aromatic polycarboxylates

    SciTech Connect

    Zhang, Ju-Wen; Zhao, Wei; Lu, Qi-Lin; Luan, Jian; Qu, Yun; Wang, Xiu-Li

    2014-04-01

    Five new metal–organic coordination polymers ([Cu{sub 3}(?{sub 2}-OH){sub 2}(atrz){sub 2}(nph){sub 2}(H{sub 2}O){sub 2}]·2H{sub 2}O){sub n} (1), ([Cu{sub 2}(?{sub 3}-OH)(atrz)(1,2,4-btc)]·2H{sub 2}O){sub n} (2), ([Cu{sub 2}(?{sub 3}-OH)(atrz)(1,2,4-btc)(H{sub 2}O)]·H{sub 2}O){sub n} (3), [Cu(dth){sub 0.5}(nph)(H{sub 2}O)]{sub n} (4) and [Cu(dth)(Hnip){sub 2}]{sub n} (5) [atrz=4-amino-1,2,4-triazole, dth=N,N'-di(4H-1,2,4-triazole)hexanamide, H{sub 2}nph=3-nitrophthalic acid, 1,2,4-H{sub 3}btc=1,2,4-benzenetricarboxylic acid and H{sub 2}nip=5-nitroisophthalic acid] were hydrothermally synthesized and structurally characterized. Polymer 1 shows a one-dimensional (1D) chain. Polymers 2 and 3 exhibit similar tetranuclear Cu{sup II}{sub 4} cluster-based three-dimensional (3D) frameworks with the same components. Polymer 4 possesses a 3D framework with a 4{sup 12}·6{sup 3}-pcu topology. Polymer 5 displays a 3D framework with a 4{sup 4}·6{sup 10}·8-mab topology. The magnetic properties of 1–4 were investigated. - Graphical abstract: Five triazole-based copper(II) polymers modulated by polycarboxylates were synthesized. Bis-triazole-bis-amide ligand and polycarboxylates play important roles in tuning dimensionality of polymers. Magnetic properties of polymers were investigated. - Highlights: • Five triazole- and bis(triazole)-based copper(II) coordination polymers tuned by aromatic polycarboxylates were obtained. • The aromatic polycarboxylates have an important influence on the dimensionality of five polymers. • The magnetic properties of four polymers were investigated.

  6. Synthesis and structural characterization of new bismuth (III) nano coordination polymer: A precursor to produce pure phase nano-sized bismuth (III) oxide

    NASA Astrophysics Data System (ADS)

    Hanifehpour, Younes; Mirtamizdoust, Babak; Hatami, Masoud; Khomami, Bamin; Joo, Sang Woo

    2015-07-01

    A novel bismuth (III) nano coordination polymer, {[Bi (pcih)(NO3)2]?MeOH}n (1), ("pcih" is the abbreviations of 2-pyridinecarbaldehyde isonicotinoylhydrazoneate) were synthesized by a sonochemical method. The new nano-structure was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray powder diffraction, elemental analyses and IR spectroscopy. Single crystalline material was obtained using a heat gradient applied to a solution of the reagents. Compound 1 was structurally characterized by single crystal X-ray diffraction. The determination of the structure by single crystal X-ray crystallography shows that the complex forms a zig-zag one dimensional polymer in the solid state and the coordination number of BiIII ions is seven, (BiN3O4), with three N-donor and one O-donor atoms from two "pcih" and three O-donors from nitrate anions. It has a hemidirected coordination sphere. The supramolecular features in these complexes are guided and controlled by weak directional intermolecular interactions. The chains interact with each other through ?-? stacking interactions creating a 3D framework. After thermolysis of 1 at 230 °C with oleic acid, pure phase nano-sized bismuth (III) oxide was produced. The morphology and size of the prepared Bi2O3 samples were further observed using SEM.

  7. pH- and mol-ratio dependent formation of zinc(II) coordination polymers with iminodiacetic acid: synthesis, spectroscpic, crystal structure and thermal studies

    PubMed Central

    Ni, Lu-Bin; Zhang, Rong-Hua; Liu, Qiong-Xin; Xia, Wen-Sheng; Wang, Hongxin; Zhou, Zhao-Hui

    2009-01-01

    Three novel zinc coordination polymers (NH4)n[Zn(Hida)Cl2]n (1), [Zn(ida)(H2O)2]n (2), [Zn(Hida)2]n·4nH2O (3) (H2ida = iminodiacetic acid) and a monomeric complex [Zn(ida)(phen)(H2O)]·2H2O (4) (phen=1,10-phenanthroline) have been synthesized and characterized by X-ray diffraction methods. 1 and 2 form one-dimensional (1-D) chain structures, whereas 3 exhibits a three-dimensional (3-D) diamondoid framework with an open channel. The mononuclear complex 4 is extended into a 3-D supramolecular architecture through hydrogen bonds and ?-? stacking. Interestingly, cyclic nonplanar tetrameric water clusters are observed that encapsulated in the 3-D lattice of 4. Based on 1H and 13C NMR observations, there is obvious coordination of complex 2 in solution, while 1 and 3 decompose into free iminodiacetate ligand. Monomer [Zn(ida)(H2O)3] (5) is considered as a possible discrete species from 2. These coordination polymers can serve as good molecular precursors for zinc oxide. PMID:20161370

  8. Nonlinear one-dimensional guided wedge waves

    NASA Astrophysics Data System (ADS)

    Lomonosov, Alexey M.; Pupyrev, Pavel D.; Hess, Peter; Mayer, Andreas P.

    2015-07-01

    The experimental observation of an efficient second-order nonlinearity with dominating frequency upconversion is reported for one-dimensional (1D) guided elastic waves localized at solid edges. These 1D acoustic wedge waves are a fundamental type of elastic wave with a phase velocity below that of surface and bulk waves and no coupling to them. Acoustic pulses, showing steepening, narrowing, and spiking to shocklike profiles, were generated and detected by a laser-based pump-probe setup. Shock formation is described by a nonlinear evolution equation, which allows the characteristic features of 1D guided shock waves to be predicted that differ from their bulk and surface analogs.

  9. One-dimensional ZnO nanostructures.

    PubMed

    Jayadevan, K P; Tseng, T Y

    2012-06-01

    The wide-gap semiconductor ZnO with nanostructures such as nanoparticle, nanorod, nanowire, nanobelt, nanotube has high potential for a variety of applications. This article reviews the fundamentals of one-dimensional ZnO nanostructures, including processing, structure, property, application and their processing-microstructure-property correlation. Various fabrication methods of the ZnO nanostructures including vapor-liquid-solid process, vapor-solid growth, solution growth, solvothermal growth, template-assisted growth and self-assembly are introduced. The characterization and properties of the ZnO nanostructures are described. The possible applications of these nanostructures are also discussed. PMID:22905484

  10. Three new homochiral coordination polymers involving two three-dimensional structural architectures: Syntheses, structures and magnetic properties

    SciTech Connect

    Chao, Tzu-Ling; Yang, Chen-I.

    2014-03-15

    The preparations and properties of three new homochiral three-dimensional (3D) coordination polymers, [M(D-cam)(pyz)(H{sub 2}O){sub 2}]{sub n} (M=Co (1) and Ni (2); D-H{sub 2}cam=(+) D-camphoric acid; pyz=pyrazine) and [Mn{sub 2}(D-cam){sub 2}(H{sub 2}O){sub 2}] (3), under solvothermal conditions is described. Single-crystal X-ray diffraction analyses revealed that all of compounds are homochiral 3D structure. 1 and 2 are isostructural and crystallize in the trigonal space group P3{sub 2}21, while 3 crystallizes in monoclinic space group P2{sub 1}. The structure of 1 and 2 consists of metal-D-cam helical chains which are pillared with pyrazine ligands into a 3D framework structure and 3 features a 3D homochiral framework involving one-dimensional manganese-carboxylate chains that are aligned parallel to the b axis. Magnetic susceptibility data of all compounds were collected. The findings indicate that ?{sub 2}-pyrazine dominate weak antiferromagnetic coupling within 1 and 2, while 3 exhibits antiferromagnetic behavior through the carboxylate groups of D-cam ligand. -- Graphical abstract: The preparations and properties of three new homochiral three-dimensional (3D) coordination polymers, [M(D-cam)(pyz)(H{sub 2}O){sub 2}]{sub n} (M=Co (1) and Ni (2); D-H{sub 2}cam=(+) D-camphoric acid; pyz=pyrazine) and [Mn{sub 2}(D-cam){sub 2}(H{sub 2}O){sub 2}] (3), under solvothermal conditions is described. Single-crystal X-ray diffraction analyses revealed that all of compounds are homochiral 3D structure. 1 and 2 are isostructural and crystallize in the trigonal space group P3{sub 2}21, while 3 crystallizes in monoclinic space group P2{sub 1}. The structure of 1 and 2 consists of metal-D-cam helical chains which are pillared with pyrazine ligands into a 3D framework structure and 3 features a 3D homochiral framework involving one-dimensional manganese-carboxylate chains that are aligned parallel to the b axis. Magnetic susceptibility data of all compounds were collected. The findings indicate that ?{sub 2}-pyrazine dominate weak antiferromagnetic coupling within 1 and 2, while 3 exhibits antiferromagnetic behavior through the carboxylate groups of D-cam ligand. Highlights: • Three homochiral 3D coordination polymers were synthesized. • 1 and 2 are 3D structure with metal-D-cam helical chains pillared by pyrazine. • 3 shows a 3D homochiral framework involving 1D manganese-carboxylate chains. • Magnetic data analysis indicates that 1–3 exhibit weak antiferromagnetic coupling.

  11. Interweaving 3D network with double helical tubes filled by 1D coordination polymer chains.

    PubMed

    Yang, E; Zhang, Jian; Li, Zhao-Ji; Gao, Song; Kang, Yao; Chen, Yu-Biao; Wen, Yi-Hang; Yao, Yuan-Gen

    2004-10-18

    The hydrothermal reaction of mellitic acid, 4,4'-bipydine, and Cu(CH(3)COO)(2).H(2)O gave rise to a novel 3D supramolecular architecture interpenetrated by three types of coordination polymer motifs. Two independent [[Cu(2)(mellitate)(4,4'-bpy)(H(2)O)(2)](2)(-)] 3D polymers incorporating helical substructures were interwoven into a 3D network with double-stranded helical tubes that host 1D linear polymers [Cu(4,4'-bpy)(H(2)O)(4)](2+)](n). PMID:15476343

  12. Control of hierarchical polymer mechanics with bioinspired metal-coordination dynamics.

    PubMed

    Grindy, Scott C; Learsch, Robert; Mozhdehi, Davoud; Cheng, Jing; Barrett, Devin G; Guan, Zhibin; Messersmith, Phillip B; Holten-Andersen, Niels

    2015-12-01

    In conventional polymer materials, mechanical performance is traditionally engineered via material structure, using motifs such as polymer molecular weight, polymer branching, or block copolymer design. Here, by means of a model system of 4-arm poly(ethylene glycol) hydrogels crosslinked with multiple, kinetically distinct dynamic metal-ligand coordinate complexes, we show that polymer materials with decoupled spatial structure and mechanical performance can be designed. By tuning the relative concentration of two types of metal-ligand crosslinks, we demonstrate control over the material's mechanical hierarchy of energy-dissipating modes under dynamic mechanical loading, and therefore the ability to engineer a priori the viscoelastic properties of these materials by controlling the types of crosslinks rather than by modifying the polymer itself. This strategy to decouple material mechanics from structure is general and may inform the design of soft materials for use in complex mechanical environments. Three examples that demonstrate this are provided. PMID:26322715

  13. Crystal Structures, Magnetic Properties, and Electrochemical Properties of Coordination Polymers Based on the Tetra(4-pyridyl)-tetrathiafulvalene Ligand.

    PubMed

    Wang, Hai-Ying; Wu, Yue; Leong, Chanel F; D'Alessandro, Deanna M; Zuo, Jing-Lin

    2015-11-16

    Seven new coordination polymers based on the redox-active tetra(4-pyridyl)-tetrathiafulvalene ligand (TTF(py)4) and different transition-metal ions, namely, {[Cu(hfac)2][TTF(py)4]·2(CH2Cl2)}n (1), {[Co(acac)2][TTF(py)4]0.5·(CHCl3)}n (2), {[Mn(hfac)2][TTF(py)4]0.5}n (3), {[Cu2(OAc)4][TTF(py)4]0.5·1.5(CHCl3)·0.5(H2O)·(CH3CN)}n (4), {[Mn(SCN)2][TTF(py)4]·6(CH2Cl2)}n (5), {[Mn(SeCN)Cl][TTF(py)4]}n (6), and {Cu2[TTF(py)4]2·(ClO4)2·2.5(CH2Cl2)·1.5(CH3CN)}n (7), were synthesized and characterized. The tetrapyridyl ligand coordinates to metal ions in a bidentate or tetradentate fashion, forming complexes 1-7 with different structures. Complex 1 exhibits a one-dimensional chain structure. Complexes 2, 3, and 4 possess similar (4,2)-connected binodal two-dimensional networks, while complexes 5 and 6 have similar (4,4)-connected binodal two-dimensional networks with two different rings. Complex 7 shows a 2-fold interpenetrated (4,4)-connected binodal PtS-type three-dimensional framework. Meanwhile, these complexes feature diverse nonclassical hydrogen bonding interactions. In addition, magnetic and solid-state electrochemical properties for typical complexes have been studied. PMID:26512844

  14. Three one-dimensional structural heating programs

    NASA Technical Reports Server (NTRS)

    Wing, L. D.

    1978-01-01

    Two computer programs for calculating profiles in a ten-element structure consisting of up to ten materials are presented, along with a third program for calculating the mean temperature for a payload container placed in an orbiting vehicle cargo bay. The three programs are related by the sharing of a common analytical technique; the energy balance is based upon one-dimensional heat transfer. The first program, NQLDW112, assumes a non-ablating surface. NQLDW117 is very similar but allows the outermost element to ablate. NQLDW040 calculates an average temperature profile through an idealized model of the real payload cannister and contents in the cargo bay of an orbiting vehicle.

  15. One-Dimensional Photonic Crystal Superprisms

    NASA Technical Reports Server (NTRS)

    Ting, David

    2005-01-01

    Theoretical calculations indicate that it should be possible for one-dimensional (1D) photonic crystals (see figure) to exhibit giant dispersions known as the superprism effect. Previously, three-dimensional (3D) photonic crystal superprisms have demonstrated strong wavelength dispersion - about 500 times that of conventional prisms and diffraction gratings. Unlike diffraction gratings, superprisms do not exhibit zero-order transmission or higher-order diffraction, thereby eliminating cross-talk problems. However, the fabrication of these 3D photonic crystals requires complex electron-beam substrate patterning and multilayer thin-film sputtering processes. The proposed 1D superprism is much simpler in structural complexity and, therefore, easier to design and fabricate. Like their 3D counterparts, the 1D superprisms can exhibit giant dispersions over small spectral bands that can be tailored by judicious structure design and tuned by varying incident beam direction. Potential applications include miniature gas-sensing devices.

  16. Electron pairing in one-dimensional quasicrystals

    NASA Astrophysics Data System (ADS)

    Arredondo, Y.; Navarro, O.

    2010-08-01

    Electron pairing in one-dimensional binary Hubbard chains is studied for different values of the band-filling using the density matrix renormalization group method. The systems consist of linear arrays of sites with two types of on-site correlations defined by two potentials: UA being attractive (<0), and UB repulsive (>0). The atomic levels of the system are modulated with periodic and quasiperiodic ordering, in the latter case following the Fibonacci sequence. We analyze the effect of such modulations and calculate the electron pairing phase diagram as a function of the band-filling. It is observed that there is a critical value of the band-filling where the behavior of the periodic and the Fibonacci binary Hubbard chains is reversed.

  17. Cohesive motion in one-dimensional flocking

    E-print Network

    V. Dossetti

    2011-11-17

    A one-dimensional rule-based model for flocking, that combines velocity alignment and long-range centering interactions, is presented and studied. The induced cohesion in the collective motion of the self-propelled agents leads to a unique group behaviour that contrasts with previous studies. Our results show that the largest cluster of particles, in the condensed states, develops a mean velocity slower than the preferred one in the absence of noise. For strong noise, the system also develops a non-vanishing mean velocity, alternating its direction of motion stochastically. This allows us to address the directional switching phenomenon. The effects of different sources of stochasticity on the system are also discussed.

  18. One-dimensional magnetic inorganic-organic hybrid nanomaterials.

    PubMed

    Yuan, Jiayin; Xu, Youyong; Müller, Axel H E

    2011-02-01

    One-dimensional (1D) magnetic inorganic-organic hybrid nanomaterials bear both the intrinsic magnetic properties of the inorganic components and the functionality and responsiveness of their organic part. In this tutorial review, we first emphasize various synthetic strategies for this type of materials: (i) template-directed synthesis employs different preformed templates such as channels in solids, mesostructures self-assembled from block copolymers, cylindrical polymer brushes, 1D biological templates and other existing 1D templates; (ii) electrospinning, which provides a simple and efficient technique that can lead to a potential large-scale production; (iii) 1D conjugation of building blocks which combines the physical attraction of magnetic nanoparticles in a magnetic field with chemical crosslinking and stabilization. The properties, functions and the future trends of these materials are also briefly introduced. It is foreseeable that these hybrid materials will play more and more important roles in the ever-advancing miniaturization of functional devices. PMID:21206943

  19. Nucleotide/Tb(3+) coordination polymer nanoparticles as luminescent sensor and scavenger for nitrite ion.

    PubMed

    Qi, Zewan; You, Qi; Chen, Yang

    2016-01-01

    Newly emerged metal organic coordination polymers have aroused the great interest in designing tailored functional materials. In this study, multiple functional components, luminescent Tb(3+) ion, nucleobase and antenna molecule, were integrated in a single material and prepared into a responsive nanoparticle for nitrite. The terbium coordination polymer nanoparticles made of this kind of material have the dual functions of recognition and transduction and obey a preset sensing mechanism without a post-functionalization of common materials. As the result of the tailored, the terbium coordination polymer nanoparticles are highly sensitive and selective to nitrite by means of Dexter energy transfer between Tb(3+) ion and nitrite, and can be used for the scavenger for nitrite in aqueous solution. The detection limit, dynamic range and removal capacity of U-Tb-OBBA CPNPs for nitrite are 0.3 µM, 0.3-470 µM and 4.44 mg per gram of particles, respectively. Metal organic coordination polymers show an attractive potential in constructing smart sensing materials. PMID:26703267

  20. Novel photochromic infinite coordination polymer particles derived from a diarylethene photoswitch.

    PubMed

    Hu, Xiao Guang; Li, XiaoLiang; Yang, Sung Ik

    2015-07-01

    A novel infinite coordination polymer (DAE-ICP) based on zinc nitrite and a diarylethene photoswitch, with reversible photochromic properties in solution and the solid state upon applying photostimuli, was synthesized and characterized by FT-IR, EDX, FE-SEM and FE-TEM. PMID:26041619

  1. A mixed-valence copper coordination polymer generated by hydrothermal metal/ligand redox reactions

    E-print Network

    Li, Jing

    hydro- thermal conditions and wish to extend this to mixed-valence copper complexes. Copper(I) compounds-valence copper compounds, with hydroxylated bipyridyl ligands,3g have been recently reportedA mixed-valence copper coordination polymer generated by hydrothermal metal/ligand redox reactions

  2. Synthesis, Structure and Spectroscopy Study of a 1D Copper Coordination Polymer Based on a Carboxybenzyl Viologen Ligand and SCN-Anion.

    PubMed

    Qiu, Li-xia; Wan, Fang; Zhu, Bin-bin; Sun, Yan-qiong; You, Yi; Chen, Yi-ping

    2015-05-01

    A zwitterionic viologen derivative ligand, 1,1'-bis(4-carboxybenzyl)-4 4'-bipyridinium dichloride (H2BpybcCl2) as a multifunctional ligand, has been synthesized incorporating a 4,4'-bipyridine core with two carboxylate groups as a. building block, specifically designed for the rational construction of metal-organic frameworks. H2BpybcCl2 ligand is a multifunctional ligand that contains viologen's specific functions and carboxylate coordination groups. The coordination polymers of viologen carboxylate with copper thiocyanate are not reported to date. A novel copper coordination polymer, [Cu(SCN)2 (Bpybc)] (I) was by solution diffusion method and characterized by single-crystal X-ray diffraction, XRD, elemental analyses, IR spectroscopy, UV-Vis DRS, TG analysis and liquid-state luminescent properties. Compound I crystallized in the monoclinic system with C2/c space group. Crystal data for complex I is as follow: a=19. 508(4) A, b=9. 474(2) Å, c =16. 963(3) Å, ?=90°, ?=124. 92(3)°, ?=90°. Two SCN-anions were coordinated to the Cu2+ cation forming a [Cu(SCN)2] unit. Complex I was built up by [Cu(SCN)2] units bridged sequentially by ladder-shaped Bpybc ligands to form one-dimensional zigzag chains running along the [203] direction. The chains were held together by ?-? interaction between the pyridine rings and phenyl rings, thus yielding a 3-D extended supramolecular network. The UV-Visible absorption spectra show the absorption bands of ?-?* transitions of Bpybc ligands and d-->d transition of Cu2+. The liquid-state luminescent property of compound I was investigated at room temperature. Attractively, the complex exhibits strong blue emission peak at 533 nm (?Ex=360 nn) that can be assigned to intraligand transition of Bpybc ligand when it was excited at 360 nm. PMID:26415457

  3. Bio-Inspired Composite Interfaces: Controlling Hydrogel Mechanics via Polymer-Nanoparticle Coordination Bond Dynamics

    NASA Astrophysics Data System (ADS)

    Holten-Andersen, Niels

    2015-03-01

    In soft nanocomposite materials, the effective interaction between polymer molecules and inorganic nanoparticle surfaces plays a critical role in bulk mechanical properties. However, controlling these interfacial interactions remains a challenge. Inspired by the adhesive chemistry in mussel threads, we present a novel approach to control composite mechanics via polymer-particle interfacial dynamics; by incorporating iron oxide nanoparticles (Fe3O4 NPs) into a catechol-modified polymer network the resulting hydrogels are crosslinked via reversible coordination bonds at Fe3O4 NP surfaces thereby providing a dynamic gel network with robust self-healing properties. By studying the thermally activated composite network relaxation processes we have found that the polymer-NP binding energy can be controlled by engineering both the organic and inorganic side of the interface.

  4. Transport in a One-Dimensional Hyperconductor

    E-print Network

    Plamadeala, Eugeniu; Nayak, Chetan

    2015-01-01

    We define a `hyperconductor' to be a material whose electrical and thermal DC conductivities are infinite at zero temperature. The low-temperature behavior of a hyperconductor is controlled by a quantum critical phase of interacting electrons that is stable to all potentially-gap-generating interactions and potentially-localizing disorder. In this paper, we compute the low-temperature DC and AC electrical and thermal conductivities in a one-dimensional hyperconductor, studied previously by the present authors, in the presence of both disorder and umklapp scattering. We identify the conditions under which the transport coefficients are finite, which allows us to exhibit examples of violations of the Wiedemann-Franz law. We show that the temperature dependence of the electrical conductivity is a power law, $\\sigma \\propto 1/T^{1 - 2(2-\\Delta_X)}$ for $\\Delta_X \\geq 2$, down to zero temperature when the Fermi surface is commensurate with the lattice. There is a surface in parameter space along which $\\Delta_X = ...

  5. Transport in a One-Dimensional Hyperconductor

    E-print Network

    Eugeniu Plamadeala; Michael Mulligan; Chetan Nayak

    2015-09-14

    We define a `hyperconductor' to be a material whose electrical and thermal DC conductivities are infinite at zero temperature. The low-temperature behavior of a hyperconductor is controlled by a quantum critical phase of interacting electrons that is stable to all potentially-gap-generating interactions and potentially-localizing disorder. In this paper, we compute the low-temperature DC and AC electrical and thermal conductivities in a one-dimensional hyperconductor, studied previously by the present authors, in the presence of both disorder and umklapp scattering. We identify the conditions under which the transport coefficients are finite, which allows us to exhibit examples of violations of the Wiedemann-Franz law. We show that the temperature dependence of the electrical conductivity is a power law, $\\sigma \\propto 1/T^{1 - 2(2-\\Delta_X)}$ for $\\Delta_X \\geq 2$, down to zero temperature when the Fermi surface is commensurate with the lattice. There is a surface in parameter space along which $\\Delta_X = 2$ and $\\Delta_X \\approx 2$ for small deviations from this surface. In the generic (incommensurate) case with weak disorder, such scaling is seen at high-temperatures, followed by an exponential increase of the conductivity $\\ln \\sigma \\sim 1/T$ at intermediate temperatures and, finally, $\\sigma \\propto 1/T^{2-2(2-{\\Delta_X})}$ at the lowest temperatures. In both cases, the thermal conductivity diverges at low temperatures.

  6. Exciton quasicondensation in one-dimensional systems

    NASA Astrophysics Data System (ADS)

    Werman, Yochai; Berg, Erez

    2015-06-01

    Two Luttinger liquids, with an equal density and opposite sign of charge carriers, may exhibit enhanced excitonic correlations. We term such a system an exciton quasicondensate, with a possible realization being two parallel oppositely doped quantum wires, coupled by repulsive Coulomb interactions. We show that this quasiexciton condensate can be stabilized in an extended range of parameters, in both spinless and spinful systems. We calculate the interwire tunneling current-voltage characteristic, and find that a negative differential conductance is a signature of excitonic correlations. For spinful electrons, the excitonic regime is shown to be distinct from the usual quasi-long-range ordered Wigner crystal phase characterized by power-law density wave correlations. The two phases can be clearly distinguished through their interwire tunneling current-voltage characteristics. In the quasiexciton condensate regime the tunneling conductivity diverges at low temperatures and voltages, whereas in the Wigner crystal it is strongly suppressed. Both the Wigner crystal and the excitonic regime are characterized by a divergent Coulomb drag at low temperature. Finally, metallic carbon nanotubes are considered as a special case of such a one-dimensional setup, and it is shown that exciton condensation is favorable due to the additional valley degree of freedom.

  7. A one dimensional model of population growth

    NASA Astrophysics Data System (ADS)

    Ribeiro, Fabiano L.; Ribeiro, Kayo N.

    2015-09-01

    In this work, a one dimensional population growth model is proposed. The model, based on the cooperative and competitive individual-individual distance-dependent interaction, allows us to get a full analytical solution. With this analytical approach, it was possible to investigate the dynamics of the population according to some parameters, as intrinsic growth rate, strength of the interaction between individuals, and the distance-dependent interaction. As a consequence of the individuals' interaction, a rich phase diagram to which the population has access was observed. The phases observed are: convergence to carrying capacity, exponential growth, divergence at finite time, and extinction. Moreover, it was also observed that some phases are strictly dependent on the initial condition. For instance, in the cooperative regime with negative intrinsic growth rate, the population can diverge or become extinct according to the initial population size. The phases accessible to the population can be seen as a macroscopic behavior which emerges from the interaction among the individuals (the microscopic level).

  8. HOMOLOGY FOR ONE-DIMENSIONAL SOLENOIDS MASSOUD AMINI1

    E-print Network

    Putnam, Ian F.

    HOMOLOGY FOR ONE-DIMENSIONAL SOLENOIDS MASSOUD AMINI1 , IAN F. PUTNAM2 AND SARAH SAEIDI GHOLIKANDI1 and phrases. Smale spaces, one-dimensional generalized solenoids, homology. 1 #12;2 MASSOUD AMINI, IAN F

  9. HOMOLOGY FOR ONE-DIMENSIONAL SOLENOIDS MASSOUD AMINI1

    E-print Network

    Putnam, Ian F.

    HOMOLOGY FOR ONE-DIMENSIONAL SOLENOIDS MASSOUD AMINI1 , IAN F. PUTNAM2 AND SARAH SAEIDI GHOLIKANDI1. Smale spaces, one-dimensional generalized solenoids, homology. 1 #12;2 MASSOUD AMINI, IAN F. PUTNAM

  10. Thermal and Electrical Transport Study of One Dimensional Nanomaterials 

    E-print Network

    Yin, Liang

    2013-07-13

    This dissertation presents experimental and computational study of thermal and electrical transport in one-dimensional nanostructures. Synthesizing materials into one-dimensional nanowire has been proved very effective for suppressing the phonon...

  11. Quantum simulations of one dimensional quantum systems

    E-print Network

    Rolando D. Somma

    2015-03-21

    We present several quantum algorithms for the simulation of quantum systems in one spatial dimension. First, we provide a method to simulate the evolution of the quantum harmonic oscillator (QHO) and compute scattering amplitudes using a discrete QHO. To achieve precision \\epsilon, it suffices to choose the dimension of the Hilbert space of the discrete system, N, proportional to N' and logarithmic in |t|/\\epsilon, where N' is the largest eigenvalue in the spectral decomposition of the initial state, and t is the evolution time. We then present a Trotter-Suzuki product formula to approximate the evolution. The number of terms in the product is subexponential, and the complexity of simulating the evolution on a quantum computer is O(|t| \\exp( \\gamma \\sqrt{\\log(N' |t|/\\epsilon)})), where \\gamma >0 is constant. Our results suggest a superpolynomial speedup. Next, we describe a quantum algorithm to prepare the ground state of the discrete QHO with complexity polynomial in \\log(1/\\epsilon) and \\log (N). Such a quantum algorithm may be of independent interest, as it gives a way to prepare states of Gaussian-like amplitudes. Other eigenstates can be prepared by evolving with a Hamiltonian that is a discrete version of the Jaynes-Cummings model, with complexity polynomial in \\log (N) and 1/\\epsilon. We then study a quantum system with a quartic potential and numerically show that the evolution operator can be approximated using the Trotter-Suzuki formula, where the number of terms scales as N^{q}, for q simulating a large class of one-dimensional quantum systems, and describe a quantum algorithm of complexity almost linear in N|t| and logarithmic in 1/\\epsilon. We discuss further applications of our results, in particular with regards to the fractional Fourier transform.

  12. Novel 3D bismuth-based coordination polymers: Synthesis, structure, and second harmonic generation properties

    SciTech Connect

    Wibowo, Arief C.; Smith, Mark D.; Yeon, Jeongho; Halasyamani, P. Shiv; Loye, Hans-Conrad zur

    2012-11-15

    Two new 3D bismuth containing coordination polymers are reported along with their single crystal structures and SHG properties. Compound 1: Bi{sub 2}O{sub 2}(pydc) (pydc=pyridine-2, 5-dicarboxylate), crystallizes in the monoclinic, polar space group, P2{sub 1} (a=9.6479(9) A, b=4.2349(4) A, c=11.9615(11) A, {beta}=109.587(1) Degree-Sign ), which contains Bi{sub 2}O{sub 2} chains that are connected into a 3D structure via the pydc ligands. Compound 2: Bi{sub 4}Na{sub 4}(1R3S-cam){sub 8}(EtOH){sub 3.1}(H{sub 2}O){sub 3.4} (1R3S cam=1R3S-camphoric acid) crystallizes in the monoclinic, polar space group, P2{sub 1} (a=19.0855(7) A, b=13.7706(5) A, c=19.2429(7) A, {beta}=90.701(1) Degree-Sign ) and is a true 3D coordination polymer. These are two example of SHG compounds prepared using unsymmetric ligands (compound 1) or chiral ligands (compound 2), together with metals that often exhibit stereochemically-active lone pairs, such as Bi{sup 3+}, a synthetic approach that resulted in polar, non-centrosymmetric, 3D metal-organic coordination polymer. - Graphical Abstract: Structures of two new, polar, 3D Bismuth(III)-based coordination polymers: Bi{sub 2}O{sub 2}(pydc) (compound 1), and Bi{sub 4}Na{sub 4}(1R3S-cam){sub 8}(EtOH){sub 3.1}(H{sub 2}O){sub 3.4} (compound 2). Highlights: Black-Right-Pointing-Pointer New, polar, 3D Bismuth(III)-based coordination polymers. Black-Right-Pointing-Pointer First polar bismuth-based coordination polymers synthesized via a 'hybrid' strategy. Black-Right-Pointing-Pointer Combination of stereochemically-active lone pairs and unsymmetrical or chiral ligands. Black-Right-Pointing-Pointer Synthesis of class C-SHG materials based on Kurtz-Perry categories.

  13. Uranium(VI) coordination polymers with pyromellitate ligand: Unique 1D channel structures and diverse fluorescence

    NASA Astrophysics Data System (ADS)

    Zhang, Yingjie; Bhadbhade, Mohan; Karatchevtseva, Inna; Price, Jason R.; Liu, Hao; Zhang, Zhaoming; Kong, Linggen; ?ejka, Ji?í; Lu, Kim; Lumpkin, Gregory R.

    2015-03-01

    Three new coordination polymers of uranium(VI) with pyromellitic acid (H4btca) have been synthesized and structurally characterized. (ED)[(UO2)(btca)]·(DMSO)·3H2O (1) (ED=ethylenediammonium; DMSO=dimethylsulfoxide) has a lamellar structure with intercalation of ED and DMSO. (NH4)2[(UO2)6O2(OH)6(btca)]·~6H2O (2) has a 3D framework built from 7-fold coordinated uranyl trinuclear units and btca ligands with 1D diamond-shaped channels (~8.5 Å×~8.6 Å). [(UO2)2(H2O)(btca)]·4H2O (3) has a 3D network constructed by two types of 7-fold coordinated uranium polyhedron. The unique ?5-coordination mode of btca in 3 enables the formation of 1D olive-shaped large channels (~4.5 Å×~19 Å). Vibrational modes, thermal stabilities and fluorescence properties have been investigated.

  14. Syntheses, structures and photoelectric properties of a series of Cd(II)/Zn(II) coordination polymers and coordination supramolecules

    SciTech Connect

    Jin Jing; Han Xiao; Meng Qin; Li Dan; Chi Yuxian; Niu Shuyun

    2013-01-15

    Five Cd(II)/Zn(II) complexes [Cd(1,2-bdc)(pz){sub 2}(H{sub 2}O)]{sub n} (1), [Cd1Cd2(btec)(H{sub 2}O){sub 6}]{sub n} (2), [Cd(3,4-pdc) (H{sub 2}O)]{sub n} (3), [Zn(2,5-pdc)(H{sub 2}O){sub 4}]{center_dot}2H{sub 2}O (4) and {l_brace} [Zn(2,5-pdc)(H{sub 2}O){sub 2}]{center_dot}H{sub 2}O{r_brace} {sub n} (5) (H{sub 2}bdc=1,2-benzenedicarboxylic acid, pz=pyrazole, H{sub 4}btec=1,2,4,5-benzenetetracarboxylic acid, H{sub 2}pdc=pyridine-dicarboxylic acid) were hydrothermally synthesized and characterized by single-crystal X-ray diffraction, surface photovoltage spectroscopy, XRD, TG analysis, IR and UV-vis spectra and elemental analysis. Structural analyses show that complexes 1-3 are 1D, 2D and 3D Cd(II) coordination polymers, respectively. Complex 4 is a mononuclear Zn(II) complex. Complex 5 is a 3D Zn(II) coordination polymer. The surface photoelectric properties of complexes were investigated by SPS. The results indicate that all complexes exhibit photoelectric responses in the range of 300-600 nm, which reveals that they all possess certain photoelectric conversion properties. By the comparative analyses, it can be found that the species and coordination micro-environment of central metal ion, the species and property of ligands affect the intensity and scope of photoelectric response. - Graphical abstract: Five Cd(II)/Zn(II) complexes have been hydrothermally synthesized and characterized. The photoelectric properties were studied with SPS. The species and coordination micro-environment of central metal ion, the species and property of ligands all affect the photoelectric responses. Highlights: Black-Right-Pointing-Pointer Five Cd/Zn complexes have been synthesized and characterized. Black-Right-Pointing-Pointer The SPS results indicate they possess obvious photoelectric conversion property. Black-Right-Pointing-Pointer The species and coordination environment of central metal ion affect SPS. Black-Right-Pointing-Pointer The species and property of ligands affect SPS. Black-Right-Pointing-Pointer By the energy-band theory and the crystal filed theory, the SPS are analyzed and assigned.

  15. Application of a silver-olefin coordination polymer as a catalytic curing agent for self-healing epoxy polymers

    NASA Astrophysics Data System (ADS)

    Everitt, D. T.; Coope, T. S.; Trask, R. S.; Wass, D. F.; Bond, I. P.

    2015-05-01

    A silver-olefin based coordination polymer was prepared in a simple, one step process to act as an initiator to facilitate the ring-opening polymerization of epoxides. Thermal analysis found the complex to be capable of curing a range of commercially available epoxy resins used in the manufacture of conventional composite materials. Curing of the oligomeric diglycidyl ether bisphenol A resin, Epon 828, in combination with a non-toxic solvent, ethyl phenylacetate, was studied by differential scanning calorimetry. The mechanical characterization of the resultant cured polymers was conducted by single lap shear tests. Tapered double cantilever beam (TDCB) test specimens containing 2.5 pph of silver-olefin initiator, both with and without embedded microcapsules, were analyzed for their healing performance. Healing efficiency values were found to be strongly dependent on the applied healing temperature. A mean recovery of 74% fracture load was found in TDCB samples after being healed at 70 °C for 48 h.

  16. Morphological Transformation Reactions of Photocatalytic Metalloporphyrin-Containing Coordination Polymer Particles from Seed Structures

    PubMed Central

    Sun, Yu; Yoo, Bongyoung

    2015-01-01

    Coordination polymer particles have attracted a great deal of attention due to their characteristic properties and diverse applications in the fields of gas storage, catalysis, optics, sensing, electronics, photochemistry, and biology. Herein, we investigated shape transformation reactions of zinc 5, 10, 15, 20-tetra(4-pyridyl)-21?H, 23?H-porphine (ZnTPyP)-containing coordination polymer particles (ZnTPyP?CPPs) from seed structures by delicately controlling the Gibbs energy of the self-assembly system. We obtained a morphological transformation from 1?D short nanorods to 1?D long nanorods and 3?D nano-octahedral structures, and from 3?D nano-octahedral structures to 1?D nanorod structures. We illustrated a new method to design and synthesize metalloporphyrin-containing CPPs in a controllable manner. Furthermore, photocatalytic properties of ZnTPyP?CPPs were tested, showing good catalytic abilities towards the photodegradation of methylene blue (MB) under visible light illumination. PMID:26478836

  17. The synthesis, crystal structure and magnetic properties of a one-dimensional terbium(III)-octacyanidomolybdate(V) assembly.

    PubMed

    Shen, Hong

    2014-12-01

    A one-dimensional cyanide-bridged coordination polymer, poly[[aquadi-?-cyanido-?(4)C:N-hexacyanido-?(6)C-(dimethylformamide-?O)bis(3,4,7,8-tetramethyl-1,10-phenanthroline-?(2)N,N')terbium(III)molybdate(V)] 4.5-hydrate], [MoTb(CN)8(C16H16N2)2(C3H7NO)(H2O)]·4.5H2O}n, has been prepared and characterized through IR spectroscopy, elemental analysis and single-crystal X-ray diffraction. The compound consists of one-dimensional chains in which cationic [Tb(tmphen)2(DMF)(H2O)](3+) (tmphen is 3,4,7,8-tetramethyl-1,10-phenanthroline) and anionic [Mo(V)(CN)8](3-) units are linked in an alternating fashion through bridging cyanide ligands. Neighbouring chains are connected by three types of hydrogen bonds (O-H···O, O-H···N and C-H···O) and by ?-? interactions to form a three-dimensional supramolecular structure. In addition, magnetic investigations show that ferromagnetic interactions exist in the compound. PMID:25471419

  18. Solvent-induced delamination of a multifunctional two dimensional coordination polymer.

    PubMed

    Gallego, Almudena; Hermosa, Cristina; Castillo, Oscar; Berlanga, Isadora; Gómez-García, Carlos J; Mateo-Martí, Eva; Martínez, José I; Flores, Fernando; Gómez-Navarro, Cristina; Gómez-Herrero, Julio; Delgado, Salome; Zamora, Félix

    2013-04-18

    A coordination polymer is fully exfoliated by solvent-assisted interaction only. The soft-delamination process results from the structure of the starting material, which shows a layered structure with weak layer-to-layer interactions and cavities with the ability to locate several solvents in an unselective way. These results represent a significant step forward towards the production of structurally designed one-molecule thick 2D materials with tailored physico-chemical properties. PMID:23345141

  19. Polymer complexes. LIII. Supramolecular coordination modes and structural of novel sulphadrug complexes

    NASA Astrophysics Data System (ADS)

    Diab, M. A.; El-Sonbati, A. Z.; Mohamed, R. H.

    2010-11-01

    Novel polymer complexes of copper(II), palladium(II), platinum(II) and cadmium(II) containing homopolymer [4-acrylamido benzene sulphonyl guanidine; (HL)] and various anions (SO 42-, CH 3COO -, NO 3-, Br - or Cl -) have been designed and carried out. Their structures were investigated by elemental analyses, spectral (IR, UV-vis, 1H NMR and ESR) and magnetic moments. The modes of interactions between the ligand and the metals were discussed, where oxygen (of O dbnd S dbnd O group) and nitrogen atom [of imino nitrogen (NH/N) of the guanidine group] are involved in chelation. The homopolymer shows two types of coordination behaviour. In mononuclear polymer complexes 4 and 6- 10, it acts as a neutral bidentate ligand chelated through the NH and O atoms, whereas in the polymer complexes 1- 3, 5 and 11, monobasic bidentate ligand is coordinated through the -N and -O atoms. The poly-chelates are of 1:1/1:2 (metal-homopolymer) stoichiometry and exhibit four coordination. On the basis of electronic spectral data and magnetic susceptibility measurement square planar geometry has been proposed. The ESR spectral data provided information about their structure on the basis Hamiltonian parameters and degree of covalency. From the electron paramagnetic resonance and spectral data, the orbital reduction factors were calculated.

  20. Micromolding of a Highly Fluorescent Reticular Coordination Polymer: Solvent-Mediated Reconfigurable Polymerization in a Soft Lithographic Mold

    SciTech Connect

    Y You; H Yang; J Chung; J Kim; Y Jung; S Park

    2011-12-31

    Coordination polymerization of pyridine-based ligands and zinc or silver ions was controlled by soft lithographic micromolding in capillaries. The polymer patterns that are produced are highly fluorescent and supramolecularly structured.

  1. One 1D T4(0)A(0) water tape embedded in a 1D Cu(II) coordination polymer with 1,3-bis(4-pyridyl)propane

    NASA Astrophysics Data System (ADS)

    Xiong, Hong-Bo; Sun, Di; Luo, Geng-Geng; Huang, Rong-Bin; Dai, Jing-Cao

    2011-03-01

    The reaction of Cu(OH) 2 ( in situ synthesized from CuCl 2·2H 2O and NaOH), bpp and H 2ox gave rise to a novel Cu(II) coordination polymer under ultrasonic irradiation at ambient temperature, namely [Cu(bpp)(ox)(H 2O)·5H 2O] n ( 1) (bpp = 1,3-bis(4-pyridyl)propane, H 2ox = oxalic acid). In the complex 1, Cu(II) cations are bridged by bpp ligands to form a one-dimensional (1D) infinite wave-like polymeric chain. The coordinated ox 2- anions and water molecules interact with each other by six different hydrogen-bonding motifs and extend the 1D polymeric chain into a two-dimensional (2D) bilayer pattern. Of further interest, one 1D T4(0)A(0) water tape consisting of alternate cyclic water tetramers resides in the channel structure of 1.

  2. One-dimensional rigid film acoustic metamaterials

    NASA Astrophysics Data System (ADS)

    Ma, Fuyin; Wu, Jiu Hui; Huang, Meng

    2015-11-01

    We have designed a 1D film-type acoustic metamaterial structure consisting of several polymer films directly stacked on each other. It is experimentally revealed that the mass density law can be broken by such structures in the low frequency range. By comparing the sound transmission loss (STL) curves of structures with different numbers of cycles, materials and incident sound directions, several physical properties of the 1D film-type acoustic metamaterial are revealed, which consist of cyclical effects, surface effects and orientation effects. It is suggested that the excellent low frequency sound insulation capacity is influenced by both the cycle number and the stiffness of the film surface. Meanwhile, the surface effect plays a dominant role among these physical properties. Due to the surface acoustic property, for structures with a particular combination form, the STL dominated by the cyclical effects may reach saturation with increasing number of construction periods. Moreover, in some cases, the sound insulation ability is diverse for different sound incidence directions. This kind of 1D film-type periodic structure with these special physical properties provides a new concept for the regulation of sound waves.

  3. A novel 2D coordination polymer based on a copper(II) tetramer with p-sulfonated thiacalix[4]arene

    E-print Network

    Gao, Song

    and copper sulfate hydrate, dark brown crystals of [Cu4(3)(H2O)4(SO4)] Á C5H5NHþ Á H3Oþ Á 8.5H2O (4) wereA novel 2D coordination polymer based on a copper(II) tetramer with p-sulfonated thiacalix[4]arene.V. All rights reserved. Keywords: Crystal structure; 2D Coordination polymer; Copper tetramer; p

  4. Journal of Chemical Crystallography, Vol. 30, No. 3, 2000 A novel two-dimensional 4f-3d coordination polymer

    E-print Network

    Gao, Song

    coordination polymer Ce2Co3(EDTA)3(H2O)11 12H2O Song Gao,(1) * Ou Bai,(1) Bao-Qing Ma,(1) Tao Yi,(1) Chun coordination polymer Ce2Co3(EDTA)3 (H2O)11 12H2O (EDTA ethylenediamine-N,N,N ,N -tetraacetate) has been synthesized using complex Na[Ce(EDTA)] as ligand. The complex crystallines in the space group C2, with lattice

  5. One-dimensional zinc oxide nanomaterials synthesis and photovoltaic applications

    NASA Astrophysics Data System (ADS)

    Weintraub, Benjamin A.

    As humanly engineered materials systems approach the atomic scale, top-down manufacturing approaches breakdown and following nature's example, bottom-up or self-assembly methods have the potential to emerge as the dominant paradigm. Synthesis of one-dimensional nanomaterials takes advantage of such self-assembly manufacturing techniques, but until now most efforts have relied on high temperature vapor phase schemes which are limited in scalability and compatibility with organic materials. The solution-phase approach is an attractive low temperature alternative to overcome these shortcomings. To this end, this thesis is a study of the rationale solution-phase synthesis of ZnO nanowires and applications in photovoltaics. The following thesis goals have been achieved: rationale synthesis of a single ZnO nanowire on a polymer substrate without seeding, design of a wafer-scale technique to control ZnO nanowire array density using layer-by-layer polymers, determination of optimal nanowire field emitter density to maximize the field enhancement factor, design of bridged nanowires across metal electrodes to order to circumvent post-synthesis manipulation steps, electrical characterization of bridged nanowires, rationale solution-phase synthesis of long ZnO nanowires on optical fibers, fabrication of ZnO nanowire dye-sensitized solar cells on optical fibers, electrical and optical characterization of solar cell devices, comparison studies of 2-D versus 3-D nanowire dye-sensitized solar cell devices, and achievement of 6-fold solar cell power conversion efficiency enhancement using a 3-D approach. The thesis results have implications in nanomanufacturing scale-up and next generation photovoltaics.

  6. Ultrathin 2D coordination polymer nanosheets by surfactant-mediated synthesis.

    PubMed

    Junggeburth, Sebastian C; Diehl, Leo; Werner, Stephan; Duppel, Viola; Sigle, Wilfried; Lotsch, Bettina V

    2013-04-24

    Low-dimensional nanostructures offer a host of intriguing properties which are distinct from those of the bulk material, owing to size-confinement effects and amplified surface areas. Here, we report on the scalable, bottom-up synthesis of ultrathin coordination polymer nanosheets via surfactant-mediated synthesis and subsequent exfoliation. Layers of a two-dimensional (2D) zinc coordination polymer are self-assembled in the interlamellar space of a reverse microemulsion mesophase into stacks of nanosheets interleaved with cethyltrimethylammonium bromide (CTAB) at regular intervals, thus giving rise to a lamellar hybrid mesostructure with a lattice period of ~8 nm and an underlying highly crystalline substructure. The basic structural motif is composed of 2D acetato-benzimidazolato-zinc layers of tetrahedrally coordinated zinc joined together by anionic acetate and benzimidazolate ligands. The hierarchical structure was studied by PXRD, TEM, EDX, EELS, AFM, and solid-state NMR spectroscopy, revealing a high level of order on both the atomic and mesoscale, suggesting fairly strong interactions along the organic-inorganic hybrid interface. Exfoliation of the hybrid material in organic solvents such as THF and chloroform yields sheet- and belt-like nanostructures with lateral sizes between 10's and 100's of nanometers and a height of about 10 nm measured by AFM, which precisely maps the basal spacing of the lamellar mesostructure; further exfoliation results in nanobelts with minimum sizes around 4 nm. Finally, the sheetlike nanostructures behave as morphological chameleons, transforming into highly regular multiwalled coordination polymer nanotubes upon treatment with organic solvents. PMID:23484861

  7. Multi-symplectic, Lagrangian, one-dimensional gas dynamics

    NASA Astrophysics Data System (ADS)

    Webb, G. M.

    2015-05-01

    The equations of Lagrangian, ideal, one-dimensional, compressible gas dynamics are written in a multi-symplectic form using the Lagrangian mass coordinate m and time t as independent variables, and in which the Eulerian position of the fluid element x = x(m, t) is one of the dependent variables. This approach differs from the Eulerian, multi-symplectic approach using Clebsch variables. Lagrangian constraints are used to specify equations for xm, xt, and St consistent with the Lagrangian map, where S is the entropy of the gas. We require St = 0 corresponding to advection of the entropy S with the flow. We show that the Lagrangian Hamiltonian equations are related to the de Donder-Weyl multi-momentum formulation. The pullback conservation laws and the symplecticity conservation laws are discussed. The pullback conservation laws correspond to invariance of the action with respect to translations in time (energy conservation) and translations in m in Noether's theorem. The conservation law due to m-translation invariance gives rise to a novel nonlocal conservation law involving the Clebsch variable r used to impose ?S(m, t)/?t = 0. Translation invariance with respect to x in Noether's theorem is associated with momentum conservation. We obtain the Cartan-Poincaré form for the system, and use it to obtain a closed ideal of two-forms representing the equation system.

  8. Multi-Symplectic Lagrangian, One-Dimensional Gas Dynamics

    E-print Network

    G. M. Webb

    2015-02-12

    The equations of Lagrangian, ideal, one-dimensional (1D), compressible gas dynamics are written in a multi-symplectic form using the Lagrangian mass coordinate $m$ and time $t$ as independent variables, and in which the Eulerian position of the fluid element $x=x(m,t)$ is one of the dependent variables. This approach differs from the Eulerian, multi-symplectic approach using Clebsch variables. Lagrangian constraints are used to specify equations for $x_m$, $x_t$ and $S_t$ consistent with the Lagrangian map, where $S$ is the entropy of the gas. We require $S_t=0$ corresponding to advection of the entropy $S$ with the flow. We show that the Lagrangian Hamiltonian equations are related to the de Donder-Weyl multi-momentum formulation. The pullback conservation laws and the symplecticity conservation laws are discussed. The pullback conservation laws correspond to invariance of the action with respect to translations in time (energy conservation) and translations in $m$ in Noether's theorem. The conservation law due to $m$-translation invariance gives rise to a novel nonlocal conservation law involving the Clebsch variable $r$ used to impose $\\partial S(m,t)/\\partial t=0$. Translation invariance with respect to $x$ in Noether's theorem is associated with momentum conservation. We obtain the Cartan-Poincar\\'e form for the system, and use it to obtain a closed ideal of two-forms representing the equation system.

  9. Coordination polymers assembled from semirigid fluorene-based ligand: A couple of enantiomers

    NASA Astrophysics Data System (ADS)

    Li, Liang; Wang, Zihao; Chen, Qiang; Zhou, Xinhui; yang, Tao; Zhao, Qiang; Huang, Wei

    2015-11-01

    A couple of Mg(II)-based coordination polymer enantiomers [MgL(DMF)(H2O)3]n (R-MgL and S-MgL), and a Zn(II)-based coordination polymer [ZnL(DMF)]n (ZnL) have been synthesized by the solvothermal reactions between the achiral ligand 4,4?-(9,9-dimethyl-9H-fluorene-2,7-diyl)dibenzoic acid (H2L) and the corresponding metal salts. The MgL was obtained as the racemic conglomerate from the one pot reaction. The single crystal X-ray structural analyses reveal that MgL crystallize in the chiral space group P21 and possesses the right- or left-handed homochiral 1D Mg-O-C helical chain. The ZnL crystallize in the non-centrosymmetrical space group Aba2 and possesses the 2D network comprised of 1D Zn-O-C meso-helical chains and ligands. The MgL and ZnL complexes exhibit strong coordination-perturbed ligand-centered blue emissions when excited at 320 nm. Their second-order nonlinear optical effects and thermal properties have also been studied.

  10. Hierarchical effect behind the supramolecular chirality of silver(I)-cysteine coordination polymers.

    PubMed

    Randazzo, Rosalba; Di Mauro, Alessandro; D'Urso, Alessandro; Messina, Gabriele C; Compagnini, Giuseppe; Villari, Valentina; Micali, Norberto; Purrello, Roberto; Fragalà, Maria Elena

    2015-04-01

    Cysteine is a sulfur-containing amino acid that easily coordinates to soft metal ions and grafts to noble metal surfaces. Recently, chiroptical activity of Ag(+)/cysteine coordination polymers has been widely studied, while, on the other hand, the appearance of a plasmon-enhanced circular dichroic signal (PECD) at the plasmonic spectral region (? > 400 nm) has been observed for AgNPs capped with chiral sulfur-containing amino acids. These two events are both potentially exploited for sensing applications. However, the presence of Ag(+) ions in AgNP colloidal solution deals with the competition of cysteine grafting at the metal NP surface and/or metal ion coordination. Herein we demonstrate that the chiroptical activity observed by adding cysteine to AgNP colloids prepared by pulsed laser ablation in liquids (PLAL) is mainly related to the formation of CD-active Ag(+)/cysteine supramolecular polymers. The strict correlation between supramolecular chirality and hierarchical effects, driven by different chemical environments experienced by cysteine when different titration modalities are used, is pivotal to validate cysteine as a fast and reliable probe to characterize the surface oxidation of AgNPs prepared by pulsed laser ablation in liquids by varying the laser wavelengths. PMID:25781213

  11. One-dimensional boron nanostructures: Prediction, synthesis, characterizations, and applications

    E-print Network

    Gao, Hongjun

    One-dimensional boron nanostructures: Prediction, synthesis, characterizations, and applications January 2010, Accepted 24th March 2010 DOI: 10.1039/c0nr00051e One-dimensional (1D) boron nanostructures nanomaterials. In this article, we review the current progress that has been made on 1D boron nanostructures

  12. Exponential decay in one-dimensional porous-thermo-elasticity

    E-print Network

    Politècnica de Catalunya, Universitat

    Exponential decay in one-dimensional porous-thermo-elasticity Pablo S. Casas Dept. Matem" (BFM2003- 00309) of the Spanish Ministry of Science and Technology. Keywords: porous-thermo-elasticity, exponential decay. 0 #12;Decay in one-dimensional porous-thermo-elasticity Abstract This paper concerns

  13. Universality of anomalous one-dimensional heat conductivity Stefano Lepri*

    E-print Network

    Politi, Antonio

    Universality of anomalous one-dimensional heat conductivity Stefano Lepri* Istituto Nazionale di of heat conductivity for d 2. After the publication of the first convincing numerical evidence behavior is addressed with reference to the problem of heat transport in one-dimensional crystals, modeled

  14. Selective Adsorption of CO2 from Light Gas Mixtures Using a Structurally Dynamic Porous Coordination Polymer**

    SciTech Connect

    Kristi L. Kauffman, Jeffrey T. Culp, Andrew J. Allen, Laura Espinal, Winnie Wong-Ng, Thomas D. Brown, Angela Goodman, Mark P. Bernardo, Russel J. Pancoast, Danielle Chirdon, Christopher Matranga*

    2010-01-01

    The selective adsorption of CO{sub 2} from mixtures with N{sub 2}, CH{sub 4}, and N{sub 2}O in a dynamic porous coordination polymer (see monomer structure) was evaluated by ATR-FTIR spectroscopy, GC, and SANS. All three techniques indicate highly selective adsorption of CO{sub 2} from CO{sub 2}/CH{sub 4} and CO{sub 2}/N{sub 2} mixtures at 30 C, with no selectivity observed for the CO{sub 2}/N{sub 2}O system.

  15. Beyond Single-Wavelength SHG Measurements: Spectrally-Resolved SHG Studies of Tetraphosphonate Ester Coordination Polymers.

    PubMed

    Zar?ba, Jan K; Bia?ek, Micha? J; Janczak, Jan; Nyk, Marcin; Zo?, Jerzy; Samo?, Marek

    2015-11-16

    Powder second-harmonic generation (SHG) efficiencies are usually measured at single wavelengths. In the present work, we provide a proof of concept of spectrally resolved powder SHG measured for a newly obtained series of three non-centrosymmetric coordination polymers (CPs). CPs are constructed from tetrahedral linker-tetraphenylmethane-based tetraphosphonate octaethyl ester and cobalt(II) ions of mixed, octahedral (Oh), and tetrahedral (Td), geometries and different sets of donors (CoO6 vs CoX3O). Isostructurality of the obtained materials allowed for the determination of anion-dependent tunability of SHG optical spectra and their relationship with solid-state absorption spectra. PMID:26491884

  16. Lattice architecture effect on the cooperativity of spin transition coordination polymers

    SciTech Connect

    Chiruta, Daniel; Jureschi, Catalin-Maricel; Rotaru, Aurelian E-mail: rotaru@eed.usv.ro; Linares, Jorge E-mail: rotaru@eed.usv.ro; Garcia, Yann

    2014-02-07

    We have investigated in the framework of the Ising-like model, by means of Monte Carlo Metropolis method with open boundary condition, the architecture effect on the cooperativity of spin transition coordination polymers. We have analyzed the influence of several physical parameters (size, pressure, and edge effects) on different lattice architectures which were in good agreement with reported experimental data. We show that the cooperativity of a spin crossover system, characterized by the same number of molecules and the same short- and long-range interaction parameters, is progressively enhanced when going from a 1D chain to a 1D ladder type lattice and to a 2D square lattice.

  17. Hysteretic Spin Crossover in Two-Dimensional (2D) Hofmann-Type Coordination Polymers.

    PubMed

    Liu, Wei; Wang, Lu; Su, Yu-Jun; Chen, Yan-Cong; Tucek, Jiri; Zboril, Radek; Ni, Zhao-Ping; Tong, Ming-Liang

    2015-09-01

    Three new two-dimensional (2D) Hofmann-type coordination polymers with general formula [Fe(3-NH2py)2M(CN)4] (3-NH2py = 3-aminopyridine, M = Ni (1), Pd (2), Pt (3)) have been synthesized. Magnetic susceptibility measurements show that they exhibited cooperative spin crossover (SCO) with remarkable hysteretic behaviors. Their hysteresis widths are 25, 37, and 30 K for 1-3, respectively. The single-crystal structure of 1 suggest that the pseudo-octahedral Fe sites are equatorially bridged by [M(CN)4](2-) to form 2D grids and axially coordinated by 3-NH2py ligands. The intermolecular interactions between layers (the offset face-to-face ?···? interactions, hydrogen bonds, and weak N(amino)···Ni(II) contacts) together with the covalent bonds bridged by [M(CN)4](2-) units are responsible to the significant cooperativity. PMID:26258593

  18. Magnetic and luminescent properties of lanthanide coordination polymers with asymmetric biphenyl-3,2',5'-tricarboxylate.

    PubMed

    Zhao, Jie; Zhu, Guan-Hong; Xie, Li-Qiong; Wu, Ye-Si; Wu, Hai-Lun; Zhou, Ai-Ju; Wu, Zun-Yuan; Wang, Jing; Chen, Yan-Cong; Tong, Ming-Liang

    2015-08-28

    Eight isostructural lanthanide coordination polymers [Ln(bptc)(phen)(H2O)]n (Ln = Dy for , Eu for , Tb for , Gd for , Sm for , Nd for , Yb for , Pr for ) were successfully prepared based on bridging asymmetric polycarboxylate ligand biphenyl-3,2',5'-tricarboxylic acid (H3bptc) and chelating 1,10-phenanthroline (phen) coligand. Single crystal X-ray analysis reveals that complexes have a (3,6)-connected CdI2-type coordination network consisting of paddle-wheel dimers [Ln2(CO2)4]. The magnetic and fluorescent properties of have been investigated. Significantly, the Dy(iii) complex behaves with slow relaxation of the magnetization, where the frequency-dependent out-of-phase signals are noticed. PMID:26202782

  19. 1D coordination polymers with polychalcogenides as linkers between metal atoms

    SciTech Connect

    Kysliak, Oleksandr; Beck, Johannes

    2013-07-15

    The reactions of zinc metal with elemental selenium and selenium/sulfur mixtures in liquid ammonia or methylamine under solvothermal conditions in closed glass ampoules at 50 °C lead within some days specifically to [Zn(NH{sub 3}){sub 2}Se{sub 4}]{sub n} (1), [Zn(MeNH{sub 2}){sub 2}Se{sub 4}]{sub n} (2), [Zn(NH{sub 3}){sub 2}Se{sub 2.23}S{sub 1.77}]{sub n} (3). From MnCl{sub 2}, Rb{sub 2}Se and excess Se in n-butylamine [Mn({sup n}BuNH{sub 2}){sub 4}Se{sub 6}]{sub n} (4) is obtained after prolonged reaction time at ambient temperature. The compounds are sensitive towards air and loss of NH{sub 3} or the amine ligands. The crystal structures were determined by single crystal diffraction at low temperatures. As a common structural feature, all compounds represent 1D coordination polymers with polychalcogenide chains as linkers between the metal atoms and consist of infinite [M–Ch{sub m}–]{sub n} chains (M=Zn, Mn; Ch{sub m}=Se{sub 4}, (S/Se){sub 4}, Se{sub 6}). The Zn central atoms in 1–3 have tetrahedral coordination with two amine ligands, the Mn atoms in 4 have octahedral coordination with four amine ligands and cis position of the two Se atoms. Raman spectra of 1–3 show the stretching mode vibrations of the Ch{sub 4} groups. The observation of S–S, S–Se, and Se–Se vibration bands in the spectrum of 3 indicates the presence of mixed S/Se polyanions. An optical band gap of 1.86(5) eV was determined for 2 by diffuse reflectance spectroscopy. - Graphical abstract: The reaction of Zn and Se in liquid methylamine yields dark red [Zn(NH{sub 2}CH{sub 3})Se{sub 4}], a 1D coordination polymer consisting of helical Zn–Se{sub 4}–Zn– chains. - Highlights: • A series of 1D coordination polymers consisting of metal amine complexes concatenated by polychalcogenide ions is presented. • Syntheses were performed as solvothermal reactions in liquid ammonia, liquid methylamine and n-butylamine. • Crystal structures are dominated by helices [M–Ch{sub m}]{sub n}. • Raman spectra show the presence of mixed S/Se polyanions.

  20. Aromatic carboxylate effect on dimensionality of three bis(benzimidazole)-based cobalt(II) coordination polymers: Syntheses, structures and properties

    SciTech Connect

    Zhang, Ju-Wen; Gong, Chun-Hua; Hou, Li-Li; Tian, Ai-Xiang; Wang, Xiu-Li

    2013-09-15

    Three new metal-organic coordination polymers [Co(4-bbc){sub 2}(bbbm)] (1), [Co(3,5-pdc)(bbbm)]·2H{sub 2}O (2) and [Co(1,4-ndc)(bbbm)] (3) (4-Hbbc=4-bromobenzoic acid, 3,5-H{sub 2}pdc=3,5-pyridinedicarboxylic acid, 1,4-H{sub 2}ndc=1,4-naphthalenedicarboxylic acid and bbbm=1,1-(1,4-butanediyl)bis-1H-benzimidazole) were hydrothermally synthesized and structurally characterized. Polymer 1 is a 1D chain formed by the bbbm ligands and Co{sup II} ions. Polymer 2 exhibits a 2D network with a (3·4·5)(3{sup 2}·4·5·6{sup 2}·7{sup 4}) topology. Polymer 3 possesses a 3D three-fold interpenetrating framework. The versatile structures of title polymers indicate that the aromatic carboxylates have an important influence on the dimensionality of 1–3. Moreover, the thermal stability, electrochemical and luminescent properties of 1–3 were investigated. - graphical abstract: Three bis(benzimidazole)-based cobalt(II) coordination polymers tuned by aromatic carboxylates were hydrothermally synthesized and structurally characterized. The aromatic carboxylates play a key role in the dimensionality of three polymers. The electrochemical and luminescent properties of three polymers were investigated. Display Omitted - Highlights: • Three bis(benzimidazole)-based cobalt(II) coordination polymers tuned by aromatic carboxylates were obtained. • The aromatic carboxylates have an important influence on the dimensionality of three polymers. • The electrochemical and luminescent properties of three polymers were investigated.

  1. Hardening transition in a one-dimensional model for ferrogels

    E-print Network

    M. A. Annunziata; A. M. Menzel; H. Löwen

    2013-06-03

    We introduce and investigate a coarse-grained model for quasi one-dimensional ferrogels. In our description the magnetic particles are represented by hard spheres with a magnetic dipole moment in their centers. Harmonic springs connecting these spheres mimic the presence of a cross-linked polymer matrix. A special emphasis is put on the coupling of the dipolar orientations to the elastic deformations of the matrix, where a memory effect of the orientations is included. Although the particles are displaced along one spatial direction only, the system already shows rich behavior: as a function of the magnetic dipole moment, we find a phase transition between "soft-elastic" states with finite interparticle separation and finite compressive elastic modulus on the one hand, and "hardened" states with touching particles and therefore diverging compressive elastic modulus on the other hand. Corresponding phase diagrams are derived neglecting thermal fluctuations of the magnetic particles. In addition, we consider a situation in which a spatially homogeneous magnetization is initially imprinted into the material. Depending on the strength of the magneto-mechanical coupling between the dipole orientations and the elastic deformations, the system then relaxes to a uniaxially ferromagnetic, an antiferromagnetic, or a spiral state of magnetization to minimize its energy. One purpose of our work is to provide a largely analytically solvable approach that can provide a benchmark to test future descriptions of higher complexity. From an applied point of view, our results could be exploited, for example, for the construction of novel damping devices of tunable shock absorbance.

  2. Spectroscopic properties of a series of Co(II) coordination polymers and the influence of Co(II) coordination environment on photoelectric property.

    PubMed

    Jin, Jing; Gong, Yuanyuan; Li, Lei; Han, Xiao; Meng, Qin; Liu, Yonghua; Niu, Shuyun

    2015-02-25

    Four Co(II) coordination polymers, [Co(suc)]n 1, [Co(pdc)]n 2, {[Co7(suc)4(OH)6(H2O)3]·8H2O}n 3, {[Co(bdc)(phen)(H2O)]·H2O}n 4 (H2suc=succinic acid, H2pdc=pyridine-3,4-dicarboxylic acid, H2bdc=1,2-benzenedicarboxylic acid, phen=1,10-phenanthroline) were hydrothermally synthesized and characterized by X-ray single-crystal diffraction, surface photovoltage spectroscopy (SPS), electrical conductivity, thermogravimetric analysis (TG), ultraviolet visible and near-infrared absorption spectrum (UV-Vis-NIR), infrared spectrum (IR), and elemental analysis. The structural analyses indicate that the coordination numbers of the Co(II) ions are 4, 5, 6 and 6 for the polymers 1-4, respectively. And polymers 1 and 2 exhibit 3D structure formed by suc(2-) and pdc(2-) anions bridging Co(II) ions, respectively. Polymer 3 exhibits a 2D structure with suc(2-) anions bridging seven-nuclear [Co7(OH)6(H2O)3](3-) unit and polymer 4 is a 1D structure bridged by bdc(2-) anions. The surface photoelectric properties of the cobalt polymers were mainly studied by SPS. The results of SPS reveal that all polymers possess certain photoelectric conversion property in the range of 300-800 nm. The influences of the structure, coordination micro-environment of central metal ion and structural dimensionality on response bands of SPS were discussed. PMID:25280332

  3. Variations of structures and solid-state conductivity of isomeric silver(I) coordination polymers having linear and V-shaped thiophene-centered ditriazole ligands

    SciTech Connect

    Hu, Bin; Geng, Jiao; Zhang, Lie; Huang, Wei

    2014-07-01

    A pair of new linear and V-shaped acceptor–donor–acceptor (A?D?A) thiophene-centered ditriazole structural isomers, i.e., 2,5-di(1H-1,2,4-triazol-1-yl)thiophene (L{sup 1}) and 3,4-di(1H-1,2,4-triazol-1-yl)thiophene (L{sup 2}), has been synthesized and characterized. They are used as ?{sub 2}-bridging ligands to prepare a pair of silver(I) coordination polymers formulated as [Ag(L{sup 1})(NO{sub 3})]{sub n} (1) and [Ag(L{sup 2})(NO{sub 3})]{sub n} (2), which are also structural isomers at the supramolecular level. X-ray single-crystal diffraction analyses for 1 and 2 reveal that they exhibit the same one-dimensional (1D) coordination polymers but different structural architectures because of the distinguishable shape and configuration of isomeric ligands (L{sup 1} and L{sup 2}) and the alterations of the coordination numbers. More interestingly, compared with the free ligands, 1D silver(I) polymeric isomers 1 and 2 show significant enhancement of solid-state conductivity to different extents (1.42×10{sup 4} and 2.17×10{sup 3} times), where 6.96 times' enhancement of solid-state conductivity from 1 to 2 has been observed. The formation of Ag–N coordinative bonds and the configurational discrepancy of L{sup 1} and L{sup 2} are believed to play important roles in facilitating the electron transport between molecules, which can also be supported by Density Function Theory calculations of their band gaps. - Graphical abstract: A pair of linear and V-shaped isomeric thiophene-centered ditriazole ligands (L{sup 1}) and L{sup 2} are used to prepare a pair of silver(I) polymeric isomers (1 and 2), where significant enhancement of solid-state conductivity to different extents are observed originating from the distinguishable shape and configuration of isomeric ligands. - Highlights: • A pair of linear and V-shaped thiophene-centered ditriazole structural isomers is prepared. • They are used as µ{sub 2}-bridging ligands to prepare a pair of silver(I) polymeric isomers. • Significant enhancement of solid-state conductivity is observed for each polymeric isomer.

  4. Scandium(III) coordination polymers containing capsules based on two p-sulfonatocalix[4]arenes.

    PubMed

    Webb, H R; Hardie, M J; Raston, C L

    2001-08-17

    Reactions of sodium p-sulfonatocalix[4]arene and scandium(III) tristriflate in the presence, and absence, of [18]crown-6 give the crystalline complexes [Sc2(mu-OH)2(H2O)10][Na4(H2O)8-[calix[4]arene(SO3)4]2).13 H2O and [[Sc2(mu-OH)2(H2O)8][Sc(H2O)4]2[calix[4]-arene(SO3)4-H+]2([18]crown-6).16H2O. Both complexes involve novel coordination polymers with calixarene units linked through sodium or scandium centers and also feature capsule assemblies through to the head-to-head association of calixarenes. A linear array of capsules associated with an infinite chain of aquo-bridged sodium ions, and an aquated hydroxy-bridged scandium(III) dimer, [Sc2(mu-OH)2(H2O)10]4+, are found in the absence of the crown ether. In the presence of [18]crown-6 both hydrated scandium monomers and dimers bridge between calixarenes in a two-dimensional coordination network. The crown ethers reside in cavities created by two calixarenes from adjacent polymeric sheets via a variety of supramolecular interactions(hydrogen-bonding, shape complementarity), and effectively add a third dimension to the network. The extended structure of both of these polymers is highly porous, and resembles a bilayer. PMID:11560333

  5. Syntheses, crystal structures, and properties of new metal--5-bromonicotinate coordination polymers

    NASA Astrophysics Data System (ADS)

    Li, Wenjie; Li, Guoting; Lv, Lulu; Zhao, Hong; Wu, Benlai

    2015-05-01

    Four metal-5-bromonicotinate (Brnic) coordination polymers [Fe(Brnic)2(H2O)2]n (1), [Ni(Brnic)2]n (2), [Ni(Brnic)(bpy)(H2O)2]n·n(Brnic)·4.5nH2O (3), and [Co2(Brnic)3(bpy)2(OH)]n·nH2O (4) have been synthesized and structurally characterized (bpy=4,4?-bipyridine). Complex 1 has corrugated (4,4) sheets formed by ?-Brnic ligands and planar nodes Fe(II). As for 2-4, they all built up from Brnic-bridged dinuclear subunits, but have very different structure features. Complex 2 is a twin-like polymer with (4,4) layers formed by twin paddle-wheel [Ni2(Brnic)4] subunits. Through the bridge coordination of bpy ligands with dinuclear rings [Ni2(Brnic)2] and trigons [Co2(Brnic)3(OH)], 63-topological cationic layers with nanosized grids of 3 and chiral ladder-type double chains of 4 formed, respectively. Notably, halogen-related interactions play an important role in the formation of 3D metallosupermolecules 1-4. The thermostabilities of all compounds have been discussed in detail. Moreover, the magnetic investigations of 2 and 4 indicate that there exist antiferromagnetic interactions in the paddle-wheel [Ni2(Brnic)4] and trigon [Co2(Brnic)3(OH)] cores, respectively.

  6. Utilization of mixed ligands to construct two new coordination polymers: Syntheses, structures and properties

    NASA Astrophysics Data System (ADS)

    Wang, Yansong; Zhou, Zhimin

    2015-08-01

    The use of triazine and aromatic carboxylic acid as mixed chelating ligands in preparing two coordination polymers is described. Two new transition-metal coordination polymers, namely, [Co2(bpdc)4(phdat)2] (1) and [Zn(bpdc)]n (2) (H2bpdc=2,4-biphenyldicarboxylic acid, phdat=2,4-diamine-6-phenyl-1,3,5-triazine), have been hydrothermally synthesized and structurally characterized by IR, elemental analyses, X-ray single-crystal diffraction and TGA. Compound 1 is a 0D structure and extends to a 3D network by two different N-H···O and N-H···N hydrogen bonds. Compound 2 exhibits a 2D network with 44.62 topological net, which contains two kinds of single helical chains. The interactions within each Co(II)-Co(II) pair of compound 1 are antiferromagnetic (g=2.19, J=-22 K, zj?=-0.00351 K). Furthermore, the photoluminescence property of 2 was also investigated in the solid state at room temperature.

  7. Two unusual 12-connected metal–organic coordination polymers with fcu net

    SciTech Connect

    Guo, Sheng-Qi; Tian, Dan; Luo, Yu-Hui; Chen, Xin; Zhang, Hong

    2013-09-15

    Two new three-dimensional 12-connected metal–organic coordination polymers, [Zn{sub 2}(bptc)(H{sub 2}O)]·C{sub 2}H{sub 5}OH·H{sub 2}O (1) and [Cd{sub 4}(bptc){sub 2}(bbi)(H{sub 2}O)]·H{sub 2}O (2) (H4bptc=biphenyl-2,5,2?,5?-tetracarboxylic acid, bbi=1,1?-(1,4-butanediyl)bis(imidazole)), have been solvothermally synthesized and structurally characterized by single crystal X-ray diffraction analyses. All compounds are also characterized by elemental analyses, IR spectra, thermogravimetric (TG) analyses and X-ray powder diffraction (XRD). Topological analysis indicates that both 1 and 2 are 12-connected frameworks with fcu topology, which are based on cuboid cage and rob-like (Cd3) subunit as 12-connected nodes, respectively. Furthermore, the luminescence properties of the two compounds were discussed in detail. - Graphical abstract: Two new compounds with unusual 12-connected fcu topology display intriguing structural feature, as well as luminescence property. Display Omitted - Highlights: • Two new 3D metal–organic coordination polymers based on biphenyl-2,5,2?,5?-tetracarboxylic acid ligand have been synthesized. • Two compounds exhibit rare 12-connected fcu topology. • Photoluminescent property at room temperature has been investigated.

  8. Properties of a One-Dimensional Dirac Liquid

    NASA Astrophysics Data System (ADS)

    Gochan, Matthew; Stokes, James; Bedell, Kevin

    2015-03-01

    Recent experimental results, as well as technological implications, have lead to a resurgence in the analysis of one-dimensional systems. Of particular interest are the technological advances possible in one-dimensional systems; specifically carbon nano-tubes and nano-wires. Here we investigate the properties of a one-dimensional Dirac liquid. We show a distinct change in the behavior of the exponents of quantities such as the correlation functions, density of states, and momentum distribution function. We find that these exponents, as well as relevant thermodynamic and transport properties are independent of density. Additionally, we discuss the consequences the Virial Theorem has on such systems.

  9. Localized cell stimulation by nitric oxide using a photoactive porous coordination polymer platform

    PubMed Central

    Diring, Stéphane; Wang, Dan Ohtan; Kim, Chiwon; Kondo, Mio; Chen, Yong; Kitagawa, Susumu; Kamei, Ken-ichiro; Furukawa, Shuhei

    2013-01-01

    Functional cellular substrates for localized cell stimulation by small molecules provide an opportunity to control and monitor cell signalling networks chemically in time and space. However, despite improvements in the controlled delivery of bioactive compounds, the precise localization of gaseous biomolecules at the single-cell level remains challenging. Here we target nitric oxide, a crucial signalling molecule with site-specific and concentration-dependent activities, and we report a synthetic strategy for developing spatiotemporally controllable nitric oxide-releasing platforms based on photoactive porous coordination polymers. By organizing molecules with poor reactivity into polymer structures, we observe increased photoreactivity and adjustable release using light irradiation. We embed photoactive polymer crystals in a biocompatible matrix and achieve precisely controlled nitric oxide delivery at the cellular level via localized two-photon laser activation. The biological relevance of the exogenous nitric oxide produced by this strategy is evidenced by an intracellular change in calcium concentration, mediated by nitric oxide-responsive plasma membrane channel proteins. PMID:24158008

  10. Preparation of PbS and PbO nanopowders from new Pb(II)(saccharine) coordination polymers

    NASA Astrophysics Data System (ADS)

    Aslani, Alireza; Musevi, Seyid Javad; ?ahin, Ertan; Yilmaz, Veysel T.

    2014-11-01

    Nanopowders and single crystal of new Pb(II) three-dimensional coordination polymer, [Pb(H2O)(?-OAc)(?-sac)]n "PASAC" were synthesized by a sonochemical and branched tube methods (Y?lmaz et al., Z. Anorg. Allg. Chem. 629 (2003) 172). The new nano-structures of Pb(II) coordination polymer were characterized by X-ray crystallography analysis, scanning electron microscopy (SEM), X-ray powder diffraction (XRD), surface analysis (BET), and IR spectroscopy. The crystal structure of these compounds consists of three-dimensional polymeric units. The thermal stability of compounds was studied by thermal gravimetric analysis (TGA) and differential thermal analyses (DTA). PbS and PbO nano-structures were obtained by calcinations of the nano-structures of this coordination polymer at 600 °C.

  11. Exact solution of the one-dimensional Hubbard model with arbitrary boundary magnetic fields

    NASA Astrophysics Data System (ADS)

    Li, Yuan-Yuan; Cao, Junpeng; Yang, Wen-Li; Shi, Kangjie; Wang, Yupeng

    2014-02-01

    The one-dimensional Hubbard model with arbitrary boundary magnetic fields is solved exactly via the Bethe ansatz methods. With the coordinate Bethe ansatz in the charge sector, the second eigenvalue problem associated with the spin sector is constructed. It is shown that the second eigenvalue problem can be transformed into that of the inhomogeneous XXX spin chain with arbitrary boundary fields which can be solved via the off-diagonal Bethe ansatz method.

  12. In situ Oxidation of phenol and o-aminophenol in the channels of 3d-supramolecular coordination polymers

    NASA Astrophysics Data System (ADS)

    Etaiw, Safaa El-Din H.; Werida, Amal H.

    2010-09-01

    The host attractive properties of supramolecular coordination polymers of the type _infty^3 [(R3Sn)3FeIII(CN)6], where R = methyl (I), n-butyl (II), and phenyl (III), afford the ability to be used as effective oxidizing reagents for phenol and o-aminophenol forming new host-guest supramolecular coordination polymers. Phenol was oxidized to 1,4-benzoquinone while o-aminophenol was oxidized to poly-o-aminophenol by the polymers I and II and to 2-aminophenoxazin-3-one by the polymer III. The oxidation products were investigated by methods of spectroscopy and high-performance liquid chromatography. The redox reactions were characterized by first-order kinetics. Moreover, mechanisms of the oxidation processes of phenol and o-aminophenol have been proposed.

  13. High Speed Water Sterilization Using One-Dimensional Nanostructures

    E-print Network

    Cui, Yi

    High Speed Water Sterilization Using One-Dimensional Nanostructures David T. Schoen, Alia P. Schoen for the high speed electrical sterilization of water using silver nanowires, carbon nanotubes, and cotton

  14. Interacting One-Dimensional Fermionic Symmetry-Protected Topological Phases

    E-print Network

    Tang, Evelyn May Yin

    In free fermion systems with given symmetry and dimension, the possible topological phases are labeled by elements of only three types of Abelian groups, 0, Z[subscript 2], or Z. For example, noninteracting one-dimensional ...

  15. Uniqueness of one-dimensional Néel wall profiles

    E-print Network

    Cyrill B. Muratov; Xiaodong Yan

    2015-11-08

    We study the domain wall structure in thin uniaxial ferromagnetic films in the presence of an in-plane applied external field in the direction normal to the easy axis. Using the reduced one-dimensional thin film micromagnetic model, we analyze the critical points of the obtained non-local variational problem. We prove that the minimizer of the one-dimensional energy functional in the form of the N\\'eel wall is the unique (up to translations) critical point of the energy among all monotone profiles with the same limiting behavior at infinity. Thus, we establish uniqueness of the one-dimensional monotone N\\'eel wall profile in the considered setting. We also obtain some uniform estimates for general one-dimensional domain wall profiles.

  16. Static electric field in one-dimensional insulators without boundaries

    E-print Network

    Chen, Kuang-Ting

    In this brief report, we show that in a one-dimensional insulating system with periodic boundary conditions, the coefficient of the ? term in the effective theory is not only determined by the topological index ?i?[superscript ...

  17. Computation of the one-dimensional unwrapped phase

    E-print Network

    Karam, Zahi Nadim

    2006-01-01

    In this thesis, the computation of the unwrapped phase of the discrete-time Fourier transform (DTFT) of a one-dimensional finite-length signal is explored. The phase of the DTFT is not unique, and may contain integer ...

  18. A new quantum approach of one-dimensional photonic crystals

    NASA Astrophysics Data System (ADS)

    Wu, Xiang-Yao; Ma, Ji; Li, Hai-Bo; Liu, Xiao-Jing; Li, Hong; Ba, Nuo; Chen, Wan-Jin; Wu, Yi-Heng; Zhang, Si-Qi

    2016-01-01

    In this paper, we have studied the quantum transmission characteristics of one-dimensional photonic crystal with and without defect layer by the quantum theory approach, and compared the calculation results of classical with quantum theory. We have found some new quantum effects in the one-dimensional photonic crystal. When the incident angle $\\theta=0$, there is no quantum effect. When the incident angle $\\theta\

  19. Syntheses, structures, and properties of Co(II)/Zn(II) mixed-ligand coordination polymers based on 4-[(3,5-dinitrobenzoyl)amino]benzoic acid and 1,4-bis(1-imidazolyl) benzene

    NASA Astrophysics Data System (ADS)

    Yin, Fei; Chen, Jing; Liang, Yongfeng; Zou, Yang; Yinzhi, Jiang; Xie, Jingli

    2015-05-01

    Two coordination polymers [Co(dnbab)2(bimb)](H2O)4 (1) and [Zn(dnbab)2(bimb)](H2O)5 (2) (Hdnbab=4-[(3,5-dinitrobenzoyl)amino]benzoic acid, bimb=1,4-bis(1-imidazolyl) benzene) have been solvothermally synthesized. Their structures have been determined by single-crystal X-ray diffraction analyses and further characterized by powder X-ray diffraction (PXRD) and thermogravimetric (TG) analyses. Complexes 1 and 2 are isostructures and each displays an one-dimensional (1D) zigzag chain, which further forms a 3D supramolecular architecture with 1-D channels via inter-chain ?-? interactions and hydrogen bonds. Moreover, the magnetic properties of 1 and fluorescent properties of 2 have been investigated.

  20. Bright luminescence in lanthanide coordination polymers with tetrafluoroterephthalate as a bridging ligand.

    PubMed

    Sobieray, Miriam; Gode, Jens; Seidel, Christiane; Poß, Marieke; Feldmann, Claus; Ruschewitz, Uwe

    2015-04-01

    Ten new coordination polymers of the general compositions ?²[Ln(III)(tfBDC)(NO3)(DMF)2]·DMF with Ln(III) = Eu(3+) (1), Gd(3+) (2), Tb(3+) (3), Ho(3+) (4), Tm(3+) (5), ?²[Ln(III)(tfBDC)(CH3COO)(FA)3]·3FA with Ln(III) = Sm(3+) (6), Eu(3+) (7) and ?²[Ln(III)(tfBDC)(NO3)(DMSO)2] with Ln(III) = Ho(3+) (8), Er(3+) (9) and Tm(3+) (10) were synthesized and structurally characterized by X-ray single crystal diffraction (tfBDC(2-) = 2,3,5,6-tetrafluoroterephthalate, DMF = N,N'-dimethylformamide, FA = formamide, DMSO = dimethyl sulfoxide). 1-5 crystallize in the monoclinic space group C2/c with Z = 8, 6 and 7 in P1? with Z = 2 and 8-10 in Pbca with Z = 8. All crystal structures contain binuclear lanthanide nodes that are connected by 2,3,5,6-tetrafluoroterephthalates (tfBDC(2-)) to form two-dimensional polymeric structural units. Despite this common structural feature the coordination within these binuclear units is quite different in detail, e.g. CN = 9 for 1-7 and CN = 8 for 8-10. The emission spectra of the europium (1, 7) and terbium (3) compounds reveal bright red and green emission in the visible region. The resulting high quantum yields of 53% (1) and 67% (3) at room temperature show that the replacement of organic ligands with C-H groups by perfluorinated ligands leads to compounds with intense emission, as vibrational quenching is reduced. On the other hand, the influence of the coordinating solvent and additional ligands cannot be neglected, as the replacement of DMF by FA and NO3(-) by CH3COO(-) in 7 leads to a reduced quantum yield of only 10%. Thermoanalytical investigations show that all compounds are stable up to 100-150 °C, before a stepwise release of solvent molecules starts followed by a decomposition of the coordination polymer. PMID:25740408

  1. Anion-controlled assembly of silver-di(aminophenyl)sulfone coordination polymers: Syntheses, crystal structures, and solid state luminescence

    SciTech Connect

    Zhang, Qi-Long; Hu, Peng; Zhao, Yi; Feng, Guang-Wei; Zhang, Yun-Qian; Zhu, Bi-Xue; Tao, Zhu

    2014-02-15

    Five silver coordination polymers, namely, ([Ag(3,3?-daps){sub 2}]·BF{sub 4}){sub n} (1), ([Ag(3,3?-daps){sub 2}]·NO{sub 3}){sub n} (2), [Ag(3,3?-daps)(CF{sub 3}SO{sub 3})]{sub n} (3), ([Ag(4,4?-daps)]·CF{sub 3}SO{sub 3}){sub n} (4), and ([Ag(4,4?-daps)]·ClO{sub 4}){sub n} (5) (3,3?-daps=di(3?-aminodiphenyl)sulfone, and 4,4?-daps=di(4?-aminodiphenyl)sulfone) have been synthesized and structural characterized by elemental analyses, IR spectra, powder X-ray diffraction (PXRD) and single-crystal X-ray diffraction analyses. Complex 1 displays a 1D ladder-like chain with four-connected Ag ions and bridged 3,3?-daps. Complex 2 shows other 1D ladder chain modified by tentacles. Complex 3 is a 2D layer structure with both Ag ions and 3,3?-daps are 3-connected nodes. Complex 4 is another 1D ladder chain with three-connected Ag ions and 4,4?-daps. Complex 5 shows a 2D 4{sup 4}-sql net with Ag ions and 4,4?-daps as 4-connected nodes. Moreover, their solid state luminescence and thermal stabilities also have been investigated. - Graphical abstract: Pictogram: Synthetic procedures of the five anion controlled silver coordination polymers. We reported the synthetic procedures, structure, and luminescence property of the five anion controlled silver coordination polymers based on two novel di(aminophenyl)sulfone V-shaped ligands. Display Omitted - Highlights: • Five new silver coordination polymers were synthesized and characterized. • Two novel designed V-shaped di(aminophenyl)sulfone ligands were first introduced to coordination chemistry. • Anions play important roles in determining the five silver coordination polymers. • The structural diversity and photoluminescence property were also discussed.

  2. Two new luminescent Zn(II) coordination polymers with different interpenetrated motifs

    NASA Astrophysics Data System (ADS)

    Song, Changying; Liu, Qifeng; Liu, Wei; Cao, Ziqing; Ren, Yuanyuan; Zhou, Qichao; Zhang, Li

    2015-11-01

    Solvothermal reactions of Zn(NO3)2, H2tdc and bib in the presence of different solvents (DMF = N,N'- dimethylformamide or DMA = N,N'- dimethylacetamide) have given rise to two new coordination polymers, namely [Zn2(tdc)2(bib)2]n·2n(H2O) (1) and [Zn(tdc)(bib)0.5(H2O)]n (2) (H2tdc = 2,5-thiophenedicarboxylic acid, bib = 1, 4-bis(imidazolyl)butane). The structures were determined by single crystal X-ray diffraction and characterized by elemental analysis, powder X-ray diffraction and infrared spectroscopy. Compound 1 exhibits a 4-fold interpenetrated dia topological network, and compound 2 features a 8-fold interpenetrated ths topological network. In addition, thermal stabilities and solid state luminescent properties of these two compounds were also investigated.

  3. Pressure-induced amorphization of a dense coordination polymer and its impact on proton conductivity

    SciTech Connect

    Umeyama, Daiki; Hagi, Keisuke; Ogiwara, Naoki; Horike, Satoshi E-mail: kitagawa@icems.kyoto-u.ac.jp; Tassel, Cedric; Kageyama, Hiroshi; Higo, Yuji; Kitagawa, Susumu E-mail: kitagawa@icems.kyoto-u.ac.jp

    2014-12-01

    The proton conductivity of a dense coordination polymer (CP) was investigated under high-pressure conditions. Impedance measurements under high pressures revealed that the proton conductivity of the CP decreased more than 1000-fold at pressures of 3–7 GPa and that the activation energy for proton conduction almost doubled compared with that at ambient pressure. A synchrotron X-ray study under high pressure identified the amorphization process of the CP during compression, which rationally explains the decrease in conductivity and increase in activation energy. This phenomenon is categorized as reversible pressure-induced amorphization of a dense CP and is regarded as a demonstration of the coupling of the mechanical and electrical properties of a CP.

  4. Linear alkaline earth metal phosphinate coordination polymers: synthesis and structural characterization.

    PubMed

    Rood, Jeffrey A; Huttenstine, Ashley L; Schmidt, Zachery A; White, Michael R; Oliver, Allen G

    2014-06-01

    Reaction of alkaline earth metal salts with diphenylphosphinic acid in dimethylformamide solvent afforded four coordination polymers: [Mg3(O2PPh2)6(DMF)2]·2DMF (I), [Ca(O2PPh2)2(DMF)2] (II), [Sr(O2PPh2)2(DMF)2] (III) and [Ba(O2PPh2)2(DMF)2] (IV) (where DMF is N,N-dimethylformamide). Single-crystal X-ray diffraction revealed that all four compounds produce linear chain structures in the solid state, with the Ca, Sr and Ba forming isostructural crystals. The bulk materials were characterized by FT-IR and (1)H NMR spectroscopy and elemental analyses. PMID:24892607

  5. Fast and persistent electrocatalytic water oxidation by Co-Fe Prussian blue coordination polymers.

    PubMed

    Pintado, Sara; Goberna-Ferrón, Sara; Escudero-Adán, Eduardo C; Galán-Mascarós, José Ramón

    2013-09-11

    The lack of an efficient, robust, and inexpensive water oxidation catalyst (WOC) is arguably the biggest challenge for the technological development of artificial photosynthesis devices. Here we report the catalytic activity found in a cobalt hexacyanoferrate (CoHCF) Prussian blue-type coordination polymer. This material is competitive with state-of-the-art metal oxides and exhibits an unparalleled long-term stability at neutral pH and ambient conditions, maintaining constant catalytic rates for weeks. In addition to its remarkable catalytic activity, CoHCF adds the typical properties of molecule-based materials: transparency to visible light, porosity, flexibility, processability, and low density. Such features make CoHCF a promising WOC candidate for advancement in solar fuels production. PMID:23978044

  6. Substituent-induced effects on dimensionality in cadmium isophthalate coordination polymers containing 3-pyridylisonicotinamide

    NASA Astrophysics Data System (ADS)

    O'Donovan, Megan E.; Wudkewych, Megan J.; LaDuca, Robert L.

    2015-08-01

    Hydrothermal treatment of cadmium nitrate, a 5-substituted isophthalic acid, and 3-pyridylisonicotinamide (3-pina) resulted in three coordination polymers whose dimensionality depended critically on the nature of the aromatic ring substituent. These three new phases were characterized by single crystal X-ray diffraction. {[Cd(hip)(3-pina)(H2O)2]·2H2O}n (1, hip = 5-hydroxyisophthalate) and {[Cd(meoip)(3-pina)(H2O)2]·H2O}n (2, meoip = 5-methoxyisophthalate) both manifest simple 1-D chain structures with pendant 3-pina ligands. [Cd(mip)(3-pina)]n (3, mip = 5-methylisophthalate) possesses [Cd(mip)]n 1-D chains featuring {Cd2(OCO)2} dimeric units, linked by tethering 3-pina ligands into a non-interpenetrated 3-D 6-connected 41263 pcu network. Luminescent behavior in all cases is attributed to intra-ligand molecular orbital transitions.

  7. A novel copper(II) coordination polymer with carboxylate and isoindol backbones of a bifunctional ligand

    NASA Astrophysics Data System (ADS)

    Patra, Ayan; Sen, Tamal K.; Musie, Ghezai T.; Mandal, Swadhin K.; Bera, Manindranath

    2013-09-01

    The reaction of a bifunctional ligand, 3-(1-oxo-1,3-dihydro-isoindol-2-yl)-propionic acid (Hpda) with Cu(NO3)2?3H2O in methanol-water in the presence of NaOH at room temperature produces a novel dinuclear copper(II) coordination polymer [Cu2(pda)4]n. The complex is fully characterized in the solid state as well as in solution using various analytical techniques including single crystal X-ray diffraction study. The single crystal X-ray structure analysis reveals that the monomeric unit of complex consists of Cu2(O2CR)4 paddlewheel building unit, where the two copper centers acquire a distorted square pyramidal geometry with amide oxygen of the isoindol ring of an adjacent Hpda ligand sitting on the axial positions.

  8. Pressure Sensor via Optical Detection Based on a 1D Spin Transition Coordination Polymer

    PubMed Central

    Jureschi, C?t?lin M.; Linares, Jorge; Rotaru, Aurelian; Ritti, Marie Hélène; Parlier, Michel; Dîrtu, Marinela M.; Wolff, Mariusz; Garcia, Yann

    2015-01-01

    We have investigated the suitability of using the 1D spin crossover coordination polymer [Fe(4-(2?-hydroxyethyl)-1,2,4-triazole)3]I2·H2O, known to crossover around room temperature, as a pressure sensor via optical detection using various contact pressures up to 250 MPa. A dramatic persistent colour change is observed. The experimental data, obtained by calorimetric and Mössbauer measurements, have been used for a theoretical analysis, in the framework of the Ising-like model, of the thermal and pressure induced spin state switching. The pressure (P)-temperature (T) phase diagram calculated for this compound has been used to obtain the P-T bistability region. PMID:25621610

  9. Hydrothermal synthesis, crystal structure and photoluminescence of two homochiral zinc(II) coordination polymers.

    PubMed

    Ying, Shao-Ming; Ru, Jing-Jing; Luo, Wu-Kui

    2015-07-01

    Metal-organic frameworks (MOFs) have potentially useful applications and an intriguing variety of architectures and topologies. Two homochiral coordination polymers have been synthesized by the hydrothermal method, namely poly[(?-N-benzyl-L-phenylalaninato-?(4)O,O':O,N)(?-formato-?(2)O:O')zinc(II)], [Zn(C16H16NO2)(HCOO)]n, (1), and poly[(?-N-benzyl-L-leucinato-?(4)O,O':O,N)(?-formato-?(2)O:O')zinc(II)], [Zn(C13H18NO2)(HCOO)]n, (2), and studied by single-crystal X-ray diffraction, elemental analyses, IR spectroscopy and fluorescence spectroscopy. Compounds (1) and (2) each have a two-dimensional layer structure, with the benzyl or isobutyl groups of the ligands directed towards the interlayer interface. Photoluminescence investigations show that both (1) and (2) display a strong emission in the blue region. PMID:26146402

  10. Long-Range Ferromagnetic Ordering in Two-Dimensional Coordination Polymers Co[N(CN)2]2(L) [L ) Pyrazine Dioxide (pzdo) and 2-Methyl

    E-print Network

    Gao, Song

    Laboratory of Rare Earth Materials Chemistry and Applications, PKU-HKU Joint Laboratory on Rare Earth, which offer rare examples of mixed 1,5-µ- and µ3-dca bridging coordination polymers with long-range ferromagnetic ordering below ca. 2.5 K. The design and synthesis of metal coordination polymers are currently

  11. Four homochiral coordination polymers contain N-acetyl-L-tyrosine and different N-donor ligand: Influence of metal cations, ancillary ligands and coordination modes

    SciTech Connect

    Li, Meng-Li; Song, Hui-Hua

    2013-10-15

    Using the chiral ligand N-acetyl-L-tyrosine (Hacty) and maintaining identical reaction conditions, Zn(II), Co(II), and Cd(II) salts provided four novel homochiral coordination polymers ([Zn(acty)(bipy){sub 2}(H{sub 2}O){sub 2}]·NO{sub 3}·2H{sub 2}O){sub n}1, ([Co(acty)(bipy){sub 2}(H{sub 2}O){sub 2}]·NO{sub 3}·2H{sub 2}O){sub n}2, ([Cd(acty){sub 2}(bipy)H{sub 2}O]·H{sub 2}O){sub n}3, and ([Cd(acty)(bpe){sub 2}(Ac)]·6H{sub 2}O){sub n}4 (bipy=4,4?-bipyridine; bpe=1,2-di(4-pyridyl)ethane) in the presence of ancillary ligands. Compounds 1 and 2 are isostructural 1D chain structures. The neighboring chains are further linked into a 3D supramolecular structure via ??? stacking and hydrogen bond interactions. Compound 3 shows a 2D network and 4 generates 1D infinite chains along the c-axis. Compounds 3 and 4 are further connected into 3D supramolecular network by hydrogen bond interactions. More importantly, coordination in acyl oxygen atoms and ancillary ligands (bpe) as monodentate decorating ligands in 4 are rarely reported. Ancillary ligands and metal cations significantly influence the structure of the complexes. The photoluminescence properties of 1, 3, and 4 were studied at room temperature. Circular dichroism (CD) of the complexes have been investigated. - Graphical abstract: Four new homochiral coordination polymers were prepared and structurally characterized, which investigate the influence of the ancillary ligands and metal ions on the design and synthesis of coordination polymers. Display Omitted - Highlights: • It is rarely reported that the chiral coordination polymers prepared with N-acetyl-L-tyrosine ligands. • The alkalescent acetyl oxygen atom is difficult to participate in coordination but it is happened in the N-acetyl-L-tyrosine ligands. • The ancillary ligands (4,4?-bipy and bpe) are present in an unusual coordination modes, monodentate decorating ligands in 1, 2 and 4. • Structure comparative analyses results indicate that the secondary ligands and metal ions influence the fabrication of these inorganic–organic arrangements.

  12. Studies of the structural and magnetic properties of an unsymmetrical ligand 1,2,4-benzenetricarboxylic acid based chiral 3-D trinickel coordination polymer as an alkali base-influenced hydrothermal reaction product

    SciTech Connect

    Peng, Yi-Ru; Chien, Po-Hsiu; Chung, Huey-Ting; Pan, Pei-Yun; Liu, Yen-Hsiang Yang, En-Che

    2014-04-01

    The reaction of 1,2,4-benzenetricarboxylic acid (H{sub 3}btc), as a ligand, under pH-controlled hydrothermal conditions with nickel salts leads to the formation of a coordination polymer of (CsNi{sub 3}(OH)(H{sub 2}O){sub 3}[C{sub 6}H{sub 3}(CO{sub 2}){sub 3}]{sub 2}·3H{sub 2}O){sub n} (1). The subunit of compound 1 contains a hydroxide- and carboxylate-bridged trinickel clusters that are linked by an unsymmetrical organic carboxylate spacer to form a chiral three-dimensional anionic framework, in which cesium cations and guest water molecules are located in one-dimensional channels. The presence of a hydroxide ion serves both as a deprotonation agent and a cation source during the hydrothermal reaction, thus permitting the extent of deprotonation of the unsymmetrical ligand H{sub 3}btc to be controlled, which is essential for the successful formation of compound 1. The magnetic properties of compound 1 were analyzed. Both dc and ac magnetic susceptibility as well as reduced magnetization measurements confirmed the spin-frustration nature of 1. - Graphical abstract: A chiral three-dimension MOF compound and its magnetic properties are described. - Highlights: • A new chiral three-dimension coordination polymer were made. • An un-symmetric bridging ligand was used. • Alkali metal ion Cs{sup +} was incorporated in the structure. • Magnetic properties were studied.

  13. Stereoselectivity in metallocene-catalyzed coordination polymerization of renewable methylene butyrolactones: from stereo-random to stereo-perfect polymers.

    PubMed

    Chen, Xia; Caporaso, Lucia; Cavallo, Luigi; Chen, Eugene Y-X

    2012-05-01

    Coordination polymerization of renewable ?-methylene-?-(methyl)butyrolactones by chiral C(2)-symmetric zirconocene catalysts produces stereo-random, highly stereo-regular, or perfectly stereo-regular polymers, depending on the monomer and catalyst structures. Computational studies yield a fundamental understanding of the stereocontrol mechanism governing these new polymerization reactions mediated by chiral metallocenium catalysts. PMID:22524267

  14. Synthesis of Nanoporous Ni-Co Mixed Oxides by Thermal Decomposition of Metal-Cyanide Coordination Polymers.

    PubMed

    Zakaria, Mohamed B; Hu, Ming; Pramanik, Malay; Li, Cuiling; Tang, Jing; Aldalbahi, Ali; Alshehri, Saad M; Malgras, Victor; Yamauchi, Yusuke

    2015-07-01

    A straightforward strategy to prepare nanoporous metal oxides with well-defined shapes is highly desirable. Through thermal treatment and a proper selection of metal-cyanide coordination polymers, nanoporous nickel-cobalt mixed oxides with different shapes (i.e., flakes and cubes) can be easily prepared. Our nanoporous materials demonstrate high electrocatalytic activity for oxygen evolution reaction. PMID:25968597

  15. Divergent layer topologies in divalent metal aliphatic dicarboxylate coordination polymers containing 3-pyridylmethylnicotinamide

    NASA Astrophysics Data System (ADS)

    White, Charmaine L.; Torres Salgado, Maria D.; Mizzi, Jessica E.; LaDuca, Robert L.

    2015-12-01

    Hydrothermal reaction of the requisite metal salt, an aliphatic dicarboxylic acid, and the hydrogen-bonding capable dipyridylamide ligand 3-pyridylmethylnicotinamide (3-pmna) resulted in four coordination polymers whose connectedness and layer topology depend on the metal coordination environment and dicarboxylate binding mode. These new crystalline phases were characterized by single crystal X-ray diffraction. [Cu(ox)(3-pmna)]n (1, ox = oxalate) manifests stacked 3-connected (6,3) herringbone layer motifs. {[Cd(mal)(3-pmna)(H2O)]·3H2O}n (2, mal = malonate) shows a 4-connected (4,4) grid topology with entrained water molecule trimeric chains in the interlamellar regions. {[Cd2(suc)2(3-pmna)(H2O)2]·3H2O}n (3, suc = succinate) possesses {Cd2O2} dimer-based [Cd(suc)]n layers pillared by 3-pmna ligands into a 5-connected sandwich motif with 4862 topology. {[Cd(glu)(3-pmna)(H2O)]·3H2O}n (4, glu = glutarate) manifests a rippled (4,4) grid topology. Luminescent behavior in the cadmium complexes is ascribed to intra-ligand molecular orbital transitions. Thermal decomposition behavior is also discussed herein.

  16. Gram-scale synthesis of coordination polymer nanodots with renal clearance properties for cancer theranostic applications

    NASA Astrophysics Data System (ADS)

    Liu, Fuyao; He, Xiuxia; Chen, Hongda; Zhang, Junping; Zhang, Huimao; Wang, Zhenxin

    2015-08-01

    An ultrasmall hydrodynamic diameter is a critical factor for the renal clearance of nanoparticles from the body within a reasonable timescale. However, the integration of diagnostic and therapeutic components into a single ultrasmall nanoparticle remains challenging. In this study, pH-activated nanodots (termed Fe-CPNDs) composed of coordination polymers were synthesized via a simple and scalable method based on coordination reactions among Fe3+, gallic acid and poly(vinylpyrrolidone) at ambient conditions. The Fe-CPNDs exhibited ultrasmall (5.3 nm) hydrodynamic diameters and electrically neutral surfaces. The Fe-CPNDs also exhibited pH-activatable magnetic resonance imaging contrast and outstanding photothermal performance. The features of Fe-CPNDs greatly increased the tumour-imaging sensitivity and facilitated renal clearance after injection in animal models in vivo. Magnetic resonance imaging-guided photothermal therapy using Fe-CPNDs completely suppressed tumour growth. These findings demonstrate that Fe-CPNDs constitute a new class of renal clearable nanomedicine for photothermal therapy and molecular imaging.

  17. Plasmonic photocatalytic reactions enhanced by hot electrons in a one-dimensional quantum well

    NASA Astrophysics Data System (ADS)

    Huang, H. J.; Liu, B.-H.; Lin, C.-T.; Su, W. S.

    2015-11-01

    The plasmonic endothermic oxidation of ammonium ions in a spinning disk reactor resulted in light energy transformation through quantum hot charge carriers (QHC), or quantum hot electrons, during a chemical reaction. It is demonstrated with a simple model that light of various intensities enhance the chemical oxidization of ammonium ions in water. It was further observed that light illumination, which induces the formation of plasmons on a platinum (Pt) thin film, provided higher processing efficiency compared with the reaction on a bare glass disk. These induced plasmons generate quantum hot electrons with increasing momentum and energy in the one-dimensional quantum well of a Pt thin film. The energy carried by the quantum hot electrons provided the energy needed to catalyze the chemical reaction. The results indicate that one-dimensional confinement in spherical coordinates (i.e., nanoparticles) is not necessary to provide an extra excited state for QHC generation; an 8 nm Pt thin film for one-dimensional confinement in Cartesian coordinates can also provide the extra excited state for the generation of QHC.

  18. One dimensional speckle fields generated by three phase level diffusers

    NASA Astrophysics Data System (ADS)

    Cabezas, L.; Amaya, D.; Bolognini, N.; Lencina, A.

    2015-02-01

    Speckle patterns have usually been obtained by using ground glass as random diffusers. Liquid-crystal spatial light modulators have opened the possibility of engineering tailored speckle fields obtained from designed diffusers. In this work, one-dimensional Gaussian speckle fields with fully controllable features are generated. By employing a low-cost liquid-crystal spatial light modulator, one-dimensional three phase level diffusers are implemented. These diffusers make it possible to control average intensity distribution and statistical independence among the generated patterns. The average speckle size is governed by an external slit pupil. A theoretical model to describe the generated speckle patterns is developed. Experimental and theoretical results confirming the generation of one-dimensional speckle fields are presented. Some possible applications of these speckles, such as atom trapping and super-resolution imaging, are briefly envisaged.

  19. Hydrothermal reactions: From the synthesis of ligand to new lanthanide 3D-coordination polymers

    SciTech Connect

    Silva, Fausthon Fred da; Fernandes de Oliveira, Carlos Alberto; Lago Falcão, Eduardo Henrique; Gatto, Claudia Cristina; Bezerra da Costa, Nivan; Oliveira Freire, Ricardo; Chojnacki, Jaros?aw; Alves Júnior, Severino

    2013-11-15

    The organic ligand 2,5-piperazinedione-1,4-diacetic acid (H{sub 2}PDA) was synthesized under hydrothermal conditions starting from the iminodiacetic acid and catalyzed by oxalic acid. The X-ray powder diffraction data indicates that the compound crystallizes in the P2{sub 1}/c monoclinic system as reported in the literature. The ligand was also characterized by elemental analysis, magnetic nuclear resonance, infrared spectroscopy and thermogravimetric analysis. Two new coordination networks based on lanthanide ions were obtained with this ligand using hydrothermal reaction. In addition to single-crystal X-ray diffraction, the compounds were characterized by infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy and elemental analysis. Single-crystal XRD showed that the compounds are isostructural, crystallizing in P2{sub 1}/n monoclinic system with chemical formula [Ln(PDA){sub 1.5}(H{sub 2}O)](H{sub 2}O){sub 3} (Ln=Gd{sup 3+}(1) and Eu{sup 3+}(2)).The luminescence properties of both compounds were studied. In the compound (1), a broad emission band was observed at 479 nm, redshifted by 70 nm in comparison of the free ligand. In (2), the typical f–f transition was observed with a maximum peak at 618 nm, related with the red emission of the europium ions. Computational methods were performed to simulate the crystal structure of (2). The theoretical calculations of the intensity parameters are in good agreement with the experimental values. - Graphical abstract: Scheme of obtaining the ligand 2,5-piperazinedione-1,4-diacetic acid (H{sub 2}PDA) and two new isostructural 3D-coordination polymers [Ln(PDA){sub 1.5}(H{sub 2}O)](H{sub 2}O){sub 3} (Ln=Gd{sup 3+} and Eu{sup 3+}) by hydrothermal synthesis. Display Omitted - Highlights: • The ligand 2,5-piperazinedione-1,4-diacetic acid was synthetized using the hydrothermic method and characterized. • Two new 3D-coordination polymers with this ligand containing Gd{sup 3+} and Eu{sup 3+} ions were also obtained. • The compounds are isostructural and the typical luminescent properties were observed in both structures.

  20. Equilibration of a one-dimensional quantum liquid

    SciTech Connect

    Matveev, K. A.

    2013-09-15

    We review some of the recent results on equilibration of one-dimensional quantum liquids. The low-energy properties of these systems are described by the Luttinger liquid theory, in which the excitations are bosonic quasiparticles. At low temperatures, the relaxation of the gas of excitations toward full equilibrium is exponentially slow. In electronic Luttinger liquids, these relaxation processes involve backscattering of electrons and give rise to interesting corrections to the transport properties of one-dimensional conductors. We focus on the phenomenological theory of the equilibration of a quantum liquid and obtain an expression for the relaxation rate in terms of the excitation spectrum.

  1. Exact canonically conjugate momenta approach to a one-dimensional neutron-proton system, I

    NASA Astrophysics Data System (ADS)

    Nishiyama, Seiya; da Providência, João

    2015-06-01

    Introducing collective variables, a collective description of nuclear surface oscillations has been developed with the first-quantized language, contrary to the second-quantized one in Sunakawa's approach for a Bose system. It overcomes difficulties remaining in the traditional theories of nuclear collective motions: Collective momenta are not exact canonically conjugate to collective coordinates and are not independent. On the contrary to such a description, Tomonaga first gave the basic idea to approach elementary excitations in a one-dimensional Fermi system. The Sunakawa's approach for a Fermi system is also expected to work well for such a problem. In this paper, on the isospin space, we define a density operator and further following Tomonaga, introduce a collective momentum. We propose an exact canonically momenta approach to a one-dimensional neutron-proton (N-P) system under the use of the Grassmann variables.

  2. A three-dimensional CdII coordination polymer constructed from 1,1'-biphenyl-2,2',5,5'-tetracarboxylate and 1,4-bis(1H-imidazol-1-yl)benzene ligands.

    PubMed

    Su, Feng; Lu, Li-Ping

    2015-07-01

    The title coordination polymer, poly[[aqua(?5-1,1'-biphenyl-2,2',5,5'-tetracarboxylato)bis[?2-1,4-bis(1H-imidazol-1-yl)benzene]dicadmium(II)] dihydrate], {[Cd2(C16H6O8)(C12H10N4)2(H2O)]·2H2O}n, was crystallized from a mixture of 1,1'-biphenyl-2,2',5,5'-tetracarboxylic acid (H4bpta), 1,4-bis(1H-imidazol-1-yl)benzene (1,4-bib) and cadmium nitrate in water-dimethylformamide. The crystal structure consists of two crystallographically independent Cd(II) cations, with one of the Cd(II) cations possessing a slightly distorted pentagonal bipyramidal geometry. The second Cd(II) centre is coordinated by carboxylate O atoms and imidazole N atoms from two separate 1,4-bib ligands, displaying a distorted octahedral CdN2O4 geometry. The completely deprotonated bpta(4-) ligand, exhibiting a new coordination mode, bridges five Cd(II) cations to form one-dimensional chains via ?3-?(1):?(2):?(1):?(2) and ?2-?(1):?(1):?(0):?(0) modes, and these are further linked by 1,4-bib ligands to form a three-dimensional framework with a (4(2).6(4))(4.6(2))(4(3).6(5).7(2)) topology. The structure of the coordination polymer is reinforced by intermolecular hydrogen bonding between carboxylate O atoms, aqua ligands and crystallization water molecules. The solid-state photoluminescence properties were investigated and the complex might be a candidate for a thermally stable and solvent-resistant blue fluorescent material. PMID:26146389

  3. Mathematical modeling of quasi-one-dimensional hemodynamics

    NASA Astrophysics Data System (ADS)

    Bunicheva, A. Ya.; Mukhin, S. I.; Sosnin, N. V.; Khrulenko, A. B.

    2015-08-01

    New unpublished results of research conducted under the guidance of Prof. Favorskii at the Chair of Computational Methods of Moscow State University are presented. Justification and implementation of a quasi-one-dimensional approximation for mathematical modeling of hemodynamics are discussed.

  4. Toward precise solution of one-dimensional velocity inverse problems

    SciTech Connect

    Gray, S.; Hagin, F.

    1980-01-01

    A family of one-dimensional inverse problems are considered with the goal of reconstructing velocity profiles to reasonably high accuracy. The travel-time variable change is used together with an iteration scheme to produce an effective algorithm for computation. Under modest assumptions the scheme is shown to be convergent.

  5. Impurity-induced polaritons in a one-dimensional chain

    E-print Network

    Yamilov, Alexey

    Impurity-induced polaritons in a one-dimensional chain Alexey Yamilov Department of Physics, Queens-induced polariton band arising inside a spectral gap between lower and upper polariton branches is presented. Using the microcanonical method, we calculate the density of states and the localization length of the impurity polaritons

  6. Approximate Approaches to the One-Dimensional Finite Potential Well

    ERIC Educational Resources Information Center

    Singh, Shilpi; Pathak, Praveen; Singh, Vijay A.

    2011-01-01

    The one-dimensional finite well is a textbook problem. We propose approximate approaches to obtain the energy levels of the well. The finite well is also encountered in semiconductor heterostructures where the carrier mass inside the well (m[subscript i]) is taken to be distinct from mass outside (m[subscript o]). A relevant parameter is the mass…

  7. Quantum circuits for solving one-dimensional Schrödinger equations

    E-print Network

    K. Nakao; A. Matsuyama

    2009-07-20

    We construct quantum circuits for solving one-dimensional Schr\\"odinger equations. Simulations of three typical examples, i.e., harmonic oscillator, square-well and Coulomb potential, show that reasonable results can be obtained with eight qubits. Our simulations show that simple quantum circuits can solve the standard quantum mechanical problems.

  8. Ground State Entanglement in One Dimensional Translationally Invariant Quantum Systems

    E-print Network

    Irani, Sandy

    Ground State Entanglement in One Dimensional Translationally Invariant Quantum Systems Sandy Irani and quantifying entanglement in quantum systems is a central theme in quantum information science. On one hand quantum entanglement is a valuable re- source that enables novel computation and communication

  9. One-Dimensional SO2 Predictions for Duct Injection

    Energy Science and Technology Software Center (ESTSC)

    1993-10-05

    DIAN1D is a one-dimensional model that predicts SO2 absorption by slurry droplets injected into a flue gas stream with two-fluid atomizers. DIANUI is an interactive user interface for DIAN1D. It prepares the input file for DIAN1D from plant design specifications and process requirements.

  10. TOPOLOGICAL ENTROPY FOR MULTIDIMENSIONAL PERTURBATIONS OF ONE-DIMENSIONAL MAPS

    E-print Network

    Zgliczynski, Piotr

    TOPOLOGICAL ENTROPY FOR MULTIDIMENSIONAL PERTURBATIONS OF ONE-DIMENSIONAL MAPS Michal Misiurewicz that if an interval map of positive entropy is per- turbed to a compact multidimensional map then the topological and phrases. Interval maps, Multidimensional perturbations, Topological entropy, Horseshoes. 1 #12;2 M

  11. SIMPLE ONE-DIMENSIONAL TRANSPORT CODE FOR MAGNETIZED TARGET FUSION

    SciTech Connect

    STEFANO MIGLUIOLO - MIT

    1999-10-30

    A one-dimensional (in space) time-dependent simulation code is development to study the transport of energy and particles in a field reversed configuration (FRC) plasma that is undergoing radial contraction. This contraction is due to an imploding metallic liner, which is treated through a boundary condition.

  12. ACOUSTIC WAVE TRAPPING IN ONE-DIMENSIONAL AXISYMMETRIC ARRAYS

    E-print Network

    ACOUSTIC WAVE TRAPPING IN ONE- DIMENSIONAL AXISYMMETRIC ARRAYS by M. MCIVER (Department 2011. Revise 2011] Summary The existence of acoustic, Rayleigh-Bloch modes in the vicinity of a one for the acoustic wave-field in the neighbourhood of such an array is obtained and solved with the use of a Galerkin

  13. Sandia One-Dimensional Direct and Inverse Thermal Code

    Energy Science and Technology Software Center (ESTSC)

    1995-02-27

    SODDIT is a reliable tool for solving a wide variety of one-dimensional transient heat conduction problems. Originally developed in 1972 to predict the ablation of graphite/carbon bodies reentering the earth''s atmosphere, it has since been modified by the authors to extend its capabilities well beyond its original scope.

  14. Splendid One-Dimensional Nanostructures of Zinc Oxide: A New

    E-print Network

    Wang, Zhong L.

    , silicon nanowires, and ZnO nanowires/nanobelts are probably the most important 1-D nanomaterials in to candidate for sensors, transduc- ers, energy generators, and photocatalysts for hydrogen production. Zn in 2001.4 As for one-dimensional (1-D) nanostructures, ZnO has equal impor- tance to silicon-based 1-D

  15. One-Dimensional Ising Model with "k"-Spin Interactions

    ERIC Educational Resources Information Center

    Fan, Yale

    2011-01-01

    We examine a generalization of the one-dimensional Ising model involving interactions among neighbourhoods of "k" adjacent spins. The model is solved by exploiting a connection to an interesting computational problem that we call ""k"-SAT on a ring", and is shown to be equivalent to the nearest-neighbour Ising model in the absence of an external…

  16. The Long Decay Model of One-Dimensional Projectile Motion

    ERIC Educational Resources Information Center

    Lattery, Mark Joseph

    2008-01-01

    This article introduces a research study on student model formation and development in introductory mechanics. As a point of entry, I present a detailed analysis of the Long Decay Model of one-dimensional projectile motion. This model has been articulated by Galileo ("in De Motu") and by contemporary students. Implications for instruction are…

  17. UncorrectedProof Nanoscale Testing of One-Dimensional

    E-print Network

    Espinosa, Horacio D.

    computational predictions. AQ: Please provide Email address for Author "Y. Zhu, Y.G. Sun and H.-H. WangUncorrectedProof Chapter 11 Nanoscale Testing of One-Dimensional Nanostructures B. Peng, Y.G. Sun, Y. Zhu, H.-H. Wang, and H.D. Espinosa AQ: Please expand Author's initials. 11.1 Introduction

  18. Teaching Module for One-Dimensional, Transient Conduction.

    ERIC Educational Resources Information Center

    Ribando, Robert J.; O'Leary, Gerald W.

    1998-01-01

    Describes a PC-based teaching module designed to instruct engineering students in transient one-dimensional conduction heat transfer analysis. The discussion considers problem formulation, nondimensionalization, discretization, numerical stability and the time-step restriction, program operation, and program verification. (MES)

  19. Ripening of one-dimensional molecular nanostructures on

    E-print Network

    Steinhoff, Heinz-Jürgen

    -based electronic devices, promising material systems are electrical devices based on organic building blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 3 #12;1 Introduction The search of new concepts for building electronic devices goes along]. It is thus desirable to search for organic materials leading to one-dimensional wires, which are, however

  20. Asymptotic velocity of one dimensional diffusions with periodic drift

    E-print Network

    P. Collet S. Martinez

    2007-05-10

    We consider the asymptotic behaviour of the solution of one dimensional stochastic differential equations and Langevin equations in periodic backgrounds with zero average. We prove that in several such models, there is generically a non vanishing asymptotic velocity, despite of the fact that the average of the background is zero.

  1. Underwater striling engine design with modified one-dimensional model

    NASA Astrophysics Data System (ADS)

    Li, Daijin; Qin, Kan; Luo, Kai

    2015-09-01

    Stirling engines are regarded as an efficient and promising power system for underwater devices. Currently, many researches on one-dimensional model is used to evaluate thermodynamic performance of Stirling engine, but in which there are still some aspects which cannot be modeled with proper mathematical models such as mechanical loss or auxiliary power. In this paper, a four-cylinder double-acting Stirling engine for Unmanned Underwater Vehicles (UUVs) is discussed. And a one-dimensional model incorporated with empirical equations of mechanical loss and auxiliary power obtained from experiments is derived while referring to the Stirling engine computer model of National Aeronautics and Space Administration (NASA). The P-40 Stirling engine with sufficient testing results from NASA is utilized to validate the accuracy of this one-dimensional model. It shows that the maximum error of output power of theoretical analysis results is less than 18% over testing results, and the maximum error of input power is no more than 9%. Finally, a Stirling engine for UUVs is designed with Schmidt analysis method and the modified one-dimensional model, and the results indicate this designed engine is capable of showing desired output power.

  2. Fusion for the one-dimensional Hubbard model

    E-print Network

    Niklas Beisert; Marius de Leeuw; Panchali Nag

    2015-03-16

    We discuss a formulation of the fusion procedure for integrable models which is suitable for application to non-standard R-matrices. It allows for construction of bound state R-matrices for AdS/CFT worldsheet scattering or equivalently for the one-dimensional Hubbard model. We also discuss some peculiar cases that arise in these models.

  3. Phase transition of a quasi-one-dimensional system

    NASA Astrophysics Data System (ADS)

    Nyeo, Su-Long; Yang, I.-Ching

    2001-04-01

    The statistical mechanics of the quasi-one-dimensional system of DNA is studied with the Morse and Deng-Fan potentials for the interstrand hydrogen bonds of nucleotide pairs. The intrastrand interactions between nucleotides are characterized by a simple harmonic potential in which the coupling strength has a significant effect on the phase transition of the DNA system.

  4. Metal-Driven Hierarchical Self-Assembled One-Dimensional

    E-print Network

    Huang, Jianbin

    Metal-Driven Hierarchical Self-Assembled One-Dimensional Nanohelices Yan Qiao, Yiyang Lin, Yijie-dimensional helical nanostructure is presented based on metal-cholate supramolecular self-assembly. Well-defined right-handed helical nanoribbons in calcium-cholate systems are systematically investigated and a series of metal ions

  5. Diagnostic Plots for One-Dimensional Data1 G. Sawitzki

    E-print Network

    Diagnostic Plots for One-Dimensional Data1 G. Sawitzki StatLab Heidelberg Im Neuenheimer Feld 294 D: a diagnostic plot is only as good as the hard statistical theory that is supporting it. We try to illustrate this point of view for some examples. Though the general contribution of diagnostic plots to statistics

  6. Structure Determination of the One-Dimensional Compound Sr3ZnPtO6, Containing Zinc in a

    E-print Network

    zur Loye, Hans-Conrad

    Structure Determination of the One-Dimensional Compound Sr3ZnPtO6, Containing Zinc in a HighlyVember 9, 1995 We report the synthesis and structure of a new zinc-containing strontium platinum oxide, Sr3ZnPtO6, in which zinc is present in a highly unusual trigonal prismatic coordination environment

  7. Syntheses, structures and luminescence properties of lanthanide coordination polymers with helical character

    SciTech Connect

    Zhou Ruisha; Cui Xiaobing; Song Jiangfeng; Xu Xiaoyu; Xu Jiqing Wang Tiegang

    2008-08-15

    A series of lanthanide coordination polymers, (Him){sub n}[Ln(ip){sub 2}(H{sub 2}O)]{sub n} [Ln=La(1), Pr(2), Nd(3) and Dy(4), H{sub 2}ip=isophthalic acid, im=imidazole] and [Y{sub 2}(ip){sub 3}(H{sub 2}O){sub 2}]{sub n}.nH{sub 2}O (5), have been synthesized and characterized by elemental analyses, infrared (IR), ultraviolet-visible-near infrared (UV-Vis-NIR) and single-crystal X-ray diffraction analyses. The isostructural compounds 1-4 possess 3-D structures with three different kinds of channels. Compound 5 features a 2-D network making of two different kinds of quadruple-helical chains. Compounds 2 and 3 present the characteristic emissions of Pr(III) and Nd(III) ions in NIR region, respectively. Compound 4 shows sensitized luminescence of Dy(III) ions in visible region. - Graphical abstract: A series of lanthanide coodination polymers, (Him){sub n}[Ln(ip){sub 2}(H{sub 2}O)]{sub n} [Ln=La(1), Pr(2), Nd(3) and Dy(4)] and [Y{sub 2}(ip){sub 3}(H{sub 2}O){sub 2}]{sub n}.nH{sub 2}O (5), have been reported. The isostructural compounds 1-4 possess 3-D structures with three different kinds of channels. Compound 5 displays a 2-D network making of two kinds of quadruple-helical chains. Display Omitted.

  8. Spinons, Solitons, and Breathers in Quasi-One-Dimensional Magnets

    NASA Astrophysics Data System (ADS)

    Broholm, Collin

    2006-03-01

    By scattering neutrons from coordination polymer magnets, we contrast the effects of a uniform and a staggered magnetic field on the quantum critical state of a spin-1/2 chain. In a partially magnetized state of copper pyrazine dinitrate (CuPzN) we find bounded spectral continua indicating that neutrons scatter from spin-1/2 quasi-particle pairs [1]. The complex boundaries including an incommensurate soft spot result from a field induced shift in the Fermi points for these quasi-particles. The measurements indicate that the magnetized state of CuPzN remains quantum critical. Copper benzoate [2] and CuCl2^.2(dimethylsulfoxide) (CDC) [3] differ from CuPzN in that there are two spins per unit cell along the spin chain. Rather than continuous spectra, we find resolution limited gapped excitations when these materials are subject to high fields. So with two spins per unit cell, an applied field can drive the spin-1/2 chain away from criticality. The explanation for this effect was provided by Affleck and Oshikawa. The alternating coordination environment induces a transverse staggered field and spinon binding. The quantum sine-Gordon model is the relevant low energy field theory and it predicts soliton and breather excitations at specific energies and wave vectors that we compare to the experiments. We shall also compare a complete measurement of the dynamic spin correlation function for CDC in a field to exact diagonalization results for a spin-1/2 chain with a staggered and uniform magnetic field [4]. [1] M. B. Stone, D. H. Reich, C. Broholm, K. Lefmann, C. Rischel, C. P. Landee, and M. M. Turnbull, Phys. Rev. Lett. 91, 037205 (2003). [2] M. Kenzelmann, Y. Chien, C. Broholm, D. H. Reich, and Y. Qiu, Phys. Rev. Lett. 93, 017204 (2004). [3] D. C. Dender, P. R. Hammar, Daniel H. Reich, C. Broholm, and G. Aeppli, Phys. Rev. Lett. 79, 1750 (1997). [4] M. Kenzelmann, C. D. Batista, Y. Chen, C. Broholm, D. H. Reich, S. Park, and Y. Qiu, Phys. Rev. B 71, 094411 (2005).

  9. Self-assembled nanoscale coordination polymers with trigger release properties for effective anticancer therapy

    PubMed Central

    Liu, Demin; Poon, Christopher; Lu, Kuangda; He, Chunbai; Lin, Wenbin

    2014-01-01

    Nanoscale coordination polymers (NCPs) are self-assembled from metal ions and organic bridging ligands, and can overcome many drawbacks of existing drug delivery systems by virtue of tunable compositions, sizes, and shapes; high drug loadings; ease of surface modification; and intrinsic biodegradability. Here we report the self-assembly of zinc bisphosphonate NCPs that carry 48±3 wt% cisplatin prodrug and 45±5 wt% oxaliplatin prodrug. In vivo pharmacokinetic studies in mice show minimal uptake of pegylated NCPs by the mononuclear phagocyte system and excellent blood circulation half-lives of 16.4±2.9 and 12.0±3.9 h for the NCPs carrying cisplatin and oxaliplatin, respectively. In all tumor xenograft models evaluated, including CT26 colon cancer, H460 lung cancer, and AsPC-1 pancreatic cancer, pegylated NCPs show superior potency and efficacy compared to free drugs. As the first example of using NCPs as nanotherapeutics with enhanced antitumor activities, this study establishes NCPs as a promising drug delivery platform for cancer therapy. PMID:24964370

  10. Syntheses, structures, and properties of multidimensional lithium coordination polymers based on aliphatic carboxylic acids.

    PubMed

    Cheng, Pei-Chi; Lin, Wei-Cheng; Tseng, Feng-Shuen; Kao, Ching-Che; Chang, Ting-Guang; Senthil Raja, Duraisamy; Liu, Wei-Ren; Lin, Chia-Her

    2013-02-28

    Three lithium coordination polymers, [Li4(H2O)2(EDTA)] (1), [Li4(H2O)4(BTCA)] (2), and (H2NMe2)2[Li2(H2O)2(BTCA)] (3) (H4EDTA = ethylenediaminetetraacetic acid, H4BTCA = 1,2,3,4-butane tetracarboxylic acid, H2NMe2 = dimethyl amine), have been synthesized by reacting lithium salts with aliphatic carboxylic acids using a solvothermal method. The structures of all the three complexes have been determined by single crystal X-ray diffraction studies. The single crystal structure analysis revealed that complex 1 has a three-dimensional framework, whereas complex 2 has 2D sheets and complex 3 has 1D chains. In addition, these lithium complexes contain various inorganic motifs with a tetramer in 1 and 2, and discrete tetrahedra in 3 and have further been connected through organic ligands to construct multidimensional structures. Further, the electrochemical properties of complexes 1–3 have been studied to evaluate these compounds as electrode materials for lithium ion batteries with discharge capacities of around 100 mA h g(-1) in the first thirty cycles. PMID:23235699

  11. Self-assembled nanoscale coordination polymers with trigger release properties for effective anticancer therapy

    NASA Astrophysics Data System (ADS)

    Liu, Demin; Poon, Christopher; Lu, Kuangda; He, Chunbai; Lin, Wenbin

    2014-06-01

    Nanoscale coordination polymers (NCPs) are self-assembled from metal ions and organic bridging ligands, and can overcome many drawbacks of existing drug delivery systems by virtue of tunable compositions, sizes and shapes, high drug loadings, ease of surface modification and intrinsic biodegradability. Here we report the self-assembly of zinc bisphosphonate NCPs that carry 48±3?wt% cisplatin prodrug and 45±5?wt% oxaliplatin prodrug. In vivo pharmacokinetic studies in mice show minimal uptake of pegylated NCPs by the mononuclear phagocyte system and excellent blood circulation half-lives of 16.4±2.9 and 12.0±3.9?h for the NCPs carrying cisplatin and oxaliplatin, respectively. In all tumour xenograft models evaluated, including CT26 colon cancer, H460 lung cancer and AsPC-1 pancreatic cancer, pegylated NCPs show superior potency and efficacy compared with free drugs. As the first example of using NCPs as nanotherapeutics with enhanced antitumour activities, this study establishes NCPs as a promising drug delivery platform for cancer therapy.

  12. Porous coordination polymers as novel sorption materials for heat transformation processes.

    PubMed

    Janiak, Christoph; Henninger, Stefan K

    2013-01-01

    Porous coordination polymers (PCPs)/metal-organic frameworks (MOFs) are inorganic-organic hybrid materials with a permanent three-dimensional porous metal-ligand network. PCPs or MOFs are inorganic-organic analogs of zeolites in terms of porosity and reversible guest exchange properties. Microporous water-stable PCPs with high water uptake capacity are gaining attention for low temperature heat transformation applications in thermally driven adsorption chillers (TDCs) or adsorption heat pumps (AHPs). TDCs or AHPs are an alternative to traditional air conditioners or heat pumps operating on electricity or fossil fuels. By using solar or waste heat as the operating energy TDCs or AHPs can significantly help to minimize primary energy consumption and greenhouse gas emissions generated by industrial or domestic heating and cooling processes. TDCs and AHPs are based on the evaporation and consecutive adsorption of coolant liquids, preferably water, under specific conditions. The process is driven and controlled by the microporosity and hydrophilicity of the employed sorption material. Here we summarize the current investigations, developments and possibilities of PCPs/MOFs for use in low-temperature heat transformation applications as alternative materials for the traditional inorganic porous substances like silica gel, aluminophosphates or zeolites. PMID:23945102

  13. Solvent-dependent zinc(II) coordination polymers with mixed ligands: selective sorption and fluorescence sensing.

    PubMed

    Hua, Ji-Ai; Zhao, Yue; Kang, Yan-Shang; Lu, Yi; Sun, Wei-Yin

    2015-07-01

    Starting from the same metal salts and mixed organic ligands of 1,3,5-tris(1-imidazolyl)benzene (tib) and 2-bromo-1,4-benzenedicarboxylic acid (H2BDC-Br), two novel zinc(II) coordination polymers [Zn2(tib)2(BDC-Br)]2·2SO4·17H2O (1) and [Zn4(tib)2(BDC-Br)3(H2O)4SO4]·7.5H2O·2.5DMF (2) (DMF = N,N-dimethylformamide) were obtained by using different solvent systems of DMF/H2O and DMF/EtOH/H2O, respectively. 1 is an unusual (3,4)-connected 3D net with a Point symbol of {4·8·10(4)}{4·8·10}, while 2 is a complicated 1D chain, which is further connected to form a 3D supramolecular architecture by hydrogen bonding interactions. In particular, 1 and 2 exhibit selective adsorption of CO2 over N2 and show good selectivity for detection of acetone via fluorescence quenching. PMID:26032187

  14. Porous coordination polymers with ubiquitous and biocompatible metals and a neutral bridging ligand

    PubMed Central

    Noro, Shin-ichiro; Mizutani, Junya; Hijikata, Yuh; Matsuda, Ryotaro; Sato, Hiroshi; Kitagawa, Susumu; Sugimoto, Kunihisa; Inubushi, Yasutaka; Kubo, Kazuya; Nakamura, Takayoshi

    2015-01-01

    The design of inexpensive and less toxic porous coordination polymers (PCPs) that show selective adsorption or high adsorption capacity is a critical issue in research on applicable porous materials. Although use of Group II magnesium(II) and calcium(II) ions as building blocks could provide cheaper materials and lead to enhanced biocompatibility, examples of magnesium(II) and calcium(II) PCPs are extremely limited compared with commonly used transition metal ones, because neutral bridging ligands have not been available for magnesium(II) and calcium(II) ions. Here we report a rationally designed neutral and charge-polarized bridging ligand as a new partner for magnesium(II) and calcium(II) ions. The three-dimensional magnesium(II) and calcium(II) PCPs synthesized using such a neutral ligand are stable and show selective adsorption and separation of carbon dioxide over methane at ambient temperature. This synthetic approach allows the structural diversification of Group II magnesium(II) and calcium(II) PCPs. PMID:25592677

  15. Switchable guest molecular dynamics in a perovskite-like coordination polymer toward sensitive thermoresponsive dielectric materials.

    PubMed

    Du, Zi-Yi; Xu, Ting-Ting; Huang, Bo; Su, Yu-Jun; Xue, Wei; He, Chun-Ting; Zhang, Wei-Xiong; Chen, Xiao-Ming

    2015-01-12

    A new perovskite-like coordination polymer [(CH3)2NH2][Cd(N3)3] is reported which undergoes a reversible ferroelastic phase transition. This transition is due to varied modes of motion of the [(CH3)2NH2](+) guest accompanied by a synergistic deformation of the [Cd(N3)3](-) framework. The unusual two-staged switchable dielectric relaxation reveals the molecular dynamics of the polar cation guest, which are well controlled by the variable confined space of the host framework. As the material switches from the ferroelastic phase to the paraelastic phase, a remarkable increase of the rotational energy barrier is detected. As a result, upon heating at low temperature, this compound shows a notable change from a low to a high dielectric state in the ferroelastic phase. This thermoresponsive host-guest system may serve as a model compound for the development of sensitive thermoresponsive dielectric materials and may be key to understanding and modulating molecular/ionic dynamics of guest molecules in confined space. PMID:25430633

  16. How to Define Variation of Physical Properties Normal to an Undulating One-Dimensional Object

    E-print Network

    Hsiao-Ping Hsu; Kurt Binder; Wolfgang Paul

    2009-11-15

    One-dimensional flexible objects are abundant in physics, from polymers to vortex lines to defect lines and many more. These objects structure their environment and it is natural to assume that the influence these objects exert on their environment depends on the distance from the line-object. But how should this be defined? We argue here that there is an intrinsic length scale along the undulating line that is a measure of its "stiffness" (i.e., orientational persistence), which yields a natural way of defining the variation of physical properties normal to the undulating line. We exemplify how this normal variation can be determined from a computer simulation for the case of a so-called bottle-brush polymer, where side chains are grafted onto a flexible backbone.

  17. Explosive Disruption of Polytropes: a One Dimensional Hydrodynamic Calculation

    E-print Network

    Mark Wyman; David Chernoff; Ira Wasserman

    2004-07-27

    We study explosions of stars using a one-dimensional Lagrangian hydrodynamics code. We calculate how much mass is liberated as a function of the energy of explosion for a variety of pre-explosion stellar structures and for equations of state with a range of radiation-to-gas pressure ratios. The results show that simple assumptions about the amount of mass lost in an explosion can be quite inaccurate, and that even one-dimensional stars exhibit a rich phenomenology. The mass loss fraction rises from about 50 to 100 per cent as a function of the explosion energy in an approximately discontinuous manner. Combining our results with those of other, more realistic models, we suggest that Nova Scorpii (J1655-40) may have experienced significant mass fallback because the explosion energy was less than the critical value. We infer that the original progenitor was less than twice the mass of today's remnant.

  18. Scaling properties of one-dimensional driven-dissipative condensates

    NASA Astrophysics Data System (ADS)

    He, Liang; Sieberer, Lukas M.; Altman, Ehud; Diehl, Sebastian

    2015-10-01

    We numerically investigate the scaling properties of a one-dimensional driven-dissipative condensate described by a stochastic complex Ginzburg-Landau equation (SCGLE). We directly extract the static and dynamical scaling exponents from the dynamics of the condensate's phase field, and find that both coincide with the ones of the one-dimensional Kardar-Parisi-Zhang (KPZ) equation. We furthermore calculate the spatial and the temporal two-point correlation functions of the condensate field itself. The decay of the temporal two-point correlator assumes a stretched-exponential form, providing further quantitative evidence for an effective KPZ description. Moreover, we confirm the observability of this nonequilibrium scaling for typical current experimental setups with exciton-polariton systems, if cavities with a reduced Q factor are used.

  19. Tunneling effects in a one-dimensional quantum walk

    E-print Network

    Mostafa Annabestani; Seyed Javad Akhtarshenas; Mohamad Reza Abolhassani

    2010-04-25

    In this article we investigate the effects of shifting position decoherence, arisen from the tunneling effect in the experimental realization of the quantum walk, on the one-dimensional discreet time quantum walk. We show that in the regime of this type of noise the quantum behavior of the walker does not fade, in contrary to the coin decoherence for which the walker undergos the quantum-to-classical transition even for weak noise. Particularly, we show that the quadratic dependency of the variance on the time and also the coin-position entanglement, i.e. two important quantum aspects of the coherent quantum walk, are preserved in the presence of tunneling decoherence. Furthermore, we present an explicit expression for the probability distribution of decoherent one-dimensional quantum walk in terms of the corresponding coherent probabilities, and show that this type of decoherence smooths the probability distribution.

  20. Excitonic condensation in spatially separated one-dimensional systems

    SciTech Connect

    Abergel, D. S. L.

    2015-05-25

    We show theoretically that excitons can form from spatially separated one-dimensional ground state populations of electrons and holes, and that the resulting excitons can form a quasicondensate. We describe a mean-field Bardeen-Cooper-Schrieffer theory in the low carrier density regime and then focus on the core-shell nanowire giving estimates of the size of the excitonic gap for InAs/GaSb wires and as a function of all the experimentally relevant parameters. We find that optimal conditions for pairing include small overlap of the electron and hole bands, large effective mass of the carriers, and low dielectric constant of the surrounding media. Therefore, one-dimensional systems provide an attractive platform for the experimental detection of excitonic quasicondensation in zero magnetic field.

  1. One-dimensional Hubbard-Luttinger model for carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Ishkhanyan, H. A.; Krainov, V. P.

    2015-06-01

    A Hubbard-Luttinger model is developed for qualitative description of one-dimensional motion of interacting Pi-conductivity-electrons in carbon single-wall nanotubes at low temperatures. The low-lying excitations in one-dimensional electron gas are described in terms of interacting bosons. The Bogolyubov transformation allows one to describe the system as an ensemble of non-interacting quasi-bosons. Operators of Fermi excitations and Green functions of fermions are introduced. The electric current is derived as a function of potential difference on the contact between a nanotube and a normal metal. Deviations from Ohm law produced by electron-electron short-range repulsion as well as by the transverse quantization in single-wall nanotubes are discussed. The results are compared with experimental data.

  2. Impurity Green's function of a one-dimensional Fermi gas

    NASA Astrophysics Data System (ADS)

    Gamayun, Oleksandr; Pronko, Andrei G.; Zvonarev, Mikhail B.

    2015-03-01

    We consider a one-dimensional gas of spin-1/2 fermions interacting through ?-function repulsive potential of an arbitrary strength. For the case of all fermions but one having spin up, we calculate time-dependent two-point correlation function of the spin-down fermion. This impurity Green's function is represented in the thermodynamic limit as an integral of Fredholm determinants of integrable linear integral operators.

  3. Effects of lasing in a one-dimensional quantum metamaterial

    NASA Astrophysics Data System (ADS)

    Asai, Hidehiro; Savel'ev, Sergey; Kawabata, Shiro; Zagoskin, Alexandre M.

    2015-04-01

    Electromagnetic pulse propagation in a quantum metamaterial, an artificial, globally quantum coherent optical medium, is numerically simulated. We show that a one-dimensional quantum metamaterial based on superconducting quantum bits, initialized in an easily reachable factorized excited state, demonstrates lasing in the microwave range, accompanied by the chaotization of qubit states and generation of higher harmonics. These effects may provide a tool for characterization and optimization of quantum metamaterial prototypes.

  4. Hidden Symmetry from Supersymmetry in One-Dimensional Quantum Mechanics

    E-print Network

    Alexander A. Andrianov; Andrey V. Sokolov

    2009-06-17

    When several inequivalent supercharges form a closed superalgebra in Quantum Mechanics it entails the appearance of hidden symmetries of a Super-Hamiltonian. We examine this problem in one-dimensional QM for the case of periodic potentials and potentials with finite number of bound states. After the survey of the results existing in the subject the algebraic and analytic properties of hidden-symmetry differential operators are rigorously elaborated in the Theorems and illuminated by several examples.

  5. Thermalization in a one-dimensional integrable system

    SciTech Connect

    Grisins, Pjotrs; Mazets, Igor E.

    2011-11-15

    We present numerical results demonstrating the possibility of thermalization of single-particle observables in a one-dimensional system, which is integrable in both the quantum and classical (mean-field) descriptions (a quasicondensate of ultracold, weakly interacting bosonic atoms are studied as a definite example). We find that certain initial conditions admit the relaxation of single-particle observables to the equilibrium state reasonably close to that corresponding to the Bose-Einstein thermal distribution of Bogoliubov quasiparticles.

  6. Cloud pumping in a one-dimensional photochemical model

    NASA Technical Reports Server (NTRS)

    Costen, Robert C.; Tennille, Geoffrey M.; Levine, Joel S.

    1988-01-01

    Cloud pumping data based on tropical maritime updraft statistics are incorporated in a one-dimensional steady-state eddy diffusive photochemical model of the troposphere. It is suggested that regions with weaker convection, such as the midlatitudes, may also experience substantial effects from cloud pumping. The direct effects of cloud pumping on CO were found to be more significant than implied by sensitivity studies. The (CH3)2S profile computed with cloud pumping agrees well with previous data.

  7. Effective Bragg conditions in a one-dimensional quasicrystal.

    PubMed

    Hsueh, W J; Chang, C H; Cheng, Y H; Wun, S J

    2012-11-19

    We present occurrence of the effective Bragg conditions with wide gapwidth and high reflectance in a Fibonacci superlattice, which is a typical one-dimensional quasicrystal. In the Fibonacci material, the number of effective Bragg conditions is two rather than one which appears in traditional periodic structures. Based on the effective Bragg conditions, this study proposes existence of omnidirectional, wideband and high reflectance in the quasiperiodic materials analogous to that in traditional materials. PMID:23187516

  8. On numerical modeling of one-dimensional geothermal histories

    USGS Publications Warehouse

    Haugerud, R.A.

    1989-01-01

    Numerical models of one-dimensional geothermal histories are one way of understanding the relations between tectonics and transient thermal structure in the crust. Such models can be powerful tools for interpreting geochronologic and thermobarometric data. A flexible program to calculate these models on a microcomputer is available and examples of its use are presented. Potential problems with this approach include the simplifying assumptions that are made, limitations of the numerical techniques, and the neglect of convective heat transfer. ?? 1989.

  9. Growth of one-dimensional single-crystalline hydroxyapatite nanorods

    NASA Astrophysics Data System (ADS)

    Ren, Fuzeng; Ding, Yonghui; Ge, Xiang; Lu, Xiong; Wang, Kefeng; Leng, Yang

    2012-06-01

    A facile, effective and template/surfactant-free hydrothermal route in the presence of sodium bicarbonate was developed to synthesize highly uniform single-crystalline hydroxyapatite (HA) nanorods with the lengths of several hundred nanometers and aspect ratio up to ˜20. One dimensional (1-D) growth and aspect ratio could be controlled by hydrothermal reaction time and temperature. The longitudinal axis, also the growth direction of the nanorods, is parallel to the [001] direction of HA hexagonal crystal structure.

  10. Gravitational anomalies and one dimensional behaviour of black holes

    E-print Network

    Bibhas Ranjan Majhi

    2015-11-25

    It has been pointed out by Bekenstein and Mayo that the behavior of the Black hole's entropy or information flow is similar to that through one-dimensional channel. Here I analyse the same issue with the use of gravitational anomalies. The rate of the entropy change ($\\dot{S}$) and the power ($P$) of the Hawking emission are calculated from the relevant components of the anomalous stress-tensor under the Unruh vacuum condition. I show that the dependence of $\\dot{S}$ on power is $\\dot{S}\\propto P^{1/2}$ which is identical to that for the information flow in one dimensional system. This is established by using the ($1+1$) dimensional gravitational anomalies first. Then the fact is further bolstered by considering the ($1+3$) dimensional gravitational anomalies. It is found that in the former case, the proportionality constant is exactly identical to one dimensional situation, known as Pendry's formula, while in later situation its value decreases.

  11. Gravitational anomalies and one dimensional behaviour of black holes

    E-print Network

    Majhi, Bibhas Ranjan

    2015-01-01

    It has been pointed out by Bekenstein and Mayo that the behavior of the Black hole's entropy or information flow is similar to that through one-dimensional channel. Here I analyse the same issue with the use of gravitational anomalies. The rate of the entropy change ($\\dot{S}$) and the power ($P$) of the Hawking emission are calculated from the relevant components of the anomalous stress-tensor under the Unruh vacuum condition. I show that the dependence of $\\dot{S}$ on power is $\\dot{S}\\propto P^{1/2}$ which is identical to that for the information flow in one dimensional system. This is established by using the ($1+1$) dimensional gravitational anomalies first. Then the fact is further bolstered by considering the ($1+3$) dimensional gravitational anomalies. It is found that in the former case, the proportionality constant is exactly identical to one dimensional situation, known as Pendry's formula, while in later situation its value decreases.

  12. One dimensional transient fluid model for fuel coolant interaction analysis

    SciTech Connect

    Chu, C.C.C.

    1986-01-01

    A hydrodynamic liquid drop fragmentation model for 10 < We < 10/sup 5/ was developed by using the Rayleigh Taylor instability with a drop deformation mechanism. This model is used to predict the transient drop breakup phases and obtain a theoretical correlation of the fragment size with time. This model is then incorporated into a one-dimensional transient fluid model to better characterize the fuel coolant mixing processes for fundamental understanding of fuel coolant interaction (FCI). This drop fragmentation model when compared to the previous drop breakup results in the gas/liquid system gave good agreement with experimental data. To demonstrate the capabilities of the one-dimensional transient fluid model, several sample problems were solved and compared to known analytic results or experimental data. Comparisons show that this hydrodynamic liquid drop fragmentation model was successfully incorporated into this one-dimensional transient fluid model. Furthermore, the intermediate-scale experiments and full-scale simulation of fuel jet/water mixing are investigated to more fundamentally understand the fuel coolant fragmentation and mixing behavior.

  13. Honeycomb-shaped coordination polymers based on the self-assembly of long flexible ligands and alkaline-earth ions

    NASA Astrophysics Data System (ADS)

    Lian, Chen; Liu, Liu; Guo, Xu; Long, Yinshuang; Jia, Shanshan; Li, Huanhuan; Yang, Lirong

    2016-01-01

    Two novel coordination polymers, namely, [Ca(NCP)2]? (I) and [Sr(NCP)2]? (II) were synthesized under hydrothermal conditions based on 2-(4-carboxyphenyl)imidazo(4,5-f)-(1,10)phenanthroline (HNCP) and characterized by elemental analysis, infrared spectrometry, X-ray powder diffraction and single crystal X-ray diffraction. Findings indicate that I and II are isomorphous and isostructural, containing the unit of M(NCP-)4 (M=Ca(II) and Sr(II)), based on which to assemble into three-dimensional (3D) porous 4-fold interpenetration honeycomb-shaped neutral coordination polymers (CPs). Between the adjacent lamellar structures in I and II, there exist ?-? interactions between the pyridine rings belonging to phenanthroline of NCP- which stabilize the frameworks. Both I and II display stronger fluorescence emissions as well as high thermal stability.

  14. Effects of isomorphous substitution of a coordination polymer on the properties and its application in electrochemical sensing

    SciTech Connect

    Zhou, Bo; Liang, Li-Mei; Yao, Jie

    2014-07-01

    This work concerns the isomorphous substitution of coordination polymers (CPs) and its effect on the optical and electrochemical properties. The application of CPs in electrochemical sensing was studied as well. Isomorphous coordination polymers, [Co{sub x}Zn{sub 1?x}tyr]{sub n} (tyr=L-tyrosine), where x (0–1) was controlled by the Co/Zn ratios of raw materials, were successfully synthesized via a hydrothermal method, as proved by XRD and EDS results. Their UV–vis DRS and fluorescence spectra change gradually along with the composition. Cyclic voltammograms of modified electrodes, [Co{sub x}Zn{sub 1?x}tyr]{sub n}/GCE, show that as more and more Zn replaced Co, the current signal decreases greatly and the potential shifts negatively. Much attention was paid to [Cotyr]{sub n} due to its highest sensitivity. Refreshable modified carbon paste electrode, [Cotyr]{sub n}-CPE, was used to determine nitrite, and showed pretty good performance as evidenced by chronoamperometry. The response was made very fast within mere 5 s. The linear detection range was from 5.00×10{sup ?5} to 3.45×10{sup ?3} M, with sensitivity of 263.4 mA mol{sup ?1} L cm{sup ?2}. The detection limit was found to be 2.00×10{sup ?5} M. The sensor also showed good antiinterference and reproducibility. - Graphical abstract: Evolution of the optical and electrochemical properties of isomorphic coordination polymers [Co{sub x}Zn{sub 1?x}tyr]{sub n} along with the changing of x was studied. The CP also showed perfect performance in the electrochemical determination of nitrite. - Highlights: • Isomorphous substitution of coordination polymers (CPs). • Substitution-caused evolution of optical and electrochemical properties of CPs. • Application of CPs in electrochemical sensing, an incipient area. • Perfect performance of CPs in electrochemical determination of nitrite.

  15. Cu{sup II} coordination polymers based on 5-methoxyisophthalate and flexible N-donor ligands: Structures and magnetic properties

    SciTech Connect

    Chang, Xin-Hong; Qin, Jian-Hua; Ma, Lu-Fang; Wang, Li-Ya

    2014-04-01

    Three Cu{sup II} coordination polymers, ([Cu{sub 2}(CH{sub 3}O-ip){sub 2}(bmib)]){sub n} (1), ([Cu{sub 2}(CH{sub 3}O-ip){sub 2}(bmib){sub 2}]){sub n} (2) and ([Cu(CH{sub 3}O-ip)(bbip)]?2H{sub 2}O){sub n} (3) (CH{sub 3}O-H{sub 2}ip is 5-methoxyisophthalic acid, bmib is 1,4-bis(2-methylimidazol-1-yl)butane and bbip is 1,3-bis(1H-benzimidazolyl)propane), have been synthesized by hydrothermal methods. Complexes 1–3 were structurally characterized by elemental analysis, infrared (IR) spectra and X-ray single-crystal diffraction. Complex 1 shows a 3D six-connected self-penetrating network based on paddlewheel secondary building units. Complex 2 has a 3-fold interpenetrating 3D diamond framework. Complex 3 possesses a 1D tube-like chain. Thermo-gravimetric and magnetic properties of 1–3 were also investigated. - Graphical abstract: Structures and magnetic properties of copper(II) coordination polymers constructed from 5-methoxyisophthalate linker and two flexible N-donor ancillary ligands. Three copper(II) coordination polymers with 5-methoxyisophthalate and two related flexible N-donor ancillary ligands have been synthesized and structurally characterized. Moreover, thermal behaviors and magnetic properties of these complexes have also been investigated. - Highlights: • Three Cu(II) coordination polymers were synthesized. • The conformations of N-donor ligands and pH value have an effect on the final structures. • The magnetic properties of 1–3 have been investigated.

  16. Synthesis, characterization and photoluminescence properties of two new europium(III) coordination polymers with 3D open framework

    NASA Astrophysics Data System (ADS)

    Zhang, Guoqi; Wang, Qian; Qian, Yan; Yang, Guoqiang; Shi Ma, Jin

    2006-08-01

    The 3D open framework coordination polymers, [Eu 2( fum) 3(H 2O) 4] n·3 nH 2O ( 1, fum=fumaric acid) and [Eu( pdc)(H pdc)] n ( 2, pdc=pyridine-2,5-dicarboxylic acid) have been synthesized via hydrothermal procedure. Their molecular structures were determined by single-crystal X-ray diffraction analysis. Polymer 1 adopts a 3D microporous structure filled with disordered free water molecules which interact by hydrogen bonds with terminal water bound to the metal centers. IR spectroscopy, TGA and powder X-ray diffraction analysis revealed that the remarkable dehydration-rehydration process of open-framework 1 is completely reversible. Polymer 2 forms a 3D framework composed of 2D grid-like inorganic subnetworks and pdc ligands as linkers. This solid is highly stable up to 405 °C. The solid-state photoluminescence measurements exhibited red light-emitting characteristic of two europium(III) coordination polymers. Moreover, the anhydrous products were found to be more strongly fluorescent and be of longer lifetime.

  17. Highly efficient stabilisation of meta-ethynylpyridine polymers with amide side chains in water by coordination of rare-earth metals.

    PubMed

    Makida, Hiroki; Abe, Hajime; Inouye, Masahiko

    2015-02-14

    An amphiphilic meta-ethynylpyridine polymer with chiral amide side chains was developed. The polymer was prepared by sequential Sonogashira reactions, and the product was soluble in polar and apolar solvents. The additive effects of metal salts on the polymer were examined in water and aqueous EtOH on the basis of UV-vis and CD spectra. The enhancement of the positive Cotton effect and hypochromism around 360 nm occurred by the addition of various metal salts, indicating the coordination of the cations to the amide side chains of the polymer to stabilise the helical structure. Among them, rare-earth metal salts, especially Sc(OTf)3 showed more efficient additive effects probably because of its strong coordination ability even in water. Positive cooperativity was observed for the coordination of Sc(OTf)3 to the polymer in aqueous EtOH. PMID:25473810

  18. Series of mixed uranyl-lanthanide (Ce, Nd) organic coordination polymers with aromatic polycarboxylates linkers.

    PubMed

    Mihalcea, Ionut; Volkringer, Christophe; Henry, Natacha; Loiseau, Thierry

    2012-09-17

    Three series of mixed uranyl-lanthanide (Ce or Nd) carboxylate coordination polymers have been successfully synthesized by means of a hydrothermal route using either conventional or microwave heating methods. These compounds have been prepared from mixtures of uranyl nitrate, lanthanide nitrate together with phthalic acid (1,2), pyromellitic acid (3,4), or mellitic acid (5,6) in aqueous solution. The X-ray diffraction (XRD) single-crystal revealed that the phthalate complex (UO(2))(4)O(2)Ln(H(2)O)(7)(1,2-bdc)(4)·NH(4)·xH(2)O (Ln = Ce(1), Nd(2); x = 1 for 1, x = 0 for 2), is based on the connection of tetranuclear uranyl-centered building blocks linked to discrete monomeric units LnO(2)(H(2)O)(7) via the organic species to generate infinite chains, intercalated by free ammonium cations. The pyromellitate phase (UO(2))(3)Ln(2)(H(2)O)(12)(btec)(3)·5H(2)O (Ce(3), Nd(4)) contains layers of monomeric uranyl-centered hexagonal and pentagonal bipyramids linked via the carboxylate arms of the organic molecules. The three-dimensionality of the structure is ensured by the connection of remaining free carboxylate groups with isolated monomeric units LnO(2)(H(2)O)(7). The network of the third series (UO(2))(2)(OH)Ln(H(2)O)(7)(mel)·5H(2)O (Ce(5), Nd(6)) is built up from dinuclear uranyl units forming layers through connection with the mellitate ligands, which are further linked to each other through discrete monomers LnO(3)(H(2)O)(6). The thermal decomposition of the various coordination complexes led to the formation of mixed uranium-lanthanide oxide, with the fluorite-type structure at 1500 °C (for 1, 2) or 1400 °C for 3-6. Expected U/Ln ratio from the crystal structures were observed for compounds 1-6. PMID:22931214

  19. Validity of one-dimensional QED for a system with spatial symmetry

    NASA Astrophysics Data System (ADS)

    Lv, Q. Z.; Christensen, N. D.; Su, Q.; Grobe, R.

    2015-11-01

    We examine the accuracy of an intrinsically one-dimensional (1D) quantum electrodynamics to predict accurately the forces and charges of a three-dimensional (3D) system that has a high degree of symmetry and therefore depends effectively only on a single coordinate. As a test case we analyze two charged capacitor plates that are infinitely extended along two coordinate directions. Using the lowest-order fine-structure correction to the photon propagator we compute the vacuum's induced charge polarization density and show that the force between the charged plates is increased. Although a one-dimensional theory cannot take the transverse character of the virtual (force-mediating) photons into account, nevertheless it predicts, in lowest order of the fine-structure constant, the Coulomb force law between the plates correctly. However, the quantum correction to the classical result is slightly different between the 1D and 3D theories with the polarization charge density induced from the vacuum underestimated by the 1D approach.

  20. Coordination polymer submicrospheres: fast microwave synthesis and their conversion under different atmospheres.

    PubMed

    Zhong, Shengliang; Jing, Hongyu; Li, Yuan; Yin, Shungao; Zeng, Chenghui; Wang, Lei

    2014-08-18

    Rare earth (RE) based coordination polymer (CP) submicrospheres have been prepared from pyridine-2,5-dicarboxylic acid and RE(NO3)3 via a facile microwave heating method in 5 min, with N,N-dimethylformamide (DMF) as solvent. The submicrospheres have diameters of 100-400 nm. Furthermore, the surface of the microspheres is smooth and the microspheres are solid. Several CP submicrospheres (RE = La, Gd, Y) were selected and calcined under different atmospheres (including air, N2, and NH3). After calcination in air at 550 °C for 4 h, rare earth oxide (RE2O3) submicrospheres were obtained. On calcination under an N2 atmosphere, LaN/La2O3/C composite spheres were obtained for La-based CPs. For Gd(Y)-based CPs, Gd2O3(Y2O3)/C composite spheres were obtained. Porous carbon submicrospheres were obtained after the removal of RE2O3 and REN from the composite spheres. Interestingly, under an NH3 atmosphere, La2O2CN2 submicrospheres were produced from the La-based CPs. In addition, the Gd-based and Y-based CPs submicrospheres gave Gd2O3/GdN/C and Y2O3/C submicrospheres, respectively. As examples of their potential applications, their upconversion properties and electrochemical properties of the as-prepared products were investigated. This facile microwave synthesis method may offer an attractive approach for the preparation of other RE-CP micro-/nanostructures, and many interesting materials may be derived. PMID:25083590

  1. One-Dimensional Scanning Approach to Shock Sensing

    NASA Technical Reports Server (NTRS)

    Tokars, Roger; Adamovsky, Girgory; Floyd, Bertram

    2009-01-01

    Measurement tools for high speed air flow are sought both in industry and academia. Particular interest is shown in air flows that exhibit aerodynamic shocks. Shocks are accompanied by sudden changes in density, pressure, and temperature. Optical detection and characterization of such shocks can be difficult because the medium is normally transparent air. A variety of techniques to analyze these flows are available, but they often require large windows and optical components as in the case of Schlieren measurements and/or large operating powers which precludes their use for in-flight monitoring and applications. The one-dimensional scanning approach in this work is a compact low power technique that can be used to non-intrusively detect shocks. The shock is detected by analyzing the optical pattern generated by a small diameter laser beam as it passes through the shock. The optical properties of a shock result in diffraction and spreading of the beam as well as interference fringes. To investigate the feasibility of this technique a shock is simulated by a 426 m diameter optical fiber. Analysis of results revealed a direct correlation between the optical fiber or shock location and the beam s diffraction pattern. A plot of the width of the diffraction pattern vs. optical fiber location reveals that the width of the diffraction pattern was maximized when the laser beam is directed at the center of the optical fiber. This work indicates that the one-dimensional scanning approach may be able to determine the location of an actual shock. Near and far field effects associated with a small diameter laser beam striking an optical fiber used as a simulated shock are investigated allowing a proper one-dimensional scanning beam technique.

  2. Aromatic carboxylate effect on dimensionality of three bis(benzimidazole)-based cobalt(II) coordination polymers: Syntheses, structures and properties

    NASA Astrophysics Data System (ADS)

    Zhang, Ju-Wen; Gong, Chun-Hua; Hou, Li-Li; Tian, Ai-Xiang; Wang, Xiu-Li

    2013-09-01

    Three new metal-organic coordination polymers [Co(4-bbc)2(bbbm)] (1), [Co(3,5-pdc)(bbbm)]·2H2O (2) and [Co(1,4-ndc)(bbbm)] (3) (4-Hbbc=4-bromobenzoic acid, 3,5-H2pdc=3,5-pyridinedicarboxylic acid, 1,4-H2ndc=1,4-naphthalenedicarboxylic acid and bbbm=1,1-(1,4-butanediyl)bis-1H-benzimidazole) were hydrothermally synthesized and structurally characterized. Polymer 1 is a 1D chain formed by the bbbm ligands and CoII ions. Polymer 2 exhibits a 2D network with a (3·4·5)(32·4·5·62·74) topology. Polymer 3 possesses a 3D three-fold interpenetrating framework. The versatile structures of title polymers indicate that the aromatic carboxylates have an important influence on the dimensionality of 1-3. Moreover, the thermal stability, electrochemical and luminescent properties of 1-3 were investigated.

  3. Programmers manual for a one-dimensional Lagrangian transport model

    USGS Publications Warehouse

    Schoellhamer, D.H.; Jobson, H.E.

    1986-01-01

    A one-dimensional Lagrangian transport model for simulating water-quality constituents such as temperature, dissolved oxygen , and suspended sediment in rivers is presented in this Programmers Manual. Lagrangian transport modeling techniques, the model 's subroutines, and the user-written decay-coefficient subroutine are discussed in detail. Appendices list the program codes. The Programmers Manual is intended for the model user who needs to modify code either to adapt the model to a particular need or to use reaction kinetics not provided with the model. (Author 's abstract)

  4. On a Phase Separation Point for One - Dimensional Models

    E-print Network

    N. N. Ganikhodjaev; U. A. Rozikov

    2007-08-09

    In the paper a one-dimensional model with nearest - neighbor interactions $I_n, n\\in \\Z$ and spin values $\\pm 1$ is considered. It is known that under some conditions on parameters $I_n$ the phase transition occurs for the model. We define a notion of "phase separation" point between two phases. We prove that the expectation value of the point is zero and its the mean square fluctuation is bounded by a constant $C(\\beta)$ which tends to 1/4 if $\\beta\\to\\infty$. Here $\\beta=\\frac{1}{T}$, $ T>0$-temperature.

  5. Parallel solution of sparse one-dimensional dynamic programming problems

    NASA Technical Reports Server (NTRS)

    Nicol, David M.

    1989-01-01

    Parallel computation offers the potential for quickly solving large computational problems. However, it is often a non-trivial task to effectively use parallel computers. Solution methods must sometimes be reformulated to exploit parallelism; the reformulations are often more complex than their slower serial counterparts. We illustrate these points by studying the parallelization of sparse one-dimensional dynamic programming problems, those which do not obviously admit substantial parallelization. We propose a new method for parallelizing such problems, develop analytic models which help us to identify problems which parallelize well, and compare the performance of our algorithm with existing algorithms on a multiprocessor.

  6. Dynamical Structure Factors of quasi-one-dimensional antiferromagnets

    NASA Astrophysics Data System (ADS)

    Hagemans, Rob; Caux, Jean-Sébastien; Maillet, Jean Michel

    2007-03-01

    For a long time it has been impossible to accurately calculate the dynamical structure factors (spin-spin correlators as a function of momentum and energy) of quasi-one-dimensional antiferromagnets. For integrable Heisenberg chains, the recently developed ABACUS method (a first-principles computational approach based on the Bethe Ansatz) now yields highly accurate (over 99% of the sum rule) results for the DSF for finite chains, allowing for a very precise description of neutron-scattering data over the full momentum and energy range. We show remarkable agreement between results obtained with ABACUS and experiment.

  7. Numerical computations on one-dimensional inverse scattering problems

    NASA Technical Reports Server (NTRS)

    Dunn, M. H.; Hariharan, S. I.

    1983-01-01

    An approximate method to determine the index of refraction of a dielectric obstacle is presented. For simplicity one dimensional models of electromagnetic scattering are treated. The governing equations yield a second order boundary value problem, in which the index of refraction appears as a functional parameter. The availability of reflection coefficients yield two additional boundary conditions. The index of refraction by a k-th order spline which can be written as a linear combination of B-splines is approximated. For N distinct reflection coefficients, the resulting N boundary value problems yield a system of N nonlinear equations in N unknowns which are the coefficients of the B-splines.

  8. Phaseless inverse scattering in the one-dimensional case

    E-print Network

    Roman Novikov

    2015-03-07

    We consider the one-dimensional Schr\\"odinger equation with a potential satisfying the standard assumptions of the inverse scattering theory and supported on the half-line $x\\ge 0$. For this equation at fixed positive energy we give explicit formulas for finding the full complex valued reflection coefficient to the left from appropriate phaseless scattering data measured on the left, i.e. for $xinverse scattering results we obtain global uniqueness and reconstruction results for phaseless inverse scattering in dimension $d=1$.

  9. Numerical computations on one-dimensional inverse scattering problems

    NASA Technical Reports Server (NTRS)

    Dunn, M. H.; Hariharan, S. I.

    1984-01-01

    An approximate method to determine the index of refraction of a dielectric obstacle is presented. For simplicity one dimensional models of electromagnetic scattering are treated. The governing equations yield a second order boundary value problem, in which the index of refraction appears as a functional parameter. The availability of reflection coefficients yield two additional boundary conditions. The index of refraction by a k-th order spline which can be written as a linear combination of B-splines is approximated. For N distinct reflection coefficients, the resulting N boundary value problems yield a system of N nonlinear equations in N unknowns which are the coefficients of the B-splines.

  10. One-dimensional modeling of secondary clarifiers for wastewater treatment

    SciTech Connect

    Watts, R.W.; Svoronos, S.A.; Koopman, B.

    1996-12-31

    A one-dimensional model of activated sludge secondary clarifiers with a variable dispersion coefficient dependent on concentration and feed velocity was developed. Data collected from a full-scale clarifier at the Kanapaha Water Reclamation Facility in Gainesville, FL were used to evaluate this model. Data from three experimental periods demonstrated the ability of the model to predict steady state sludge blanket levels as well as clarifier failure. The variable dispersion coefficient model outperformed other well-known models in predicting clarifier overloading. 15 refs., 1 fig., 3 tabs.

  11. Quantum quenches and thermalization in one-dimensional systems

    NASA Astrophysics Data System (ADS)

    Rigol, Marcos

    2010-03-01

    We use quantum quenches to study the dynamics and thermalization of hardcore bosons and fermions in finite one-dimensional lattices. We perform exact diagonalizations and find that, far away from integrability, few-body observables thermalize. We then study the breakdown of thermalization as one approaches an integrable point. This is found to be a smooth process in which the predictions of standard statistical mechanics continuously worsen as the system moves toward integrability. We establish a direct connection between the presence or absence of thermalization and the validity or failure of the eigenstate thermalization hypothesis, respectively.ReferencesM. Rigol, Phys. Rev. Lett. 103, 100403 (2009); Phys. Rev. A 80, 053607 (2009).

  12. Quantum mechanics of graphene with a one-dimensional potential

    SciTech Connect

    Miserev, D. S.; Entin, M. V.

    2012-10-15

    Electron states in graphene with a one-dimensional potential have been studied. An approximate solution has been obtained for a small angle between vectors of the incident electron momentum and potential gradient. Exactly solvable problems with a potential of the smoothened step type U(x) Utanh(x/a) and a potential with a singularity U(x) = -U/(|x| + d) are considered. The transmission/reflection coefficients and phases for various potential barriers are determined. A quasi-classical solution is obtained.

  13. Breakdown of Thermalization in Finite One-Dimensional Systems

    SciTech Connect

    Rigol, Marcos

    2009-09-04

    We use quantum quenches to study the dynamics and thermalization of hard core bosons in finite one-dimensional lattices. We perform exact diagonalizations and find that, far away from integrability, few-body observables thermalize. We then study the breakdown of thermalization as one approaches an integrable point. This is found to be a smooth process in which the predictions of standard statistical mechanics continuously worsen as the system moves toward integrability. We establish a direct connection between the presence or absence of thermalization and the validity or failure of the eigenstate thermalization hypothesis, respectively.

  14. Tunable dark modes in one-dimensional "diatomic" dielectric gratings.

    PubMed

    Zeng, Bo; Majumdar, Arka; Wang, Feng

    2015-05-18

    Recently researchers have demonstrated ultra high quality factor (Q) resonances in one-dimensional (1D) dielectric gratings. Here we theoretically investigate a new class of subwavelength 1D gratings, namely "diatomic" gratings with two nonequivalent subcells in one period, and utilize their intrinsic dark modes to achieve robust ultra high Q resonances. Such "diatomic" gratings provide extra design flexibility, and enable high Q resonators using thinner geometry with smaller filling factors compared to conventional designs like the high contrast gratings (HCGs). More importantly, we show that these high Q resonances can be efficiently tuned in situ, making the design appealing in various applications including optical sensing, filtering and displays. PMID:26074503

  15. Computer model of one-dimensional equilibrium controlled sorption processes

    USGS Publications Warehouse

    Grove, D.B.; Stollenwerk, K.G.

    1984-01-01

    A numerical solution to the one-dimensional solute-transport equation with equilibrium-controlled sorption and a first-order irreversible-rate reaction is presented. The computer code is written in FORTRAN language, with a variety of options for input and output for user ease. Sorption reactions include Langmuir, Freundlich, and ion-exchange, with or without equal valance. General equations describing transport and reaction processes are solved by finite-difference methods, with nonlinearities accounted for by iteration. Complete documentation of the code, with examples, is included. (USGS)

  16. Exciton recombination in one-dimensional organic Mott insulators

    NASA Astrophysics Data System (ADS)

    Lenar?i?, Zala; Eckstein, Martin; Prelovšek, Peter

    2015-11-01

    We present a theory for the recombination of (charged) holons and doublons in one-dimensional organic Mott insulators, which is responsible for the decay of the photoexcited state. Due to the charge-spin separation, the dominant mechanism for recombination at low density of charges involves a multiphonon emission. We show that a reasonable coupling to phonons is sufficient to explain the fast recombination observed by pump-probe experiments in ET -F2TCNQ , whereby we can also account for the measured pressure dependence of the recombination rate.

  17. Bioheat transfer problem for one-dimensional spherical biological tissues.

    PubMed

    Kengne, Emmanuel; Lakhssassi, Ahmed

    2015-11-01

    Based on the Pennes bioheat transfer equation with constant blood perfusion, we set up a simplified one-dimensional bioheat transfer model of the spherical living biological tissues for application in bioheat transfer problems. Using the method of separation of variables, we present in a simple way the analytical solution of the problem. The obtained exact solution is used to investigate the effects of tissue properties, the cooling medium temperature, and the point-heating on the temperature distribution in living bodies. The obtained analytical solution can be useful for investigating thermal behavior research of biological system, thermal parameter measurements, temperature field reconstruction and clinical treatment. PMID:26327484

  18. Wavelet Analysis of One-Dimensional Cosmological Density Fluctuations

    E-print Network

    Yoshi Fujiwara; Jiro Soda

    1995-09-21

    Wavelet analysis is proposed as a new tool for studying the large-scale structure formation of the universe. To reveal its usefulness, the wavelet decomposition of one-dimensional cosmological density fluctuations is performed. In contrast with the Fourier analysis, the wavelet analysis has advantage of its ability to keep the information for location of local density peaks in addition to that for their scales. The wavelet decomposition of evolving density fluctuations with various initial conditions is examined. By comparing the wavelet analysis with the usual Fourier analysis, we conclude that the wavelet analysis is promising as the data analysis method for the Sloan Digital Sky Survey and COBE.

  19. Evaluation of one dimensional analytical models for vegetation canopies

    NASA Technical Reports Server (NTRS)

    Goel, Narendra S.; Kuusk, Andres

    1992-01-01

    The SAIL model for one-dimensional homogeneous vegetation canopies has been modified to include the specular reflectance and hot spot effects. This modified model and the Nilson-Kuusk model are evaluated by comparing the reflectances given by them against those given by a radiosity-based computer model, Diana, for a set of canopies, characterized by different leaf area index (LAI) and leaf angle distribution (LAD). It is shown that for homogeneous canopies, the analytical models are generally quite accurate in the visible region, but not in the infrared region. For architecturally realistic heterogeneous canopies of the type found in nature, these models fall short. These shortcomings are quantified.

  20. Homochiral 3D coordination polymer with unprecedented three-directional helical topology from achiral precursor: synthesis, crystal structure, and luminescence properties of uranyl succinate metal-organic framework.

    PubMed

    Wang, Juan; Wei, Zhen; Guo, Fengwan; Li, Chenyang; Zhu, Pengfei; Zhu, Wenhua

    2015-08-21

    A luminescent homochiral uranyl succinate coordination polymer with unprecedented three-directional helices was synthesized hydrothermally via spontaneous symmetry breaking, and fully characterized. Its homochirality has been confirmed by singe crystal X-ray diffraction and solid state circular dichroism (CD) spectra. The polymer exhibited a Stokes shift greater than 180 nm. PMID:26167889

  1. A copper(I) coordination polymer incorporation the corrosion inhibitor 1H-benzotriazole: poly[?3-benzotriazolato-?(3)N(1):N(2):N(3)-copper(I)].

    PubMed

    Liu, Jian-Jun; Li, Zuo-Yin; Yuan, Xiong; Wang, Yao; Huang, Chang-Cang

    2014-06-01

    The title complex, [Cu(C6H4N3)]n, was synthesized by the reaction of cupric nitrate, 1H-benzotriazole (BTAH) and aqueous ammonia under hydrothermal conditions. The asymmetric unit contains three crystallographically independent Cu(I) cations and two 1H-benzotriazolate ligands. Two of the Cu(I) cations, one with a linear two-coordinated geometry and one with a four-coordinated tetrahedral geometry, are located on sites with crystallographically imposed twofold symmetry. The third Cu(I) cation, with a planar three-coordinated geometry, is on a general position. Two Cu(I) cations are doubly bridged by two BTA(-) ligands to afford a noncentrosymmetric planar [Cu2(BTA)2] subunit, and two [Cu2(BTA)2] subunits are arranged in an antiparallel manner to form a centrosymmetric [Cu2(BTA)2]2 secondary building unit (SBU). The SBUs are connected in a crosswise manner via the sharing of four-coordinated Cu(I) cations, Cu-N bonding and bridging by two-coordinate Cu(I) cations, resulting in a one-dimensional chain along the c axis. These one-dimensional chains are further linked by C-H···? and weak van der Waals interactions to form a three-dimensional supramolecular architecture. PMID:24898965

  2. Coordination Polymer Flexibility Leads to Polymorphism and Enables a Crystalline Solid–Vapour Reaction: A Multi-technique Mechanistic Study

    PubMed Central

    Vitórica-Yrezábal, Iñigo J; Libri, Stefano; Loader, Jason R; Mínguez Espallargas, Guillermo; Hippler, Michael; Fletcher, Ashleigh J; Thompson, Stephen P; Warren, John E; Musumeci, Daniele; Ward, Michael D; Brammer, Lee

    2015-01-01

    Despite an absence of conventional porosity, the 1D coordination polymer [Ag4(O2C(CF2)2CF3)4(TMP)3] (1; TMP=tetramethylpyrazine) can absorb small alcohols from the vapour phase, which insert into Ag–O bonds to yield coordination polymers [Ag4(O2C(CF2)2CF3)4(TMP)3(ROH)2] (1-ROH; R=Me, Et, iPr). The reactions are reversible single-crystal-to-single-crystal transformations. Vapour-solid equilibria have been examined by gas-phase IR spectroscopy (K=5.68(9)×10?5 (MeOH), 9.5(3)×10?6 (EtOH), 6.14(5)×10?5 (iPrOH) at 295 K, 1 bar). Thermal analyses (TGA, DSC) have enabled quantitative comparison of two-step reactions 1-ROH?1?2, in which 2 is the 2D coordination polymer [Ag4(O2C(CF2)2CF3)4(TMP)2] formed by loss of TMP ligands exclusively from singly-bridging sites. Four polymorphic forms of 1 (1-ALT, 1-AHT, 1-BLT and 1-BHT; HT=high temperature, LT=low temperature) have been identified crystallographically. In situ powder X-ray diffraction (PXRD) studies of the 1-ROH?1?2 transformations indicate the role of the HT polymorphs in these reactions. The structural relationship between polymorphs, involving changes in conformation of perfluoroalkyl chains and a change in orientation of entire polymers (A versus B forms), suggests a mechanism for the observed reactions and a pathway for guest transport within the fluorous layers. Consistent with this pathway, optical microscopy and AFM studies on single crystals of 1-MeOH/1-AHT show that cracks parallel to the layers of interdigitated perfluoroalkyl chains develop during the MeOH release/uptake process. PMID:25962844

  3. Coordination polymer flexibility leads to polymorphism and enables a crystalline solid-vapour reaction: a multi-technique mechanistic study.

    PubMed

    Vitórica-Yrezábal, Iñigo J; Libri, Stefano; Loader, Jason R; Mínguez Espallargas, Guillermo; Hippler, Michael; Fletcher, Ashleigh J; Thompson, Stephen P; Warren, John E; Musumeci, Daniele; Ward, Michael D; Brammer, Lee

    2015-06-01

    Despite an absence of conventional porosity, the 1D coordination polymer [Ag4 (O2 C(CF2 )2 CF3 )4 (TMP)3 ] (1; TMP=tetramethylpyrazine) can absorb small alcohols from the vapour phase, which insert into Ag?O bonds to yield coordination polymers [Ag4 (O2 C(CF2 )2 CF3 )4 (TMP)3 (ROH)2 ] (1-ROH; R=Me, Et, iPr). The reactions are reversible single-crystal-to-single-crystal transformations. Vapour-solid equilibria have been examined by gas-phase IR spectroscopy (K=5.68(9)×10(-5) (MeOH), 9.5(3)×10(-6) (EtOH), 6.14(5)×10(-5) (iPrOH) at 295?K, 1?bar). Thermal analyses (TGA, DSC) have enabled quantitative comparison of two-step reactions 1-ROH?1?2, in which 2 is the 2D coordination polymer [Ag4 (O2 C(CF2 )2 CF3 )4 (TMP)2 ] formed by loss of TMP ligands exclusively from singly-bridging sites. Four polymorphic forms of 1 (1-A(LT) , 1-A(HT) , 1-B(LT) and 1-B(HT) ; HT=high temperature, LT=low temperature) have been identified crystallographically. In situ powder X-ray diffraction (PXRD) studies of the 1-ROH?1?2 transformations indicate the role of the HT polymorphs in these reactions. The structural relationship between polymorphs, involving changes in conformation of perfluoroalkyl chains and a change in orientation of entire polymers (A versus B forms), suggests a mechanism for the observed reactions and a pathway for guest transport within the fluorous layers. Consistent with this pathway, optical microscopy and AFM studies on single crystals of 1-MeOH/1-A(HT) show that cracks parallel to the layers of interdigitated perfluoroalkyl chains develop during the MeOH release/uptake process. PMID:25962844

  4. Catalyst-site-controlled coordination polymerization of polar vinyl monomers to highly syndiotactic polymers.

    PubMed

    Zhang, Yuetao; Ning, Yalan; Caporaso, Lucia; Cavallo, Luigi; Chen, Eugene Y-X

    2010-03-01

    This contribution reports a combined synthetic, kinetic, mechanistic, and theoretical/computational study of the recently discovered catalyst-site-controlled coordination polymerization of polar vinyl monomers [such as methyl methacrylate (MMA) and N,N-dimethylacrylamide (DMAA)] into highly syndiotactic polymers. Among the 12 C(s)-ligated ansa-cyclopentadienyl (Cp)-R(2)E(C,Si)-fluorenyl (Flu) group 4 metallocene catalyst systems examined-which varied in metal center, anion structure, bridging atom and substituents, and ligand substitution pattern-cationic ansa-metallocene ester enolate catalyst 6(+)[B(C(6)F(5))(4)](-), derived from the activation of the precatalyst [Ph(2)C(Cp)(2,7-(t)Bu(2)-Flu)]Zr[OC(O(i)Pr)=CMe(2)](2) with [Ph(3)C][B(C(6)F(5))(4)], stood out as the best catalyst in all aspects of the MMA polymerization at room temperature, including the highest activity (1554 h(-1) TOF), efficiency (98% I*), syndiotacticity (94% rr), and control (predicted number-average molecular weight and 1.14 molecular weight distribution). Kinetic and mechanistic results are consistent with a catalyst-site-controlled, monometallic coordination-addition mechanism, involving fast intramolecular addition within the catalyst-monomer complex leading to the resting eight-membered ester enolate chelate, followed by the rate-limiting ring-opening of the chelate to regenerate the active species. This work has also uncovered several unique features of this polymerization system that are in marked contrast to the propylene polymerization by analogous C(s)-ligated cationic alkyl catalysts: a constant syndiotacticity of PMMA produced over a wide polymerization temperature range (i.e., from 0 degrees C, 94% rr to 25 degrees C, 94% rr to 50 degrees C, 93% rr); insensitivity of its high activity, degree of control, and stereoselectivity to solvent polarity and structure of weakly coordinating anions; and deviation from a pure site-control mechanism at high [MMA]/[catalyst] ratios. Computational results provide theoretical support for the proposed monomer-assisted, catalyst-site epimerization, after an enantiofacial mistake, to a thermodynamically more stable resting state, which accounts for the observed higher than expected [mr] contents based on a pure site-controlled mechanism. DFT calculations rationalize why the Ph(2)C< bridged catalyst 6 exhibits higher stereoselectivity than other catalysts with the Me(2)C< or Me(2)Si< bridge: the bridge rigidity pushes the eta(3)-bound Flu ligand closer to the growing chain and the monomer, thereby increasing DeltaE(stereo) between the competing transition states for the addition of a monomer molecule to the opposite (correct and wrong) enantiofaces of the enolate growing chain. The relative polymerization activity of this catalyst series is shown to correlate with the relative energetics of the back-biting of the penultimate unit and ion-pair formation. PMID:20121281

  5. Spectral-edge mode in interacting one-dimensional systems

    NASA Astrophysics Data System (ADS)

    Tsyplyatyev, O.; Schofield, A. J.

    2014-07-01

    A continuum of excitations in interacting one-dimensional systems is bounded from below by a spectral edge that marks the lowest possible excitation energy for a given momentum. We analyze short-range interactions between Fermi particles and between Bose particles (with and without spin) using Bethe-ansatz techniques and find that the dispersions of the corresponding spectral edge modes are close to a parabola in all cases. Based on this emergent phenomenon we propose an empirical model of a free, nonrelativistic particle with an effective mass identified at low energies as the bare electron mass renormalized by the dimensionless Luttinger parameter K (or K? for particles with spin). The relevance of the Luttinger parameters beyond the low-energy limit provides a more robust method for extracting them experimentally using a much wider range of data from the bottom of the one-dimensional band to the Fermi energy. The empirical model of the spectral edge mode complements the mobile impurity model to give a description of the excitations in proximity of the edge at arbitrary momenta in terms of only the low-energy parameters and the bare electron mass. Within such a framework, for example, exponents of the spectral function are expressed explicitly in terms of only a few Luttinger parameters.

  6. Flexible coordination polymers composed of luminescent ruthenium(II) metalloligands: importance of the position of the coordination site in metalloligands.

    PubMed

    Kobayashi, Atsushi; Ohba, Tadashi; Saitoh, Erika; Suzuki, Yui; Noro, Shin-ichiro; Chang, Ho-Chol; Kato, Masako

    2014-03-17

    Coordination polymerization reactions between ruthenium(II) metalloligands [Ru(n,n'-dcbpy)](4-) ([nRu]; n = 4, 5; n,n'-dcbpy = n,n'-dicarboxy-2,2'-bipyridine) and several divalent metal salts in basic aqueous solutions afforded porous luminescent complexes formulated as [Mg(H2O)6]{[Mg(H2O)3][4Ru]·4H2O} (Mg2[4Ru]·13H2O), [Mg2(H2O)9][5Ru]·10H2O (Mg2[5Ru]·19H2O), {[Sr4(H2O)9][4Ru]2·9H2O} (Sr2[4Ru]·9H2O)2, {[Sr2(H2O)8][5Ru]·6H2O} (Sr2[5Ru]·14H2O), and {[Cd2(H2O)2][5Ru]·10H2O} (Cd2[5Ru]·12H2O). Single-crystal X-ray structural analyses revealed that the divalent metal ions were commonly coordinated by the carboxyl groups of the [nRu] metalloligand, forming porous frameworks with a void fraction varying from 11.4% Mg2[4Ru]·13H2O to 43.9% Cd2[5Ru]·12H2O. M2[4Ru]·nH2O showed a reversible structural transition accompanied by water and methanol vapor adsorption/desorption, while the porous structures of M2[5Ru]·nH2O were irreversibly collapsed by the removal of crystal water. The triplet metal-to-ligand charge-transfer emission energies of M2[4Ru]·nH2O were lower than those of [4Ru] in aqueous solution, whereas those of M2[5Ru]·nH2O were close to those of [5Ru] in aqueous solution. These results suggested that the position of the coordination site in the metalloligand played an important role not only on the structure of the porous framework but also on the structural flexibility involving the guest adsorption/desorption properties. PMID:24558962

  7. One-dimensional non-stationary convection model

    NASA Astrophysics Data System (ADS)

    Sadokov, V. P.; Vasilevsky, K. D.

    2012-04-01

    One-dimensional convection model is widely used in large-scale atmospheric models for the description of the convective clouds and calculating precipitation. Such models are stationary and can not describe the dynamics of the convection. There are widely used the non-stationary version of the one-dimensional models that are remaining within the framework of the simple versions. Evaluation of the convection processes in these models differs from the stationary version. If we consider the results of the stationary version as an initial condition for the non-stationary model, then in the process of solving the non-stationary task it will be the development of convection and establishing of the convective. In the present paper the equation processes for the vertical velocity are considered. That contains the time derivative. It is solved by the finite-difference scheme for a variety of levels k. The number of the levels k is determined by the spline approximation of the input data. As a result we have a quadratic equation for the vertical velocity w, taking into account the effects of entrainment, detrainment and release of condensation heat. If the vertical velocity in the calculation is positive, we assume the formation of the cloud elements. Based on the equations for the specific humidity q, water content ? and the statistical stability s, and introduce to them the time derivatives we obtain the equations system for the one-dimensional non-stationary cloud model, that take into account the processes occurring inside the cloud and in the surrounding area. Also here is presented an approach for the calculation of the precipitation. Many experiments using the model were performed to optimize the input parameters, empirical coefficients and calculated algorithm. The calculations showed that all model parameters are changing over time and finally the development process is stabilized. This is due to the surrounding state of the atmosphere that does not changed in these calculations. Value of the time steps for the integration in the cloud and the time steps of changing the environment parameters must be conformed: the period of convection is less than the step of change in the external environment. In our case we choose a step in non-stationary cloud model up to 10 seconds. The model is convenient to use because minimum of the input data is required: the geopotential, pressure, temperature and humidity. At the output the model can provide quick calculations and fairly realistic values of the vertical velocity, precipitation, and the various parameters of the clouds. The presented algorithm can be adapted to large-scale hydrodynamical models of the atmosphere.

  8. Polymer complexes.. XXXX. Supramolecular assembly on coordination models of mixed-valence-ligand poly[1-acrylamido-2-(2-pyridyl)ethane] complexes

    NASA Astrophysics Data System (ADS)

    El-Sonbati, A. Z.; El-Bindary, A. A.; Diab, M. A.

    2003-02-01

    The build-up of polymer metallic supramolecules based on homopolymer (1-acrylamido-2-(2-pyridyl)ethane (AEPH)) and ruthenium, rhodium, palladium as well as platinum complexes has been pursued with great interest. The homopolymer shows three types of coordination behaviour. In the mixed valence paramagnetic trinuclear polymer complexes [( 11)+( 12)] in the paper and in mononuclear polymer complexes ( 1)-( 5) it acts as a neutral bidentate ligand coordinating through the N-pyridine and NH-imino atoms, while in the mixed ligand diamagnetic poly-chelates, which are obtained from the reaction of AEPH with PdX 2 and KPtCl 4 in the presence of N-heterocyclic base consisting of polymer complexes ( 9)+( 10), and in monouclear compounds ( 6)-( 8), it behaves as a monobasic bidentate ligand coordinating through the same donor atoms. In mononuclear compounds ( 13)+( 14) it acts as a monobasic and neutral bidentate ligand coordinating only through the same donor atoms. Monomeric distorted octahedral or trimeric chlorine-bridged, approximately octahedral structures are proposed for these polymer complexes. The poly-chelates are of 1:1, 1:2 and 3:2 (metal-homopolymer) stoichiometry and exhibit six coordination. The values of ligand field parameters were calculated. The homopolymer and their polymer complexes have been characterized physicochemically.

  9. Functional tetrametallic linker modules for coordination polymers and metal-organic frameworks.

    PubMed

    Johansson, Frank B; Bond, Andrew D; McKenzie, Christine J

    2007-03-19

    The new biphenol-based tetranucleating ligand, 2,2',6,6'-tetrakis(N,N-bis(2-pyridylmethyl)aminomethyl)-4,4'-biphenolate, dbpbp2-, comprises two linearly disposed phenolato-hinged dinucleating heptadentate units, each of which offer one O and three N donors to a total of four metal ions. The ligand has been isolated as the zinc chloride complex [Zn4(dbpbp)Cl4]2+, and the ZnII ions have been completely or partially substituted by CuII, FeIII, CoII, and CoIII in metathesis reactions. Similarly, the chloride ligands of [Zn4(dbpbp)Cl4]2+ have been exchanged for solvent molecules (acetonitrile and/or water) and bridging carboxylate ligands. The resulting complexes have been characterized by single-crystal X-ray diffraction, ESI mass spectrometry (ESI-MS), cyclic voltammetry (CV), and EPR spectroscopy. The structures containing [M4(dbpbp)Cl4]2+ with M = ZnII or CuII exhibit 2-D polymeric honeycomb sheets in which intermolecular M...Cl interactions bridge between adjacent [M4(dbpbp)Cl4]2+ cations. Two mixed-metal tetrabenzoate complexes [M4(dbpbp)(O2CC6H5)4]2+/3+ have also been prepared, namely a stoichiometric CuII2ZnII2 complex and a nonstoichiometric FeIII/ZnII system. In the latter case, ESI-MS identifies FeZn3, Fe2Zn2, and Zn4 species, and X-ray crystallography suggests an average composition of Fe0.8Zn3.2. Preparation of a CoII4 complex by metathesis was considerably more difficult than preparation of [Cu4(dbpbp)Cl4]2+, requiring both a large excess of the cobalt source and the presence of auxiliary benzoate. In the presence of 2 equiv of benzoate per starting [Zn4(dbpbp)Cl4]2+ unit and excess CoII, dioxygen binds as peroxide at each end of the molecule to give the CoIII4 complex [Co4(dbpbp)(O2)2(O2CC6H5)2]4+. This latter complex, together with new tetra- and hexametallic benzenedicarboxylato- and benzenetricarboxylato-bridged complexes of dinuclear [Co2(O2)(bpbp)]3+ units (bpbp- = 2,6-bis(N,N-bis-(2-pyridylmethyl)aminomethyl)-4-tert-butyl-phenolate), is a module for potential construction of 1-D and 2-D coordination polymers/metal-organic frameworks (MOFs) capable of reversible O2 binding. PMID:17315867

  10. Photo- and thermochromic and adsorption properties of porous coordination polymers based on bipyridinium carboxylate ligands.

    PubMed

    Toma, Oksana; Mercier, Nicolas; Allain, Magali; Kassiba, Abdel Adi; Bellat, Jean-Pierre; Weber, Guy; Bezverkhyy, Igor

    2015-09-21

    The zwitterionic bipyridinium carboxylate ligand 1-(4-carboxyphenyl)-4,4'-bipyridinium (hpc1) in the presence of 1,4-benzenedicarboxylate anions (BDC(2-)) and Zn(2+) ions affords three porous coordination polymers (PCPs): [Zn5(hpc1)2(BDC)4(HCO2)2]·2DMF·EtOH·H2O (1), [Zn3(hpc1)(BDC)2(HCO2)(OH)(H2O)]·DMF·EtOH·H2O (2), and [Zn10(hpc1)4(BDC)7(HCO2)2(OH)4(EtOH)2]·3DMF·3H2O (3), with the formate anions resulting from the in situ decomposition of dimethylformamide (DMF) solvent molecules. 1 and 3 are photo- and thermochromic, turning dark green as a result of the formation of bipyridinium radicals, as shown by electron paramagnetic resonance measurements. Particularly, crystals of 3 are very photosensitive, giving an eye-detectable color change upon exposure to the light of the microscope in air within 1-2 min. A very nice and interesting feature is the regular discoloration of crystals from the "edge" to the "core" upon exposition to O2 (reoxidation of organic radicals) due to the diffusion of O2 inside the pores, with this discoloration being slower in an oxygen-poor atmosphere. The formation of organic radicals is explained by an electron transfer from the oxygen atoms of the carboxylate groups to pyridinium cycles. In the structure of 3', [Zn10(hpc1)4(BDC)7(OH)6(H2O)2], resulting from the heating of sample 3 (desolvation and loss of CO molecules due to the decomposition of formate anions), no suitable donor-acceptor interaction is present, and as a consequence, this compound does not exhibit any chromic properties. The presence of permanent porosity in desolvated 1, 2, and 3' is confirmed by methanol adsorption at 25 °C with the adsorbed amount reaching 5 wt % for 1, 10 wt % for 3', and 13 wt % for 2. The incomplete desorption of methanol at 25 °C under vacuum points to strong host-guest interactions. PMID:26370743

  11. Defect-induced effects on carrier migration through one-dimensional poly(para-phenylenevinylene) chains

    NASA Astrophysics Data System (ADS)

    Zoppi, L.; Calzolari, A.; Ruini, A.; Ferretti, A.; Caldas, M. J.

    2008-10-01

    Defects in one-dimensional (1D) systems can be intrinsically distinct from its three-dimensional counterparts, and polymer films are good candidates for showing both extremes that are difficult to individuate in the experimental data. We study theoretically the impact of simple hydrogen and oxygen defects on the electron transport properties of one-dimensional poly(para-phenylenevinylene) chains through a multiscale technique, starting from classical structural simulations for crystalline films to extensive ab initio calculations within density functional theory for the defects in single crystalline-constrained chains. The most disruptive effect on carrier transport comes from conjugation breaking imposed by the overcoordination of a carbon atom in the vinyl group independently from the chemical nature of the defect. The particular case of the [C=O] (keto-defect) shows in addition unexpected electron-hole separation, suggesting that the experimentally detected photoluminescence bleaching and photoconductivity enhancement could be due to exciton dissociation caused by the 1D characteristics of the defect.

  12. Progress on one-dimensional zinc oxide nanomaterials based photonic devices

    NASA Astrophysics Data System (ADS)

    Willander, Magnus; Israr, Muhammad Q.; Sadaf, Jamil R.; Nur, Omer

    2012-07-01

    One-dimensional nanostructures hold the most attractive and excellent physiochemical characteristics which exhibit the paramount influence on the fundamental and technological nanoelectronic as well as nanophotonic applications. In this review article, we present a detailed introduction to the diverse synthetic procedures which can be utilized for the fabrication of single-, planar- and three-dimensional ZnO nanostructures. More specifically, a thorough discussion regarding luminescence characteristics of the one-dimensional ZnO nanostructures is presented for ultraviolet and visible regions. We summarize the room temperature spontaneous emission and stimulated emission along with the interaction of the incident beam with material cavity to produce resonant optical modes and low-temperature time resolved photoluminescence studies. The most recent published results on the white light emitting diodes fabricated with the combination of ZnO nanotubes with p-GaN and ZnO nanorods with p-organic polymers on glass and disposable paper are discussed. Additionally, the significant results on optically and electrically pumped lasers are discussed; along with an overview on the future of ZnO nanostructures based photonic devices.

  13. Users manual for a one-dimensional Lagrangian transport model

    USGS Publications Warehouse

    Schoellhamer, D.H.; Jobson, H.E.

    1986-01-01

    A Users Manual for the Lagrangian Transport Model (LTM) is presented. The LTM uses Lagrangian calculations that are based on a reference frame moving with the river flow. The Lagrangian reference frame eliminates the need to numerically solve the convective term of the convection-diffusion equation and provides significant numerical advantages over the more commonly used Eulerian reference frame. When properly applied, the LTM can simulate riverine transport and decay processes within the accuracy required by most water quality studies. The LTM is applicable to steady or unsteady one-dimensional unidirectional flows in fixed channels with tributary and lateral inflows. Application of the LTM is relatively simple and optional capabilities improve the model 's convenience. Appendices give file formats and three example LTM applications that include the incorporation of the QUAL II water quality model 's reaction kinetics into the LTM. (Author 's abstract)

  14. One-dimensional planar hydrodynamic theory of shock ignition

    SciTech Connect

    Nora, R.; Betti, R.

    2011-08-15

    A one-dimensional planar compressible-piston-like model is used to investigate the basic physics behind shock-ignition inertial confinement fusion implosions. We discuss the theoretical limit set by rarefaction waves on the maximum hot-spot pressure achievable through conventional compression. Three ignitor shock techniques are presented to mitigate the effects of rarefaction waves, enhance the stagnation hot-spot pressure, and improve the ignition conditions. Elimination of rarefaction waves can lead to an {approx}80% increase in peak implosion pressures, while implosions augmented with ignitor shocks are shown to increase the peak pressures by a factor of {approx}4. These techniques are then discussed and the optimal energy ratio between the initial shell kinetic energy and the ignitor pulse energy is given.

  15. One-dimensional hybrid nanostructures for heterogeneous photocatalysis and photoelectrocatalysis.

    PubMed

    Xiao, Fang-Xing; Miao, Jianwei; Tao, Hua Bing; Hung, Sung-Fu; Wang, Hsin-Yi; Yang, Hong Bin; Chen, Jiazang; Chen, Rong; Liu, Bin

    2015-05-13

    Semiconductor-based photocatalysis and photoelectrocatalysis have received considerable attention as alternative approaches for solar energy harvesting and storage. The photocatalytic or photoelectrocatalytic performance of a semiconductor is closely related to the design of the semiconductor at the nanoscale. Among various nanostructures, one-dimensional (1D) nanostructured photocatalysts and photoelectrodes have attracted increasing interest owing to their unique optical, structural, and electronic advantages. In this article, a comprehensive review of the current research efforts towards the development of 1D semiconductor nanomaterials for heterogeneous photocatalysis and photoelectrocatalysis is provided and, in particular, a discussion of how to overcome the challenges for achieving full potential of 1D nanostructures is presented. It is anticipated that this review will afford enriched information on the rational exploration of the structural and electronic properties of 1D semiconductor nanostructures for achieving more efficient 1D nanostructure-based photocatalysts and photoelectrodes for high-efficiency solar energy conversion. PMID:25641821

  16. Asymptotics of one-dimensional forest fire processes

    E-print Network

    Xavier Bressaud; Nicolas Fournier

    2010-11-05

    We consider the so-called one-dimensional forest fire process. At each site of $\\mathbb{Z}$, a tree appears at rate $1$. At each site of $\\mathbb{Z}$, a fire starts at rate ${\\lambda}>0$, immediately destroying the whole corresponding connected component of trees. We show that when ${\\lambda}$ is made to tend to $0$ with an appropriate normalization, the forest fire process tends to a uniquely defined process, the dynamics of which we precisely describe. The normalization consists of accelerating time by a factor $\\log(1/{\\lambda})$ and of compressing space by a factor ${\\lambda}\\log(1/{\\lambda})$. The limit process is quite simple: it can be built using a graphical construction and can be perfectly simulated. Finally, we derive some asymptotic estimates (when ${\\lambda}\\to0$) for the cluster-size distribution of the forest fire process.

  17. Light Field Distributions in One-dimensional Photonic Crystal Fibers

    E-print Network

    Changbiao Wang

    2011-01-22

    It is shown in this paper that the light field distribution in a band gap within periodic structures for one-dimensional photonic crystal fibers is described by a decaying factor multiplied by a periodical function that has the same period length as the one of the medium or has double the period length of the medium, depending on the sign of the trace of eigen value matrix. This fundamental property is applicable to any 1D planar periodic structures, no matter how many layers a unit cell has, what the contrast of refractive indices is, and whether the dielectric parameters in individual layers are homogeneous or inhomogeneous; it plays a significant role in understanding of numerical results in a number of previously published research works. It is also shown that, similar to the refractive index guidance in conventional optical fibers, the photonic band gap guidance is also a form of total internal reflection.

  18. Luminescent one-dimensional nanostructures of perylene bisimides.

    PubMed

    Boobalan, G; Imran, P K M; Nagarajan, S

    2013-09-01

    Perylene bisimides form a unique class of organic semiconductors, in this investigation two symmetrical perylene bisimides caped with 1-butyl (B-PTCDI) and 4,4-diethoxybutyl (DB-PTCDI) have been synthesized and characterized. The compounds self-assembled as a network of nanobelts and nanorods in the solution based self-assembly process. Morphologies of these self-assembled structures were characterized by optical, fluorescence, scanning and transmission electronic microscopic techniques. One-dimensional self-assemblies of B-PTCDI and DB-PTCDI molecules are due to the strong ?-? stacking ability of perylene core and assistance given by the side chains and solvent. Observed molecular self-assembly and electronic properties of the molecules. The observed self-assembly was supported by molecular modeling studies using density functional theory. PMID:23743040

  19. One-dimensional modeling of piping flow erosion

    NASA Astrophysics Data System (ADS)

    Lachouette, Damien; Golay, Frédéric; Bonelli, Stéphane

    2008-09-01

    A process called "piping", which often occurs in water-retaining structures (earth-dams, dykes, levees), involving the formation and progression of a continuous tunnel between the upstream and downstream sides, is one of the main cause of structure failure. Starting with the diphasic flow volume equations and the jump equations including the erosion processes, a simplified one-dimensional model for two-phase piping flow erosion was developed. The numerical simulation based on constant input and output pressures showed that the particle concentration can be a significant factor at the very beginning of the process, resulting in the enlargement of the hole at the exit. However, it was concluded that this influence is a secondary factor: the dilute flow assumption, which considerably simplifies the description, is relevant here. To cite this article: D. Lachouette et al., C. R. Mecanique 336 (2008).

  20. Magnons in one-dimensional k-component Fibonacci structures

    SciTech Connect

    Costa, C. H.; Vasconcelos, M. S.

    2014-05-07

    We have studied the magnon transmission through of one-dimensional magnonic k-component Fibonacci structures, where k different materials are arranged in accordance with the following substitution rule: S{sub n}{sup (k)}=S{sub n?1}{sup (k)}S{sub n?k}{sup (k)}?(n?k=0,1,2,…), where S{sub n}{sup (k)} is the nth stage of the sequence. The calculations were carried out in exchange dominated regime within the framework of the Heisenberg model and taking into account the RPA approximation. We have considered multilayers composed of simple cubic spin-S Heisenberg ferromagnets, and, by using the powerful transfer-matrix method, the spin wave transmission is obtained. It is demonstrated that the transmission coefficient has a rich and interesting magnonic pass- and stop-bands structures, which depends on the frequency of magnons and the k values.

  1. Quantum quenches and thermalization in one-dimensional fermionic systems

    NASA Astrophysics Data System (ADS)

    Rigol, Marcos

    2009-11-01

    We study the dynamics and thermalization of strongly correlated fermions in finite one-dimensional lattices after a quantum quench. Our calculations are performed using exact diagonalization. We focus on one- and two-body observables such as the momentum distribution function [n(k)] and the density-density structure factor [N(k)] , respectively, and study the effects of approaching an integrable point. We show that while the relaxation dynamics and thermalization of N(k) for fermions is very similar to the one of hardcore bosons, the behavior of n(k) is distinctively different. The latter observable exhibits a slower relaxation dynamics in fermionic systems. We identify the origin of this behavior, which is related to the off-diagonal matrix elements of n(k) in the basis of the eigenstates of the Hamiltonian. More generally, we find that thermalization occurs far away from integrability and that it breaks down as one approaches the integrable point.

  2. Strongly-Refractive One-Dimensional Photonic Crystal Prisms

    NASA Technical Reports Server (NTRS)

    Ting, David Z. (Inventor)

    2004-01-01

    One-dimensional (1D) photonic crystal prisms can separate a beam of polychromatic electromagnetic waves into constituent wavelength components and can utilize unconventional refraction properties for wavelength dispersion over significant portions of an entire photonic band rather than just near the band edges outside the photonic band gaps. Using a ID photonic crystal simplifies the design and fabrication process and allows the use of larger feature sizes. The prism geometry broadens the useful wavelength range, enables better optical transmission, and exhibits angular dependence on wavelength with reduced non-linearity. The properties of the 1 D photonic crystal prism can be tuned by varying design parameters such as incidence angle, exit surface angle, and layer widths. The ID photonic crystal prism can be fabricated in a planar process, and can be used as optical integrated circuit elements.

  3. Properties of surface modes in one dimensional plasma photonic crystals

    SciTech Connect

    Shukla, S.; Prasad, S. Singh, V.

    2015-02-15

    Properties of surface modes supported at the interface of air and a semi-infinite one dimensional plasma photonic crystal are analyzed. The surface mode equation is obtained by using transfer matrix method and applying continuity conditions of electric fields and its derivatives at the interface. It is observed that with increase in the width of cap layer, frequencies of surface modes are shifted towards lower frequency side, whereas increase in tangential component of wave-vector increases the mode frequency and total energy carried by the surface modes. With increase in plasma frequency, surface modes are found to shift towards higher frequency side. The group velocity along interface is found to control by cap layer thickness.

  4. Experiment and simulation on one-dimensional plasma photonic crystals

    SciTech Connect

    Zhang, Lin; Ouyang, Ji-Ting

    2014-10-15

    The transmission characteristics of microwaves passing through one-dimensional plasma photonic crystals (PPCs) have been investigated by experiment and simulation. The PPCs were formed by a series of discharge tubes filled with argon at 5?Torr that the plasma density in tubes can be varied by adjusting the discharge current. The transmittance of X-band microwaves through the crystal structure was measured under different discharge currents and geometrical parameters. The finite-different time-domain method was employed to analyze the detailed properties of the microwaves propagation. The results show that there exist bandgaps when the plasma is turned on. The properties of bandgaps depend on the plasma density and the geometrical parameters of the PPCs structure. The PPCs can perform as dynamical band-stop filter to control the transmission of microwaves within a wide frequency range.

  5. One-dimensional photonic crystal fishbone hybrid nanocavity with nanoposts

    SciTech Connect

    Lu, Tsan-Wen; Lin, Pin-Tso; Lee, Po-Tsung

    2014-05-12

    We propose and investigate a one-dimensional photonic crystal (PhC) fishbone (FB) hybrid nanocavity lying on silver substrate with a horizontal air slot. With very few PhC periods, the confined transverse-magnetic, TM{sub 10} hybrid mode concentrated within the air slot shows high quality factor over effective mode volume ratio larger than 10{sup 5}?{sup ?3}. Most importantly, this FB hybrid nanocavity allows formation of low-index nanoposts within the air slot without significantly affecting the mode properties. These nanoposts guarantee the structural stabilities under different environmental perturbations. Furthermore, capabilities of our proposed design in serving as optical sensors and tweezers for bio-sized nanoparticles are also investigated.

  6. Majorana fermion exchange in strictly one-dimensional structures

    NASA Astrophysics Data System (ADS)

    Chiu, Ching-Kai; Vazifeh, M. M.; Franz, M.

    2015-04-01

    It is generally thought that the adiabatic exchange of two identical particles is impossible in one spatial dimension. Here we describe a simple protocol that permits the adiabatic exchange of two Majorana fermions in a one-dimensional topological superconductor wire. The exchange relies on the concept of “Majorana shuttle” whereby a ? domain wall in the superconducting order parameter which hosts a pair of ancillary majoranas delivers one zero mode across the wire while the other one tunnels in the opposite direction. The method requires some tuning of parameters and does not, therefore, enjoy full topological protection. The resulting exchange statistics, however, remain non-Abelian for a wide range of parameters that characterize the exchange.

  7. Counter Chemotactic Flow in Quasi-One-Dimensional Path

    NASA Astrophysics Data System (ADS)

    Fujii, Masashi; Awazu, Akinori; Nishimori, Hiraku

    2009-07-01

    Quasi-one-dimensional bidirectional particle flow including the effect of chemotaxis is investigated through a modification of the John-Schadschneider-Chowdhury-Nishinari model. Specifically, we permit multiple lanes to be shared by both directionally traveling particles. The relation between particle density and flux is studied for several evaporation rates of pheromone, and the following results are obtained: i) in the low-particle-density range, the flux is enlarged by pheromone if the pheromone evaporation rate is sufficiently low, ii) in the high particle-density range, the flux is largest at a reasonably high evaporation rate and, iii) if the evaporation rate is at the level intermediate between the above two cases, the flux is kept small in the entire range of particle densities. The mechanism of these behaviors is investigated by observing the spatiotemporal evolution of particles and the average cluster size in the system.

  8. One-Dimensional Time to Explosion (Thermal Sensitivity) of ANPZ

    SciTech Connect

    Hsu, P.; Hust, G.; McClelland, M.; Gresshoff, M.

    2014-11-12

    Incidents caused by fire and combat operations can heat energetic materials that may lead to thermal explosion and result in structural damage and casualty. Some explosives may thermally explode at fairly low temperatures (< 100 C) and the violence from thermal explosion may cause a significant damage. Thus it is important to understand the response of energetic materials to thermal insults. The One Dimensional Time to Explosion (ODTX) system at the Lawrence Livermore National Laboratory has been used for decades to measure times to explosion, threshold thermal explosion temperature, and determine kinetic parameters of energetic materials. Samples of different configurations (pressed part, powder, paste, and liquid) can be tested in the system. The ODTX testing can also provide useful data for assessing the thermal explosion violence of energetic materials. This report summarizes the recent ODTX experimental data and modeling results for 2,6-diamino-3,5-dintropyrazine (ANPZ).

  9. Quasi one dimensional transport in individual electrospun composite nanofibers

    SciTech Connect

    Avnon, A. Datsyuk, V.; Trotsenko, S.; Wang, B.; Zhou, S.

    2014-01-15

    We present results of transport measurements of individual suspended electrospun nanofibers Poly(methyl methacrylate)-multiwalled carbon nanotubes. The nanofiber is comprised of highly aligned consecutive multiwalled carbon nanotubes. We have confirmed that at the range temperature from room temperature down to ?60 K, the conductance behaves as power-law of temperature with an exponent of ? ? 2.9?10.2. The current also behaves as power law of voltage with an exponent of ? ? 2.3?8.6. The power-law behavior is a footprint for one dimensional transport. The possible models of this confined system are discussed. Using the model of Luttinger liquid states in series, we calculated the exponent for tunneling into the bulk of a single multiwalled carbon nanotube ?{sub bulk} ? 0.06 which agrees with theoretical predictions.

  10. Quasi one dimensional transport in individual electrospun composite nanofibers

    NASA Astrophysics Data System (ADS)

    Avnon, A.; Wang, B.; Zhou, S.; Datsyuk, V.; Trotsenko, S.; Grabbert, N.; Ngo, H.-D.

    2014-01-01

    We present results of transport measurements of individual suspended electrospun nanofibers Poly(methyl methacrylate)-multiwalled carbon nanotubes. The nanofiber is comprised of highly aligned consecutive multiwalled carbon nanotubes. We have confirmed that at the range temperature from room temperature down to ˜60 K, the conductance behaves as power-law of temperature with an exponent of ? ˜ 2.9-10.2. The current also behaves as power law of voltage with an exponent of ? ˜ 2.3-8.6. The power-law behavior is a footprint for one dimensional transport. The possible models of this confined system are discussed. Using the model of Luttinger liquid states in series, we calculated the exponent for tunneling into the bulk of a single multiwalled carbon nanotube ?bulk ˜ 0.06 which agrees with theoretical predictions.

  11. Anomalous heat conduction and anomalous diffusion in one dimensional systems

    E-print Network

    Baowen Li; Jiao Wang

    2003-06-23

    We establish a connection between anomalous heat conduction and anomalous diffusion in one dimensional systems. It is shown that if the mean square of the displacement of the particle is $ =2Dt^{\\alpha} (0conductivity can be expressed in terms of the system size $L$ as $\\kappa = cL^{\\beta}$ with $\\beta=2-2/\\alpha$. This result predicts that a normal diffusion ($\\alpha =1$) implies a normal heat conduction obeying the Fourier law ($\\beta=0$), a superdiffusion ($\\alpha>1$) implies an anomalous heat conduction with a divergent thermal conductivity ($\\beta>0$), and more interestingly, a subdiffusion ($\\alpha heat conduction with a convergent thermal conductivity ($\\beta<0$), consequently, the system is a thermal insulator in the thermodynamic limit. Existing numerical data support our results.

  12. Switching synchronization in one-dimensional memristive networks

    NASA Astrophysics Data System (ADS)

    Slipko, Valeriy A.; Shumovskyi, Mykola; Pershin, Yuriy V.

    2015-11-01

    We report on a switching synchronization phenomenon in one-dimensional memristive networks, which occurs when several memristive systems with different switching constants are switched from the high- to low-resistance state. Our numerical simulations show that such a collective behavior is especially pronounced when the applied voltage slightly exceeds the combined threshold voltage of memristive systems. Moreover, a finite increase in the network switching time is found compared to the average switching time of individual systems. An analytical model is presented to explain our observations. Using this model, we have derived asymptotic expressions for memory resistances at short and long times, which are in excellent agreement with results of our numerical simulations.

  13. Erosion by a one-dimensional random walk

    NASA Astrophysics Data System (ADS)

    Chisholm, Rebecca H.; Hughes, Barry D.; Landman, Kerry A.

    2014-08-01

    We consider a model introduced by Baker et al. [Phys. Rev. E 88, 042113 (2013), 10.1103/PhysRevE.88.042113] of a single lattice random walker moving on a domain of allowed sites, surrounded by blocked sites. The walker enlarges the allowed domain by eroding the boundary at its random encounters with blocked boundary sites: attempts to step onto blocked sites succeed with a given probability and convert these sites to allowed sites. The model interpolates continuously between the Pólya random walker on the one-dimensional lattice and a "blind" walker who attempts freely, but always aborts, moves to blocked sites. We obtain some exact results about the walker's location and the rate of erosion.

  14. Practical variational tomography for critical one-dimensional systems

    NASA Astrophysics Data System (ADS)

    Lee, Jong Yeon; Landon-Cardinal, Olivier

    2015-06-01

    We improve upon a recently introduced efficient quantum state reconstruction procedure targeted to states well approximated by the multiscale entanglement renormalization ansatz (MERA), e.g., ground states of critical models. We show how to numerically select a subset of experimentally accessible measurements which maximize information extraction about renormalized particles, thus dramatically reducing the required number of physical measurements. We numerically estimate the number of measurements required to characterize the ground state of the critical one-dimensional Ising (resp. XX) model and find that MERA tomography on 16-qubit (resp. 24-qubit) systems requires the same experimental effort as brute-force tomography on 8 qubits. We derive a bound computable from experimental data which certifies the distance between the experimental and reconstructed states.

  15. Absorbing/emitting phonons with one dimensional MOSFETs

    NASA Astrophysics Data System (ADS)

    Bosisio, Riccardo; Gorini, Cosimo; Fleury, Geneviève; Pichard, Jean-Louis

    2015-11-01

    We consider nanowires in the field effect transistor device configuration. Modeling each nanowire as a one dimensional lattice with random site potentials, we study the heat exchanges between the nanowire electrons and the substrate phonons, when electron transport is due to phonon-assisted hops between localized states. Shifting the nanowire conduction band with a metallic gate induces different behaviors. When the Fermi potential is located near the band center, a bias voltage gives rise to small local heat exchanges which fluctuate randomly along the nanowire. When it is located near one of the band edges, the bias voltage yields heat currents which flow mainly from the substrate towards the nanowire near one boundary of the nanowire, and in the opposite direction near the other boundary. This opens interesting perspectives for heat management at submicron scales: arrays of parallel gated nanowires could be used for a field control of phonon emission/absorption.

  16. Loschmidt echo in one-dimensional interacting Bose gases

    SciTech Connect

    Lelas, K.; Seva, T.; Buljan, H.

    2011-12-15

    We explore Loschmidt echo in two regimes of one-dimensional interacting Bose gases: the strongly interacting Tonks-Girardeau (TG) regime, and the weakly interacting mean-field regime. We find that the Loschmidt echo of a TG gas decays as a Gaussian when small (random and time independent) perturbations are added to the Hamiltonian. The exponent is proportional to the number of particles and the magnitude of a small perturbation squared. In the mean-field regime the Loschmidt echo shows richer behavior: it decays faster for larger nonlinearity, and the decay becomes more abrupt as the nonlinearity increases; it can be very sensitive to the particular realization of the noise potential, especially for relatively small nonlinearities.

  17. Topological phase transition in quasi-one dimensional organic conductors.

    PubMed

    Ye, Xiao-Shan; Liu, Yong-Jun; Zeng, Xiang-Hua; Wu, Guoqing

    2015-01-01

    We explore topological phase transition, which involves the energy spectra of field-induced spin-density-wave (FISDW) states in quasi-one dimensional (Q1D) organic conductors, using an extended Su-Schrieffer-Heeger (SSH) model. We show that, in presence of half magnetic-flux FISDW state, the system exhibits topologically nontrivial phases, which can be characterized by a nonzero Chern number. The nontrivial evolution of the bulk bands with chemical potential in a topological phase transition is discussed. We show that the system can have a similar phase diagram which is discussed in the Haldane's model. We suggest that the topological feature should be tested experimentally in this organic system. These studies enrich the theoretical research on topologically nontrivial phases in the Q1D lattice system as compared to the Haldane topological phase appearing in the two-dimensional lattices. PMID:26612317

  18. Efficient algorithm for approximating one-dimensional ground states

    SciTech Connect

    Aharonov, Dorit; Arad, Itai; Irani, Sandy

    2010-07-15

    The density-matrix renormalization-group method is very effective at finding ground states of one-dimensional (1D) quantum systems in practice, but it is a heuristic method, and there is no known proof for when it works. In this article we describe an efficient classical algorithm which provably finds a good approximation of the ground state of 1D systems under well-defined conditions. More precisely, our algorithm finds a matrix product state of bond dimension D whose energy approximates the minimal energy such states can achieve. The running time is exponential in D, and so the algorithm can be considered tractable even for D, which is logarithmic in the size of the chain. The result also implies trivially that the ground state of any local commuting Hamiltonian in 1D can be approximated efficiently; we improve this to an exact algorithm.

  19. Exact semiclassical expansions for one-dimensional quantum oscillators

    SciTech Connect

    Delabaere, E.; Dillinger, H.; Pham, F.

    1997-12-01

    A set of rules is given for dealing with WKB expansions in the one-dimensional analytic case, whereby such expansions are not considered as approximations but as exact encodings of wave functions, thus allowing for analytic continuation with respect to whichever parameters the potential function depends on, with an exact control of small exponential effects. These rules, which include also the case when there are double turning points, are illustrated on various examples, and applied to the study of bound state or resonance spectra. In the case of simple oscillators, it is thus shown that the Rayleigh{endash}Schr{umlt o}dinger series is Borel resummable, yielding the exact energy levels. In the case of the symmetrical anharmonic oscillator, one gets a simple and rigorous justification of the Zinn-Justin quantization condition, and of its solution in terms of {open_quotes}multi-instanton expansions.{close_quotes} {copyright} {ital 1997 American Institute of Physics.}

  20. Sonic black holes in a one-dimensional relativistic flow

    NASA Astrophysics Data System (ADS)

    Carbonaro, P.

    2015-09-01

    The analogy between sound propagation in a fluid background and light propagation in a curved spacetime, discovered by Unruh in 1981, does not work in general when considering the motion of a fluid which is confined in one spatial dimension being unable in (1+1) dimensions to introduce in a coherent manner an effective acoustic metric, barring some exceptional cases. In this paper a relativistic fluid is considered and the general condition for the existence of an acoustic metric in strictly one-dimensional systems is found. Attention is also paid to the physical meaning of the equations of state characterizing such systems and to the remarkable symmetry of structure taken by the basic equations. Finally the Hawking temperature is calculated in an artificial de Laval nozzle.

  1. Mode engineering with a one-dimensional superconducting metamaterial

    NASA Astrophysics Data System (ADS)

    Taguchi, Masahiko; Basko, Denis M.; Hekking, Frank W. J.

    2015-07-01

    We propose a way to control the Josephson energy of a single Josephson junction embedded in a one-dimensional superconducting metamaterial: an inhomogeneous superconducting loop, made out of a superconducting nanowire or a chain of Josephson junctions. The Josephson energy is renormalized by the electromagnetic modes propagating along the loop. We study the behavior of the modes as well as of their frequency spectrum when the capacitance and the inductance along the loop are spatially modulated. We show that, depending on the amplitude of the modulation, the renormalized Josephson energy is either larger or smaller than the one found for a homogeneous loop. Using typical experimental parameters for Josephson junction chains and superconducting nanowires, we conclude that this mode engineering can be achieved with currently available metamaterials.

  2. Spin-Imbalance in a One-Dimensional Fermi Gas

    E-print Network

    Liao, Yean-an; Paprotta, Tobias; Li, Wenhui; Partridge, Guthrie B; Hulet, Randall G; Baur, Stefan K; Mueller, Erich J

    2009-01-01

    Superconductivity and magnetism generally do not coexist. Changing the relative number of up and down spin electrons disrupts the basic mechanism of superconductivity, where atoms of opposite momentum and spin form Cooper pairs. Nearly forty years ago Fulde and Ferrell and Larkin and Ovchinnikov proposed an exotic pairing mechanism (FFLO) where magnetism is accommodated by formation of pairs with finite momentum. Despite intense theoretical and experimental efforts, however, polarized superconductivity remains largely elusive. Here we report experimental measurements of density profiles of a two spin mixture of ultracold 6Li atoms trapped in an array of one dimensional (1D) tubes, a system analogous to electrons in 1D wires. At finite spin imbalance, the system phase separates with an inverted phase profile in comparison to the three-dimensional case. In 1D we find a partially polarized core surrounded by wings composed of either a completely paired BCS superfluid or a fully polarized Fermi gas, depending on ...

  3. Topological phase transition in quasi-one dimensional organic conductors

    PubMed Central

    Ye, Xiao-Shan; Liu, Yong-Jun; Zeng, Xiang-Hua; Wu, Guoqing

    2015-01-01

    We explore topological phase transition, which involves the energy spectra of field-induced spin-density-wave (FISDW) states in quasi-one dimensional (Q1D) organic conductors, using an extended Su-Schrieffer-Heeger (SSH) model. We show that, in presence of half magnetic-flux FISDW state, the system exhibits topologically nontrivial phases, which can be characterized by a nonzero Chern number. The nontrivial evolution of the bulk bands with chemical potential in a topological phase transition is discussed. We show that the system can have a similar phase diagram which is discussed in the Haldane’s model. We suggest that the topological feature should be tested experimentally in this organic system. These studies enrich the theoretical research on topologically nontrivial phases in the Q1D lattice system as compared to the Haldane topological phase appearing in the two-dimensional lattices. PMID:26612317

  4. One-dimensional optical lattices and impenetrable bosons

    SciTech Connect

    Cazalilla, M.A. |

    2003-05-01

    We study the limit of large on-site repulsion of the one-dimensional Bose-Hubbard model at low densities, and derive a strong-coupling effective Hamiltonian. By taking the lattice parameter to zero, the Hamiltonian becomes a continuum model of fermions with attractive interactions. The leading corrections to the internal energy of a hard-core-boson (Tonks) gas as well as the (finite temperature) pair correlations of a strongly interacting Bose gas are calculated. We explore the possibility of realizing, in an optical lattice, a Luttinger liquid with stronger density correlations than the Tonks gas. A quantum phase transition to a charge-density-wave Mott insulator is also discussed.

  5. Lattice Wave Transmission Through One-Dimensional Defected Chain

    NASA Astrophysics Data System (ADS)

    Liu, Hong

    By using Green's functional method, we investigated the influence of different strength constants at defected bonds and the junction's size on the transmission properties of the lattice wave in a one-dimensional chain. The heat currents of several defected chains are also calculated. The results show that correlation transmission between two defected bonds in a chain different from electron behaviors. Furthermore, for a large-size junction embedded in a chain, the transmission of high frequency phonons will disappear while having smaller strength constant in the junction than in two semi-infinity chains. On the other hand, for larger strength constant than in two semi-infinite chains, all phonons can transport through the junction with a certain transmission value, although the number of transmission peaks decreases. Finally, the lower frequency lattice waves have better transmission through a junction with a series of strength constants according to the Fibonacci sequence.

  6. Microwave properties of nonlinear one-dimensional quasiperiodic photonic crystals

    NASA Astrophysics Data System (ADS)

    Trabelsi, Y.; Kanzari, M.

    2012-06-01

    The nonlinear properties of quasi-periodic photonic crystals based on the Thue-Morse and Fibonacci sequence are investigated. We address the transmission properties of waves through one dimensional symmetric Fibonacci, and Thue-Morse system i.e., a quasiperiodic structure made up of two different dielectric materials (Rogers and air), in quarter wavelength condition, presenting in the one directions. The microwave spectra are calculated by using transfer matrix method in normal incidence geometry. In our results we present the self-similar features of the spectra and we also present the microwave properties through a return map of the transmission coefficients. We extract powerfully the band gaps of quasi-periodic multilayered structures, called `pseudo band gaps' often contain resonant states, which can be considered as a manifestation of numerous defects distributed along the structure. Taken together, the above two properties provide favorable conditions for the design of an all-microwave reflector.

  7. Magnetic properties of manganese based one-dimensional spin chains.

    PubMed

    Asha, K S; Ranjith, K M; Yogi, Arvind; Nath, R; Mandal, Sukhendu

    2015-11-18

    We have correlated the structure-property relationship of three manganese-based inorganic-organic hybrid structures. Compound , [Mn2(OH-BDC)2(DMF)3] (where BDC = 1,4-benzene dicarboxylic acid and DMF = N,N'-dimethylformamide), contains Mn2O11 dimers as secondary building units (SBUs), which are connected by carboxylate anions forming Mn-O-C-O-Mn chains. Compound , [Mn2(BDC)2(DMF)2], contains Mn4O20 clusters as SBUs, which also form Mn-O-C-O-Mn chains. In compound , [Mn3(BDC)3(DEF)2] (where DEF = N,N'-diethylformamide), the distorted MnO6 octahedra are linked to form a one-dimensional chain with Mn-O-Mn connectivity. The magnetic properties were investigated by means of magnetization and heat capacity measurements. The temperature dependent magnetic susceptibility of all the three compounds could be nicely fitted using a one-dimensional S = 5/2 Heisenberg antiferromagnetic chain model and the value of intra-chain exchange coupling (J/kB) between Mn(2+) ions was estimated to be ?1.1 K, ?0.7 K, and ?0.46 K for compounds , , and , respectively. Compound does not undergo any magnetic long-range-order down to 2 K while compounds and undergo long-range magnetic order at TN ? 4.2 K and ?4.3 K, respectively, which are of spin-glass type. From the values of J/kB and TN the inter-chain coupling (J?/kB) was calculated to be about 0.1J/kB for both compounds and , respectively. PMID:26455515

  8. A One-Dimensional Synthetic-Aperture Microwave Radiometer

    NASA Technical Reports Server (NTRS)

    Doiron, Terence; Piepmeier, Jeffrey

    2010-01-01

    A proposed one-dimensional synthetic- aperture microwave radiometer could serve as an alternative to either the two-dimensional synthetic-aperture radiometer described in the immediately preceding article or to a prior one-dimensional one, denoted the Electrically Scanned Thinned Array Radiometer (ESTAR), mentioned in that article. The proposed radiometer would operate in a pushbroom imaging mode, utilizing (1) interferometric cross-track scanning to obtain cross-track resolution and (2) the focusing property of a reflector for along-track resolution. The most novel aspect of the proposed system would be the antenna (see figure), which would include a cylindrical reflector of offset parabolic cross section. The reflector could be made of a lightweight, flexible material amenable to stowage and deployment. Other than a stowage/deployment mechanism, the antenna would not include moving parts, and cross-track scanning would not entail mechanical rotation of the antenna. During operation, the focal line, parallel to the cylindrical axis, would be oriented in the cross-track direction, so that placement of receiving/radiating elements at the focal line would afford the desired along-track resolution. The elements would be microwave feed horns sparsely arrayed along the focal line. The feed horns would be oriented with their short and long cross-sectional dimensions parallel and perpendicular, respectively, to the cylindrical axis to obtain fan-shaped beams having their broad and narrow cross-sectional dimensions parallel and perpendicular, respectively, to the cylindrical axis. The interference among the beams would be controlled in the same manner as in the ESTAR to obtain along-cylindrical- axis (cross-track) resolution and cross-track scanning.

  9. One-dimensional cloud fluid model for propagating star formation

    NASA Technical Reports Server (NTRS)

    Titus, Timothy N.; Struck-Marcell, Curtis

    1990-01-01

    The aim of this project was to study the propagation of star formation (SF) with a self-consistent deterministic model for the interstellar gas. The questions of under what conditions does star formation propagate in this model and what are the mechanisms of the propagation are explored. Here, researchers used the deterministic Oort-type cloud fluid model of Scalo and Struck-Marcell (1984, also see the review of Struck-Marcell, Scalo and Appleton 1987). This cloud fluid approach includes simple models for the effects of cloud collisional coalescence or disruption, collisional energy dissipation, and cloud disruption and acceleration as the result of young star winds, HII regions and supernovae. An extensive one-zone parameter study is presented in Struck-Marcell and Scalo (1987). To answer the questions above, researchers carried out one-dimensional calculations for an annulus within a galactic disk, like the so-called solar neighborhood of the galactic chemical evolution. In the calculations the left-hand boundary is set equal to the right hand boundary. The calculation is obviously idealized; however, it is computationally convenient to study the first order effects of propagating star formation. The annulus was treated as if it were at rest, i.e., in the local rotating frame. This assumption may remove some interesting effects of a supersonic gas flow, but was necessary to maintain a numerical stability in the annulus. The results on the one-dimensional propagation of SF in the Oort cloud fluid model follow: (1) SF is propagated by means of hydrodynamic waves, which can be generated by external forces or by the pressure generated by local bursts. SF is not effectively propagated via diffusion or variation in cloud interaction rates without corresponding density and velocity changes. (2) The propagation and long-range effects of SF depend on how close the gas density is to the critical threshold value, i.e., on the susceptibility of the medium.

  10. Fullerene-based one-dimensional crystalline nanopolymer formed through topochemical transformation of the parent nanowire

    NASA Astrophysics Data System (ADS)

    Geng, Junfeng; Solov'Yov, Ilia A.; Reid, David G.; Skelton, Paul; Wheatley, Andrew E. H.; Solov'Yov, Andrey V.; Johnson, Brian F. G.

    2010-06-01

    Large-scale practical applications of fullerene (C60) in nanodevices could be significantly facilitated if the commercially available micrometer-scale raw C60 powder were further processed into a one-dimensional nanowire-related polymer displaying covalent bonding as molecular interlinks and resembling traditional important conjugated polymers. However, there has been little study thus far in this area despite the abundant literature on fullerene. Here we report the preparation and characterization of such a C60 -based polymer nanowire, (-C60TMB-)n , where TMB=1,2,4 -trimethylbenzene, which displays a well-defined crystalline nanostructure, exceptionally large length-to-width ratio and excellent thermal stability. The material is prepared by first growing the corresponding nanowire through a solution phase of C60 followed by a topochemical polymerization reaction in the solid state. Gas chromatography, mass spectrometry and C13 nuclear magnetic resonance evidence is provided for the nature of the covalent bonding mode adopted by the polymeric chains. Theoretical analysis based on detailed calculations of the reaction energetics and structural analysis provides an in-depth understanding of the polymerization pathway. The nanopolymer promises important applications in biological fields and in the development of optical, electrical, and magnetic nanodevices.

  11. Syntheses and structures of three heterometallic coordination polymers derived from 4-pyridin-3-yl-benzoic acid

    SciTech Connect

    Fang, Wei-Hui; Yang, Guo-Yu

    2014-04-01

    Three lanthanide–transition-metal coordination polymers, namely, [Er{sub 2}L{sub 6}(H{sub 2}O)][Cu{sub 2}I{sub 2}] (1), [ErL{sub 3}][CuI] (2), and [Dy{sub 2}L{sub 6}(BPDC){sub 0.5}(H{sub 2}O){sub 4}][Cu{sub 3}I{sub 2}] (3) (HL=4-pyridin-3-yl-benzoic acid, H{sub 2}BPDC=4,4?-biphenyldicarboxylic acid) have been made by reacting Ln{sub 2}O{sub 3} and CuI with HL at different temperatures under hydrothermal conditions. All the complexes are characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, powder X-ray diffraction, and single-crystal X-ray diffraction, respectively. 1–3 all construct from dimeric (Ln{sub 2}) and (Cu{sub 2}) units and exhibit two types of the structural features: 1 is a two-dimensional layer, 2–3 are three-dimensional frameworks. Interestingly, the in situ formation of the BPDC ligand is found in the structure of 3. The distinct architectures of these complexes indicated that the reaction temperature plays an important role in the formation of higher dimensional coordination polymers. - Graphical abstract: By hydrothermal reaction of lanthanide oxide, copper halide, and 4-pyridin-3-yl-benzoic ligand at different temperatures, a series of 1-D to 3-D 3d–4f coordination polymers, namely [ErL{sub 3}(H{sub 2}O){sub 2}][CuI], [Er{sub 2}L{sub 6}(H{sub 2}O)][Cu{sub 2}I{sub 2}], [ErL{sub 3}][CuI], and [Dy{sub 2}L{sub 6}(BPDC){sub 0.5}(H{sub 2}O){sub 4}][Cu{sub 3}I{sub 2}], have been made, respectively. - Highlights: • Three novel heterometallic coordination polymers derived from 4-pyridin-3-yl-benzoic acid have been hydrothermally synthesized. • Mixed dinuclear motifs of (Ln{sub 2}) and (Cu{sub 2}) serve as secondary building units to generate 2-D layer and 3-D frameworks. • It is proved that higher temperature is apt to permit construction of high dimensional architectures.

  12. Controlled formation of fluorescent metalloporphyrin-containing coordination polymer particles from seed structures by designed shape-transformation reactions.

    PubMed

    Sun, Yu; Li, Xiaopeng; Caravella, Alessio; Gao, Rongke

    2015-04-27

    Herein, nanorod structures and four-leaf clover structures of fluorescent zinc 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine (ZnTPyP)-containing coordination polymer particles (CPPs) were first synthesized by a bottom-up strategy assisted by surfactants and then employed as seed structures for further shape-transformation reactions. We have successfully designed the morphological transformation for different dimensions, achieving the controlled formation of octahedron structures at both the nanometer scale and micrometer scale from the seed structures. Our approach illustrates a new method to design and synthesize metalloporphyrin-containing CPPs in a systematic and controllable manner. PMID:25784091

  13. A homochiral luminescent 2D porous coordination polymer with collagen-type triple helices showing selective guest inclusion.

    PubMed

    Joarder, Biplab; Chaudhari, Abhijeet K; Ghosh, Sujit K

    2012-04-16

    A homochiral luminescent porous coordination polymer, [Cd(L)(H(2)O)]·3H(2)O, with interconnected collagen like triple-helical chains has been synthesized solvothermally by using cadmium(II) salt and a newly designed d-isosorbide-based, enantiomerically pure chiral ligand. The framework is a 2D porous material and forms a 1D channel along the a axis, with the channel dimensions ~6.2 × 4.4 Å(2). The compound has high selectivity in the uptake of water and methanol over other solvents (e.g., tetrahydrofuran, ethanol, benzene, and cyclohexane) inside the channels. PMID:22449177

  14. Photodecomposition of ferrocenedicarboxylic acid in methanol to form an electroactive infinite coordination polymer and its application in bioelectrochemistry.

    PubMed

    Zhang, Li; Gao, Xia; Yang, Lifen; Yu, Ping; Mao, Lanqun

    2013-08-28

    Accurately characterizing the product of photodecomposition of ferrocene derivatives remains a longstanding challenge due to its structural complexity and strong dependence on the solvent and the substituent. Herein, photodecomposition of ferrocenedicarboxylic acid (FcDC) in methanol is found for the first time to form an electroactive infinite coordinate polymer (ICP) with uniform size, good water stability and photostability, and excellent electrochemical activity. The possible mechanism for the ICP formation is proposed based on the fission of the Fe-ring bond and deprotonation of FcDC under light irradiation. The dissociated Fe(2+) is first oxidized to Fe(3+) that consequently coordinates with the deprotonated ferrocene dicarboxylate to produce ICP nanoparticles. This work not only provides a new insight into the product formation of the photodecomposition of ferrocene derivatives but also offers a mild and simple route to the synthesis of electroactive ICPs. PMID:23869481

  15. Hydrothermal synthesis, crystal structure, and catalytic potential of a one-dimensional molybdenum oxide/bipyridinedicarboxylate hybrid.

    PubMed

    Amarante, Tatiana R; Neves, Patrícia; Valente, Anabela A; Paz, Filipe A Almeida; Fitch, Andrew N; Pillinger, Martyn; Gonçalves, Isabel S

    2013-04-15

    The reaction of MoO3, 2,2'-bipyridine-5,5-dicarboxylic acid (H2bpdc), water, and dimethylformamide in the mole ratio 1:1:1730:130 at 150 °C for 3 days in a rotating Teflon-lined digestion bomb leads to the isolation of the molybdenum oxide/bipyridinedicarboxylate hybrid material (DMA)[MoO3(Hbpdc)]·nH2O (1) (DMA = dimethylammonium). Compound 1 was characterized by scanning electron microscopy, FT-IR and (13)C{(1)H} CP MAS NMR spectroscopies, and elemental and thermogravimetric analyses. The solid state structure of 1 was solved and refined through Rietveld analysis of high resolution synchrotron X-ray powder diffraction data in conjunction with information derived from the above techniques. The material, crystallizing in the noncentrosymmetric monoclinic space group Pc, is composed of an anionic one-dimensional organic-inorganic hybrid polymer, ?(1)[MoO3(Hbpdc)](-), formed by corner-sharing distorted {MoO4N2} octahedra, which cocrystallizes with charge-balancing DMA(+) cations and one water molecule per metal center. In the crystal structure of 1, the close packing of individual anionic polymers, DMA(+) cations, and water molecules is mediated by a series of supramolecular contacts, namely strong (O-H···O, N(+)-H···O(-)) and weak (C-H···O) hydrogen bonding interactions, and ?-? contacts involving adjacent coordinated Hbpdc(-) ligands. The catalytic potential of 1 was investigated in the epoxidation reactions of the bioderived olefins methyl oleate (Ole) and DL-limonene (Lim) using tert-butylhydroperoxide (TBHP) as the oxygen donor and 1,2-dichloroethane (DCE) or (trifluoromethyl)benzene (BTF) as cosolvent, at 55 or 75 °C. Under these conditions, 1 acts as a source of active soluble species, leading to epoxide yields of up to 98% for methyl 9,10-epoxystearate (BTF, 75 °C, 100% conversion of Ole) and 89% for 1,2-epoxy-p-menth-8-ene (DCE, 55 °C, 95% conversion of Lim). Catalytic systems employing the ionic liquid 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide as solvent could be effectively recycled. PMID:23531277

  16. Unsteady features on one-dimensional hydrogen-air detonations

    NASA Astrophysics Data System (ADS)

    Daimon, Yu; Matsuo, Akiko

    2007-11-01

    The features of one-dimensional unsteady detonations are studied numerically using a hydrogen-air detailed chemical reaction model. A series of simulations are carried out while degree of overdrive, initial pressure, initial temperature, and equivalence ratio are varied. The oscillation modes and mechanisms of the one-dimensional detonations are discussed with reference to shock pressure histories and x-t diagrams of density distributions. As the degree of overdrive is reduced with a stoichiometric mixture of hydrogen-air at P0=0.421atm and T0=293K, a steady state appears, along with a high-frequency mode and a low-frequency mode. The oscillation mechanism of the high-frequency mode is the same as that of the regular regime of unsteady shock-induced combustion observed around a spherical projectile flying at hypersonic velocity in detonable gases. The degree of overdrive threshold between the steady and unsteady region increases monotonically with initial pressure and decreases monotonically with initial temperature. When the equivalence ratio is changed, the threshold has a minimum value around ? =1. We focus attention on a nondimensional effective activation energy, which is generally used for linear stability analysis. The oscillation mode depends highly on the nondimensional effective activation energy. The oscillation of the detonation front appears as the nondimensional effective activation energy goes past a threshold value of 5.2. Furthermore, we investigate the failed regime and possible reignition in this regime. In the failed regime, a detonation wave breaks up into a leading shock, a contact discontinuity, and a rarefaction wave. When the shock is weak, reignition time becomes very long. Therefore, the reignition after the failed regime is difficult to reproduce in the restricted computational domain. The reignition process in the failed regime is investigated by means of analysis consisting of integration along the point of intersection between a Rayleigh line for weak leading shock and a partially burnt Hugoniot curve. The reignition time increases dramatically with decreasing temperature behind the shock wave, when the gas condition goes past the second explosion limit. The second explosion limit is one of the characteristics of the hydrogen-air detailed chemical reaction model and does not exist in the one-step chemical reaction model. Lastly, the reignition time obtained by the analysis is compared with that obtained by the simulation results. The simulation results agree well with the analytical results.

  17. An adaptive grid algorithm for one-dimensional nonlinear equations

    NASA Technical Reports Server (NTRS)

    Gutierrez, William E.; Hills, Richard G.

    1990-01-01

    Richards' equation, which models the flow of liquid through unsaturated porous media, is highly nonlinear and difficult to solve. Step gradients in the field variables require the use of fine grids and small time step sizes. The numerical instabilities caused by the nonlinearities often require the use of iterative methods such as Picard or Newton interation. These difficulties result in large CPU requirements in solving Richards equation. With this in mind, adaptive and multigrid methods are investigated for use with nonlinear equations such as Richards' equation. Attention is focused on one-dimensional transient problems. To investigate the use of multigrid and adaptive grid methods, a series of problems are studied. First, a multigrid program is developed and used to solve an ordinary differential equation, demonstrating the efficiency with which low and high frequency errors are smoothed out. The multigrid algorithm and an adaptive grid algorithm is used to solve one-dimensional transient partial differential equations, such as the diffusive and convective-diffusion equations. The performance of these programs are compared to that of the Gauss-Seidel and tridiagonal methods. The adaptive and multigrid schemes outperformed the Gauss-Seidel algorithm, but were not as fast as the tridiagonal method. The adaptive grid scheme solved the problems slightly faster than the multigrid method. To solve nonlinear problems, Picard iterations are introduced into the adaptive grid and tridiagonal methods. Burgers' equation is used as a test problem for the two algorithms. Both methods obtain solutions of comparable accuracy for similar time increments. For the Burgers' equation, the adaptive grid method finds the solution approximately three times faster than the tridiagonal method. Finally, both schemes are used to solve the water content formulation of the Richards' equation. For this problem, the adaptive grid method obtains a more accurate solution in fewer work units and less computation time than required by the tridiagonal method. The performance of the adaptive grid method tends to degrade as the solution process proceeds in time, but still remains faster than the tridiagonal scheme.

  18. Statistical properties of chaos demonstrated in a class of one-dimensional maps

    NASA Astrophysics Data System (ADS)

    Csordás, András; Györgyi, Géza; Szépfalusy, Péter; Tél, Tamás

    1993-01-01

    One-dimensional maps with complete grammar are investigated in both permanent and transient chaotic cases. The discussion focuses on statistical characteristics such as Lyapunov exponent, generalized entropies and dimensions, free energies, and their finite size corrections. Our approach is based on the eigenvalue problem of generalized Frobenius-Perron operators, which are treated numerically as well as by perturbative and other analytical methods. The examples include the universal chaos function relevant near the period doubling threshold. Special emphasis is put on the entropies and their decay rates because of their invariance under the most general class of coordinate changes. Phase-transition-like phenomena at the border state of chaos due to intermittency and super instability are presented.

  19. Entanglement Properties of the Two-Electron Quasi-One Dimensional Gaussian Quantum Dot

    NASA Astrophysics Data System (ADS)

    Kuro?, Arkadiusz; Okopi?ska, Anna

    2015-12-01

    We analyze the entanglement characteristics of the quasi one-dimensional quantum dot containing two Coulombically interacting electrons in an inverted Gaussian potential. The linear entropy of the lowest energy states is calculated in the whole range of the effective interaction strength g for different parameters of the longitudinal potential and the lateral radius of the quantum dot. We employ the configuration interaction method with complex-coordinate rotation, since the considered states become autoionizing resonances at the interaction strength above the critical value g th . We study the dependence of the linear entropy on the parameters of the quantum dot and discuss how the stability properties of the system are characterized by the entanglement between the electrons.

  20. Crystal structure of a new homochiral one-dimensional zincophosphate containing l-me­thio­nine

    PubMed Central

    Chouat, Nadjet; Hasnaoui, Mohammed Abdelkrim; Sassi, Mohamed; Bengueddach, Abdelkader; Lusvardi, Gigliola; Cornia, Andrea

    2015-01-01

    catena-Poly[[(l-me­thio­nine-?O)zinc]-?3-(hydrogen phosphato)-?3 O:O?:O??], [Zn{PO3(OH)}(C5H11NO2S)]n, a new one-dimensional homochiral zincophos­phate, was hydro­thermally synthesized using l-me­thio­nine as a structure-directing agent. The compound consists of a network of ZnO4 and (HO)PO3 tetra­hedra that form ladder-like chains of edge-fused Zn2P2O4 rings propagating parallel to [100]. The chains are decorated on each side by zwitterionic l-me­thio­nine ligands, which inter­act with the inorganic framework via Zn—O coordination bonds. The structure displays inter­chain N—H?O and O—H?S hydrogen bonds. PMID:26279879

  1. Moment-Preserving SN Discretizations for the One-Dimensional Fokker-Planck Equation

    SciTech Connect

    Warsa, James S.; Prinja, Anil K.

    2012-06-14

    The Fokker-Planck equation: (1) Describes the transport and interactions of charged particles, (2) Many small-angle scattering collisions, (3) Asymptotic limit of the Boltzmann equation (Pomraning, 1992), and (4) The Boltzmann collision operator becomes the angular Laplacian. SN angular discretization: (1) Angular flux is collocated at the SN quadrature points, (2) The second-order derivatives in the Laplacian term must be discretized, and (3) Weighted finite-difference method preserves zeroth and first moments (Morel, 1985). Moment-preserving methods: (1) Collocate the Fokker-Planck operator at the SN quadrature points, (2) Develop several related and/or equivalent methods, and (3) Motivated by discretizations for the angular derivative appearing in the transport equation in one-dimensional spherical coordinates.

  2. One-dimensional extended defects in epitaxial graphene with metallic properties

    NASA Astrophysics Data System (ADS)

    Lahiri, Jayeeta; Lin, You; Bozkurt, Pinar; Oleynik, Ivan; Batzill, Matthias

    2010-03-01

    Extended one dimensional line defects with metallic electronic properties are described. These defects have been formed in epitaxial graphene on Ni(111) surfaces and are the consequence of domain boundaries between graphene-sheets occupying different registry relative to the nickel substrate. The domain boundary forms a reconstructed line defect with a repeat unit of one octagon and a pair of pentagons. All the atoms in the defect are sp^2 hybridized three-fold coordinated carbon and thus do not exhibit any dangling bonds. DFT calculations indicate that these defect lines exhibit similar flat band states at the Fermi-level as zigzag-edge states in nanoribbons. STM-imaging indicates a bright contrast surrounding these defects, which we attribute to the decaying wave function of the defect states and its associated self-doping effect in the surrounding graphene sheet. This makes this extended defect a metallic wire embedded in a perfect graphene lattice.

  3. Systematic Investigation of Reaction-Time Dependence of Three Series of Copper-Lanthanide/Lanthanide Coordination Polymers: Syntheses, Structures, Photoluminescence, and Magnetism.

    PubMed

    Zhang, Ju-Wen; Kan, Xiao-Min; Liu, Bin-Qiu; Liu, Guo-Cheng; Tian, Ai-Xiang; Wang, Xiu-Li

    2015-11-01

    Three series of copper-lanthanide/lanthanide coordination polymers (CPs) Ln(III) Cu(II) Cu(I) (bct)3 (H2 O)2 [Ln=La (1), Ce (2), Pr (3), Nd (4), Sm (5), Eu (6), Gd (7), Tb (8), Dy (9), Er (10), Yb (11), and Lu (12), H2 bct=2,5-bis(carboxymethylmercapto)-1,3,4-thiadiazole acid], Ln(III) Cu(I) (bct)2 [Ln=Ce (2?a), Pr (3?a), Nd (4?a), Sm (5?a), Eu (6?a), Gd (7?a), Tb (8?a), Dy (9?a), Er (10?a), Yb (11?a), and Lu (12?a)], and Ln(III) 2 (bct)3 (H2 O)5 [Ln=La (1?b), Ce (2?b), Pr (3?b), Nd (4?b), Sm (5?b), Eu (6?b), Gd (7?b), Tb (8?b), and Dy (9?b)] have been successfully constructed under hydrothermal conditions by modulating the reaction time. Structural characterization has revealed that CPs 1-12 possess a unique one-dimensional (1D) strip-shaped structure containing two types of double-helical chains and a double-helical channel. CPs 2?a-12?a show a three-dimensional (3D) framework formed by Cu(I) linking two types of homochiral layers with double-helical channels. CPs 1?b-9?b exhibit a 3D framework with single-helical channels. CPs 6?b and 8?b display visible red and green luminescence of the Eu(III) and Tb(III) ions, respectively, sensitized by the bct ligand, and microsecond-level lifetimes. CP 8?b shows a rare magnetic transition between short-range ferromagnetic ordering at 110?K and long-range ferromagnetic ordering below 10?K. CPs 9?a and 9?b display field-induced single-chain magnet (SCM) and/or single-molecule magnet (SMM) behaviors, with Ueff values of 51.7 and 36.5?K, respectively. PMID:26387571

  4. Rare configuration of tautomeric benzimidazolecarboxylate ligands in cadmium(II) and copper(II) coordination polymers

    SciTech Connect

    Wu, Jing-Yun; Yang, Ciao-Wei; Chen, Hui-Fang; Jao, Yu-Chen; Huang, Sheng-Ming; Tsai, Chiitang; Tseng, Tien-Wen; Lee, Gene-Hsiang; Peng, Shie-Ming; Lu, Kuang-Lieh

    2011-07-15

    Two Cd(HBimc)-based isomers, [Cd(HBimc{sup N})(HBimc{sup T})(H{sub 2}O)].3.5H{sub 2}O.EtOH (1a.3.5H{sub 2}O.EtOH, H{sub 2}Bimc=1H-benzimidazole-5-carboxylic acid) and [Cd(HBimc{sup N})(HBimc{sup T})(H{sub 2}O)] (1b), and two Cu(HMBimc)-based coordination polymers, [Cu(HMBimc{sup N}){sub 2}(H{sub 2}O)].1/2H{sub 2}O (2.1/2H{sub 2}O, H{sub 2}MBimc=2-methyl-1H-benzimidazole-5-carboxylic acid) and [Cu(HMBimc{sup T}){sub 2}].2THF.H{sub 2}O (3.2THF.H{sub 2}O), were self-assembled from Cd(ClO{sub 4}){sub 2}.6H{sub 2}O/H{sub 2}Bimc and Cu(ClO{sub 4}){sub 2}.6H{sub 2}O/H{sub 2}MBimc systems, respectively. Compound 1a adopts a ladder-like chain structure, comprised of a hydrogen-bond-stabilized Cd{sub 2}(HBimc{sup N}){sub 2}-metallocyclic stair and a 1D straight -(Cd-HBimc{sup T}){sub n}- edge, whereas compound 1b exhibits a 2D (4,4)-rhombus layered structure, intercrossed by 1D -(Cd-HBimc{sup N}){sub n}- chains and -(Cd-HBimc{sup T}){sub n}- chains. Compound 2 shows a 1D double-stranded wave-like chain from two single-stranded wave-like -(Cu-HMBimc{sup N}){sub n}- chains and compound 3 adopts a 2D (4,4)-topological layer structure, intercrossed by subunits of 1D -(Cu-HMBimc{sup T}){sub n}- chains. Interestingly, a pair of tautomeric HBimc building blocks-normal (N or HBimc{sup N}) and tautomer (T or HBimc{sup T})-is simultaneously included in the structures of 1a and 1b, whilst the N- and T-configured HMBimc building blocks are present as separate entities in Cu species, 2 and 3, respectively. The existence of only a tautomer (T) mode of the benzimidazolecarboxylate-based ligand in a Cu(II) network is observed for the first time. - Graphical abstract: A pair of tautomeric HBimc building blocks (normal (N) and tautomer (T)) is found simultaneously in two Cd(II) networks, whereas, the normal and tautomer modes of HMBimc are present as separate entities in two Cu(II) frameworks. The isolation of a Cu(II) network with only a tautomer (T) mode of the benzimidazolecarboxylate-based ligand is achieved for the first time. Highlights: {yields}Benzimidazolecarboxylates could exhibit normal (N) and tautomer (T) configurations. > A pair of N- and T-modes of HBimc is found simultaneously in two Cd(II) networks. > The N- and T-modes of HMBimc are separately present in two Cu(II) frameworks. > Only a T mode of HMBimc that existed in the structure is observed for the first time.

  5. A two-dimensional ?–d conjugated coordination polymer with extremely high electrical conductivity and ambipolar transport behaviour

    PubMed Central

    Huang, Xing; Sheng, Peng; Tu, Zeyi; Zhang, Fengjiao; Wang, Junhua; Geng, Hua; Zou, Ye; Di, Chong-an; Yi, Yuanping; Sun, Yimeng; Xu, Wei; Zhu, Daoben

    2015-01-01

    Currently, studies on organic two-dimensional (2D) materials with special optic-electronic properties are attracting great research interest. However, 2D organic systems possessing promising electrical transport properties are still rare. Here a highly crystalline thin film of a copper coordination polymer, Cu-BHT (BHT=benzenehexathiol), is prepared via a liquid–liquid interface reaction between BHT/dichloromethane and copper(II) nitrate/H2O. The morphology and structure characterization reveal that this film is piled up by nanosheets of 2D lattice of [Cu3(C6S6)]n, which is further verified by quantum simulation. Four-probe measurements show that the room temperature conductivity of this material can reach up to 1,580?S?cm?1, which is the highest value ever reported for coordination polymers. Meanwhile, it displays ambipolar charge transport behaviour and extremely high electron and hole mobilities (99?cm2?V?1?s?1 for holes and 116?cm2?V?1?s?1 for electrons) under field-effect modulation. PMID:26074272

  6. Effect of substituent on dimensionality and properties in divalent metal isophthalate coordination polymers with a conformationally flexible dipyridylamide coligand

    NASA Astrophysics Data System (ADS)

    Torres Salgado, Maria D.; LaDuca, Robert L.

    2015-01-01

    Hydrothermal reaction of divalent metal nitrates and 3-pyridylmethylnicotinamide (3-pmna) with either isophthalic acid (H2iph) or 5-nitroisophthalic acid (H2nip) has afforded a series of four coordination polymer solids that were structurally characterized via single-crystal X-ray crystallography. [Ni(iph)(3-pmna)]n (1) and [Cd(iph)(3-pmna)]n (2) both exhibit a {M2(OCO)2} dimer-based 1-D ribbon topology with metal-metal contacts bridged by both ip and 3-pmna ligands. [Ni(nip)(3-pmna)]n (3) has the same topology as its unsubstituted congener 1, showing a null effect on the part of the nip nitro group. On the other hand [Cd(nip)(3-pmna)]n (4) exhibits a {Cd2O2} dimer-based 2-D (4,4) layer topology, a rare example of the nitro group imposing a higher dimensionality in the resulting coordination polymer. While 2 showed strong blue-violet luminescence, quenching mechanisms due to the nitro group rendered 4 non-luminescent. Thermal properties of these new materials are also investigated.

  7. A two-dimensional ?-d conjugated coordination polymer with extremely high electrical conductivity and ambipolar transport behaviour.

    PubMed

    Huang, Xing; Sheng, Peng; Tu, Zeyi; Zhang, Fengjiao; Wang, Junhua; Geng, Hua; Zou, Ye; Di, Chong-an; Yi, Yuanping; Sun, Yimeng; Xu, Wei; Zhu, Daoben

    2015-01-01

    Currently, studies on organic two-dimensional (2D) materials with special optic-electronic properties are attracting great research interest. However, 2D organic systems possessing promising electrical transport properties are still rare. Here a highly crystalline thin film of a copper coordination polymer, Cu-BHT (BHT=benzenehexathiol), is prepared via a liquid-liquid interface reaction between BHT/dichloromethane and copper(II) nitrate/H2O. The morphology and structure characterization reveal that this film is piled up by nanosheets of 2D lattice of [Cu3(C6S6)]n, which is further verified by quantum simulation. Four-probe measurements show that the room temperature conductivity of this material can reach up to 1,580?S?cm(-1), which is the highest value ever reported for coordination polymers. Meanwhile, it displays ambipolar charge transport behaviour and extremely high electron and hole mobilities (99?cm(2?)V(-1?)s(-1) for holes and 116?cm(2?)V(-1?)s(-1) for electrons) under field-effect modulation. PMID:26074272

  8. Influence of photoinduced electron transfer on lanthanide-based coordination polymer luminescence: a comparison between two pseudoisoreticular molecular networks.

    PubMed

    Freslon, Stéphane; Luo, Yun; Calvez, Guillaume; Daiguebonne, Carole; Guillou, Olivier; Bernot, Kevin; Michel, Vincent; Fan, Xiao

    2014-01-21

    The luminescent properties of two families of heteronuclear lanthanide-containing coordination polymers are compared. These families have general chemical formulas [Ln2-2xLn'2x(ip)3(H2O)9·6H2O]? and [Ln2-2xLn'2x(aip)2(H2O)10·(aip)·4H2O]? where H2ip and H2aip stand for isophthalic acid and 5-amino-isophthalic acid, respectively, and where Ln and Ln' are one of the lanthanide ions between Sm(3+) and Dy(3+). Heteronuclear compounds that belong to each family are isostructural to the already reported homonuclear compounds [Gd2(ip)3(H2O)9·6H2O]? and [Eu2(aip)2(H2O)10·(aip)·4H2O]?, respectively. These two crystal structures are very similar. However, despite similar chemical formulas, similar crystal structures, and similar hydration rates, these two families of compounds present very different luminescent properties that have thus been deeply investigated. This study demonstrates that these different optical behaviors can be attributed to the presence of a PET (photoinduced electron transfer) mechanism that is only present in the amino-isophthalate-containing coordination polymers. PMID:24400864

  9. A two-dimensional ?-d conjugated coordination polymer with extremely high electrical conductivity and ambipolar transport behaviour

    NASA Astrophysics Data System (ADS)

    Huang, Xing; Sheng, Peng; Tu, Zeyi; Zhang, Fengjiao; Wang, Junhua; Geng, Hua; Zou, Ye; di, Chong-An; Yi, Yuanping; Sun, Yimeng; Xu, Wei; Zhu, Daoben

    2015-06-01

    Currently, studies on organic two-dimensional (2D) materials with special optic-electronic properties are attracting great research interest. However, 2D organic systems possessing promising electrical transport properties are still rare. Here a highly crystalline thin film of a copper coordination polymer, Cu-BHT (BHT=benzenehexathiol), is prepared via a liquid-liquid interface reaction between BHT/dichloromethane and copper(II) nitrate/H2O. The morphology and structure characterization reveal that this film is piled up by nanosheets of 2D lattice of [Cu3(C6S6)]n, which is further verified by quantum simulation. Four-probe measurements show that the room temperature conductivity of this material can reach up to 1,580 S cm-1, which is the highest value ever reported for coordination polymers. Meanwhile, it displays ambipolar charge transport behaviour and extremely high electron and hole mobilities (99 cm2 V-1 s-1 for holes and 116 cm2 V-1 s-1 for electrons) under field-effect modulation.

  10. Redox-active porous coordination polymer based on trinuclear pivalate: Temperature-dependent crystal rearrangement and redox-behavior

    NASA Astrophysics Data System (ADS)

    Lytvynenko, Anton S.; Kiskin, Mikhail A.; Dorofeeva, Victoria N.; Mishura, Andrey M.; Titov, Vladimir E.; Kolotilov, Sergey V.; Eremenko, Igor L.; Novotortsev, Vladimir M.

    2015-03-01

    Linking of trinuclear pivalate Fe2NiO(Piv)6 (Piv=O2CC(CH3)3) by 2,6-bis(4-pyridyl)-4-(1-naphthyl)pyridine (L) resulted in formation of 1D-porous coordination polymer Fe2NiO(Piv)6(L)·Solv, which was characterized in two forms: DMSO solvate Fe2NiO(Piv)6(L)(DMSO)·2.5DMSO (1) or water solvate Fe2NiO(Piv)6(L)(H2O) (2). X-ray structure of 1 was determined. Crystal lattice of 1 at 160 K contained open channels, filled by captured solvent, while temperature growth to 296 K led to the crystal lattice rearrangement and formation of closed voids. Redox-behavior of 2 was studied by cyclic voltammetry for a solid compound, deposited on glassy-carbon electrode. Redox-activity of L preserved upon incorporation in the coordination polymer. The presence of pores in desolvated sample Fe2NiO(Piv)6(L) was confirmed by the measurements of N2 and H2 adsorption at 77 K. Potential barriers of the different molecules diffusion through pores were estimated by the means of molecular mechanics.

  11. Conductance distribution in quasi-one-dimensional disordered quantum wires

    NASA Astrophysics Data System (ADS)

    Muttalib, K. A.; Wölfle, P.; Gopar, V. A.

    2003-11-01

    We develop a simple systematic method, valid for all strengths of disorder, to obtain analytically the full distribution of conductances P( g) for a quasi-one-dimensional wire within the model of non-interacting fermions. The method has been used in [Phys. Rev. Lett. 83 (1999) 3013; Ann. Phys. (Leipzig) 8 (1999) 753; Phys. Rev. B 66 (2002) 174204; Europhys. Lett. 61 (2003) 95] to predict sharp features in P( g) near g=1 and the existence of non-analyticity in the conductance distribution in the insulating and crossover regimes, as well as to show how P( g) changes from Gaussian to log-normal behavior as the disorder strength is increased. Here we provide many details of the method, including intermediate results that offer much insight into the nature of the solutions. In addition, we show within the same framework that while for metals P( g) is a Gaussian around < g>?1, there exists a log-normal tail for g?1, consistent with earlier field theory calculations. We also obtain several other results that compare very well with available exact results in the metallic and insulating regimes.

  12. Drag dynamics in one-dimensional Fermi systems

    E-print Network

    Jun'ichi Ozaki; Masaki Tezuka; Norio Kawakami

    2015-07-29

    We study drag dynamics of several fermions in a fermion cloud in one-dimensional continuous systems, with particular emphasis on the non-trivial quantum many-body effects in systems whose parameters change gradually in real time. We adopt the Fermi--Hubbard model and the time-dependent density matrix renormalization group method to calculate the drag force on a trapped fermion cluster in a cloud of another fermion species with contact interaction. The simulation result shows that a non-trivial peak in the resistance force is observed in the high cloud density region, which implies a criterion of effective ways in diffusive transport in a fermion cloud. We compare the DMRG simulation result with a mean-field result, and it is suggested that some internal degrees of freedom have a crucial role in the excitation process when the cloud density is high. This work emphasizes the difference between the full-quantum calculation and the semiclassical calculation, which is the quantum effects, in slow dynamics of many-body systems bound in a fermion cloud.

  13. Reaction, trapping, and multifractality in one-dimensional systems

    SciTech Connect

    Broeck, C. Van den )

    1991-12-01

    The first part of this paper presents two variants of the A + A {yields} A and A + A {yields} P reaction in one dimension that can be investigated analytically. In the first model, pairs of neighboring particles disappear reactively at a rate which is independent of their relative distance. It is shown that the probability density {var phi}(x) for a nearest neighbor distance equal to x approaches the scaling form {var phi}(x) {approximately} c exp({minus} cx/2)/(cs){sup 1/2} in the long-time limit, with c being the concentration of particles. The second model is a ballistic analogue of the coagulation reaction A + A {yields} A. The model is solved by reducing it to a first-passage-time problem. The anomalous relaxation dynamics can be linked in a direct way to the fractal time properties of random walks. The second part of this paper discusses the complications that arise in systems with disorder. A new approach is presented that relates first-passage-time characteristics in a one-dimensional random walk to properties of random maps. In particular, it is shown that Sinai disorder is a borderline case for the appearance of multifractal properties. Finally, a previously introduced renormalization technique is applied to calculate the survival probability of particles moving on the line in the presence of a background of imperfect traps.

  14. Fractal geometry in an expanding, one-dimensional, Newtonian universe.

    PubMed

    Miller, Bruce N; Rouet, Jean-Louis; Le Guirriec, Emmanuel

    2007-09-01

    Observations of galaxies over large distances reveal the possibility of a fractal distribution of their positions. The source of fractal behavior is the lack of a length scale in the two body gravitational interaction. However, even with new, larger, sample sizes from recent surveys, it is difficult to extract information concerning fractal properties with confidence. Similarly, three-dimensional N-body simulations with a billion particles only provide a thousand particles per dimension, far too small for accurate conclusions. With one-dimensional models these limitations can be overcome by carrying out simulations with on the order of a quarter of a million particles without compromising the computation of the gravitational force. Here the multifractal properties of two of these models that incorporate different features of the dynamical equations governing the evolution of a matter dominated universe are compared. For each model at least two scaling regions are identified. By employing criteria from dynamical systems theory it is shown that only one of them can be geometrically significant. The results share important similarities with galaxy observations, such as hierarchical clustering and apparent bifractal geometry. They also provide insights concerning possible constraints on length and time scales for fractal structure. They clearly demonstrate that fractal geometry evolves in the mu (position, velocity) space. The observed patterns are simply a shadow (projection) of higher-dimensional structure. PMID:17930359

  15. Gravitational force in an infinite one-dimensional Poisson distribution.

    PubMed

    Gabrielli, A; Joyce, M

    2010-02-01

    We consider the statistical properties of the gravitational field F in an infinite one-dimensional homogeneous Poisson distribution of particles using an exponential cutoff of the pair interaction to control and study the divergences which arise. Deriving an exact analytic expression for the probability density function (PDF) P(F) , we show that it is badly defined in the limit in which the well-known Holtzmark distribution is obtained in the analogous three-dimensional case. A well-defined P(F) may, however, be obtained in the infinite range limit by an appropriate renormalization of the coupling strength giving a Gaussian form. Calculating the spatial correlation properties we show that this latter procedure has a trivial physical meaning. Finally we calculate the PDF and correlation properties of differences of forces (at separate spatial points), which are well defined without any renormalization. We explain that the convergence of these quantities is in fact sufficient to allow a physically meaningful infinite system limit to be defined for the clustering dynamics from Poissonian initial conditions. PMID:20365525

  16. One-dimensional quantum walk with a moving boundary

    SciTech Connect

    Kwek, Leong Chuan; Setiawan

    2011-09-15

    Quantum walks are interesting models with potential applications to quantum algorithms and physical processes such as photosynthesis. In this paper, we study two models of one-dimensional quantum walks, namely, quantum walks with a moving absorbing wall and quantum walks with one stationary and one moving absorbing wall. For the former, we calculate numerically the survival probability, the rate of change of average position, and the rate of change of standard deviation of the particle's position in the long time limit for different wall velocities. Moreover, we also study the asymptotic behavior and the dependence of the survival probability on the initial particle's state. While for the latter, we compute the absorption probability of the right stationary wall for different velocities and initial positions of the left wall boundary. The results for these two models are compared with those obtained for the classical model. The difference between the results obtained for the quantum and classical models can be attributed to the difference in the probability distributions.

  17. Interspecies tunneling in one-dimensional Bose mixtures

    SciTech Connect

    Pflanzer, Anika C.; Zoellner, Sascha; Schmelcher, Peter

    2010-02-15

    We study the ground-state properties and quantum dynamics of few-boson mixtures with strong interspecies repulsion in one-dimensional traps. If one species localizes at the center, e.g., due to a very large mass compared to the other component, it represents an effective barrier for the latter, and the system can be mapped onto identical bosons in a double well. For weaker localization, the barrier atoms begin to respond to the light component, leading to an induced attraction between the mobile atoms that may even outweigh their bare intraspecies repulsion. To explain the resulting effects, we derive an effective Hubbard model for the lighter species accounting for the back action of the barrier in correction terms to the lattice parameters. Also the tunneling is drastically affected: by varying the degree of localization of the 'barrier' atoms, the dynamics of intrinsically noninteracting bosons can change from Rabi oscillations to effective pair tunneling. For identical fermions (or fermionized bosons), this leads to the tunneling of attractively bound pairs.

  18. Fractal spectra in generalized Fibonacci one-dimensional magnonic quasicrystals

    NASA Astrophysics Data System (ADS)

    Costa, C. H. O.; Vasconcelos, M. S.; Barbosa, P. H. R.; Barbosa Filho, F. F.

    2012-07-01

    In this work we carry out a theoretical analysis of the spectra of magnons in quasiperiodic magnonic crystals arranged in accordance with generalized Fibonacci sequences in the exchange regime, by using a model based on a transfer-matrix method together random-phase approximation (RPA). The generalized Fibonacci sequences are characterized by an irrational parameter ?(p,q), which rules the physical properties of the system. We discussed the magnonic fractal spectra for first three generalizations, i.e., silver, bronze and nickel mean. By varying the generation number, we have found that the fragmentation process of allowed bands makes possible the emergence of new allowed magnonic bulk bands in spectra regions that were magnonic band gaps before, such as which occurs in doped semiconductor devices. This interesting property arises in one-dimensional magnonic quasicrystals fabricated in accordance to quasiperiodic sequences, without the need to introduce some deferent atomic layer or defect in the system. We also make a qualitative and quantitative investigations on these magnonic spectra by analyzing the distribution and magnitude of allowed bulk bands in function of the generalized Fibonacci number Fn and as well as how they scale as a function of the number of generations of the sequences, respectively.

  19. A Smart Colorful Supercapacitor with One Dimensional Photonic Crystals.

    PubMed

    Liu, Cihui; Liu, Xing; Xuan, Hongyun; Ren, Jiaoyu; Ge, Liqin

    2015-01-01

    To meet the pressing demands for portable and flexible equipment in contemporary society, developing flexible, lightweight, and sustainable supercapacitor systems with large power densities, long cycle life, and ease of strongly required. However, estimating the state-of-charge of existing supercapacitors is difficult, and thus their service life is limited. In this study, we fabricate a flexible color indicative supercapacitor device with mesoporous polyaniline (mPANI)/Poly(N-Isopropyl acrylamide-Graphene Oxide-Acrylic Acid) (P(NiPPAm-GO-AA)) one dimensional photonic crystals (1DPCs) as the electrode material through a low-cost, eco-friendly, and scalable fabrication process. We found that the state-of-charge could be monitored by the structural color oscillation due to the change in the photonic band gap position of the 1DPCs. The flexible 1DPCs supercapacitor is thin at 3?mm and exhibits good specific capacitance of 22.6?F g(-1) with retention of 91.1% after 3,000 cycles. This study shows the application of the 1DPCs supercapacitor as a visual ultrathin power source. The technology may find many applications in future wearable electronics. PMID:26689375

  20. Numerical method of characteristics for one-dimensional blood flow

    NASA Astrophysics Data System (ADS)

    Acosta, Sebastian; Puelz, Charles; Rivière, Béatrice; Penny, Daniel J.; Rusin, Craig G.

    2015-08-01

    Mathematical modeling at the level of the full cardiovascular system requires the numerical approximation of solutions to a one-dimensional nonlinear hyperbolic system describing flow in a single vessel. This model is often simulated by computationally intensive methods like finite elements and discontinuous Galerkin, while some recent applications require more efficient approaches (e.g. for real-time clinical decision support, phenomena occurring over multiple cardiac cycles, iterative solutions to optimization/inverse problems, and uncertainty quantification). Further, the high speed of pressure waves in blood vessels greatly restricts the time step needed for stability in explicit schemes. We address both cost and stability by presenting an efficient and unconditionally stable method for approximating solutions to diagonal nonlinear hyperbolic systems. Theoretical analysis of the algorithm is given along with a comparison of our method to a discontinuous Galerkin implementation. Lastly, we demonstrate the utility of the proposed method by implementing it on small and large arterial networks of vessels whose elastic and geometrical parameters are physiologically relevant.

  1. A one-dimensional model of Nucleosome distribution in DNA

    NASA Astrophysics Data System (ADS)

    Osberg, Brendan; Moebius, Wolfram; Nguyen, Kien; Gerland, Ulrich

    2012-02-01

    Nucleosome positioning along DNA is neither random nor precisely regular. Genome-wide maps of nucleosome positions in various eukaryotes have revealed a common pattern around transcription start sites, involving a nucleosome-free region flanked by a periodic pattern in the average nucleosome density. We take a quantitative mathematical description of the nucleosome pattern, and incorporate specifically bound transcription factors. Our model assumes a dense, one-dimensional gas of particles, however, instead of previous work which assumes fixed-size particles interacting only by exclusion, our model explicitly accounts for transient unwrapping of short segments of nucleosomal DNA. Hence, such particles no longer have a fixed size, but interact by an effective repulsive potential. This model has been succesfully used, by us, to provide a unified description of 12 Hemiascomycota yeast species with a single unified set of model parameters. We incorporate into this model, specifically bound particles, or transcription factors (TF), which serve an important role in gene regulation. Nucleosome distribution patterns have an important influence on TF binding, and can even mediate interactions between transcription factors at a distance. This interaction can account for cooperative or competitive binding between these proteins, and we will discuss the implications this can have on gene regulation.

  2. Bulk-edge correspondence of one-dimensional quantum walks

    E-print Network

    C. Cedzich; F. A. Grünbaum; C. Stahl; L. Velázquez; A. H. Werner; R. F. Werner

    2015-05-19

    We outline a theory of symmetry protected topological phases of one-dimensional quantum walks. We assume spectral gaps around the symmetry-distinguished points +1 and -1, in which only discrete eigenvalues are allowed. The phase classification by integer or binary indices extends the classification known for translation invariant systems in terms of their band structure. However, our theory requires no translation invariance whatsoever, and the indices we define in this general setting are invariant under arbitrary symmetric local perturbations, even those that cannot be continuously contracted to the identity. More precisely we define two indices for every walk, characterizing the behavior far to the right and far to the left, respectively. Their sum is a lower bound on the number of eigenstates at +1 and -1. For a translation invariant system the indices add up to zero, so one of them already characterizes the phase. By joining two bulk phases with different indices we get a walk in which the right and left indices no longer cancel, so the theory predicts bound states at +1 or -1. This is a rigorous statement of bulk-edge correspondence. The results also apply to the Hamiltonian case with a single gap at zero.

  3. Tunneling through one-dimensional piecewise-constant potential barriers

    NASA Astrophysics Data System (ADS)

    Das, Siddhant

    2015-07-01

    In this paper, we examine transmission through one-dimensional potential barriers that are piecewise constant. The transfer matrix approach is adopted, and a new formula is derived for multiplying long matrix sequences that not only leads to an elegant representation of the wave function but also results in much faster computation than earlier methods. The proposed method covers a broad spectrum of potentials, of which multi-barrier systems are special cases. The procedure is illustrated with a finite lattice of nonuniform rectangular barriers—non-uniformity being a novel feature, as the uniform case has been solved exactly by Griffiths and Steinke. For the nonuniform multi-barrier problem, the intervening wells strongly influence the transmission probability. Surprisingly, we find that the wells act "individually," i.e., their influence is a function only of their width and is independent of their exact locations in a multi-barrier system. This finding leads to an observation that we have termed the "alias effect." The exact solutions are supplemented with asymptotic formulas.

  4. Topological order in interacting one-dimensional Bose Systems

    NASA Astrophysics Data System (ADS)

    Grusdt, Fabian; Höning, Michael; Fleischhauer, Michael

    2015-05-01

    We discuss topological aspects of one-dimensional inversion-symmetric systems of interacting bosons, which can be implemented in current experiments with ultra cold atoms. We consider both integer and fractional fillings of a topologically non-trivial Bloch band. Our starting point is the chiral-symmetric Su-Schrieffer-Heeger (SSH) model of non-interacting fermions, which can be realized by hard-core bosons. When the hard-core constraint is removed, we obtain a bosonic system with inversion-symmetry protected topological order. Because the chiral symmetry is broken by finite interactions, the bulk-boundary correspondence of the SSH model is no longer valid. Nevertheless we show that the fractional part of the charge which is localized at the edge can distinguish topologically trivial- from non-trivial states. We generalize our analysis by including nearest neighbor interactions and present a topological classification of the resulting quarter-filling Mott insulating phase. In this case fractionally charged bulk excitations exist, which we identify in the grand-canonical phase diagram. F.G. acknowledges support from the Graduate School of Material Science MAINZ.

  5. One-dimensional nanoferroic rods; synthesis and characterization

    NASA Astrophysics Data System (ADS)

    Ahmed, M. A.; Seddik, U.; Okasha, N.; Imam, N. G.

    2015-11-01

    One-dimensional nanoferroic rods of BaTiO3 were synthesized by improved citrate auto-combustion technology using tetrabutyl titanate. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), transmission electron microscopy (TEM), atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR) have been used to characterize the prepared sample. The results indicated that the crystal structure of BaTiO3 is tetragonal phase with an average crystallite size of 47 nm. SEM image gives a cauliflower-like morphology of the agglomerated nanorods. The stoichiometry of the chemical composition of the BaTiO3 ceramic was confirmed by EDX. TEM micrograph exhibited that BaTiO3 nanoparticles have rod-like shape with an average length of 120 nm and width of 43 nm. AFM was used to investigate the surface topography and its roughness. The topography image in 3D showed that the BaTiO3 particles have a rod shape with an average particle size of 116 nm which in agreement with 3D TEM result.

  6. Approximate approaches to the one-dimensional finite potential well

    NASA Astrophysics Data System (ADS)

    Singh, Shilpi; Pathak, Praveen; Singh, Vijay A.

    2011-11-01

    The one-dimensional finite well is a textbook problem. We propose approximate approaches to obtain the energy levels of the well. The finite well is also encountered in semiconductor heterostructures where the carrier mass inside the well (mi) is taken to be distinct from mass outside (mo). A relevant parameter is the mass discontinuity ratio ? = mi/mo. To correctly account for the mass discontinuity, we apply the BenDaniel-Duke boundary condition. We obtain approximate solutions for two cases: when the well is shallow and when the well is deep. We compare the approximate results with the exact results and find that higher-order approximations are quite robust. For the shallow case, the approximate solution can be expressed in terms of a dimensionless parameter ?l = 2moV0L2/planck2 (or ? = ?2?l for the deep case). We show that the lowest-order results are related by a duality transform. We also discuss how the energy upscales with L (E~1/L?) and obtain the exponent ?. Exponent ? ? 2 when the well is sufficiently deep and ? ? 1. The ratio of the masses dictates the physics. Our presentation is pedagogical and should be useful to students on a first course on elementary quantum mechanics or low-dimensional semiconductors.

  7. Using the NASA GRC Sectored-One-Dimensional Combustor Simulation

    NASA Technical Reports Server (NTRS)

    Paxson, Daniel E.; Mehta, Vishal R.

    2014-01-01

    The document is a user manual for the NASA GRC Sectored-One-Dimensional (S-1-D) Combustor Simulation. It consists of three sections. The first is a very brief outline of the mathematical and numerical background of the code along with a description of the non-dimensional variables on which it operates. The second section describes how to run the code and includes an explanation of the input file. The input file contains the parameters necessary to establish an operating point as well as the associated boundary conditions (i.e. how it is fed and terminated) of a geometrically configured combustor. It also describes the code output. The third section describes the configuration process and utilizes a specific example combustor to do so. Configuration consists of geometrically describing the combustor (section lengths, axial locations, and cross sectional areas) and locating the fuel injection point and flame region. Configuration requires modifying the source code and recompiling. As such, an executable utility is included with the code which will guide the requisite modifications and insure that they are done correctly.

  8. Dynamic response of one-dimensional bosons in a trap

    SciTech Connect

    Golovach, Vitaly N.; Minguzzi, Anna; Glazman, Leonid I.

    2009-10-15

    We calculate the dynamic structure factor S(q,{omega}) of a one-dimensional (1D) interacting Bose gas confined in a harmonic trap. The effective interaction depends on the strength of the confinement enforcing the (1D) motion of atoms; interaction may be further enhanced by superimposing an optical lattice on the trap potential. In the compressible state, we find that the smooth variation in the gas density around the trap center leads to softening of the singular behavior of S(q,{omega}) at the first Lieb excitation mode compared to the behavior predicted for homogeneous 1D systems. Nevertheless, the density-averaged response S(q,{omega}) remains a nonanalytic function of q and {omega} at the first Lieb excitation mode in the limit of weak trap confinement. The exponent of the power-law nonanalyticity is modified due to the inhomogeneity in a universal way and thus bears unambiguously the information about the (homogeneous) Lieb-Liniger model. A strong optical lattice causes formation of Mott phases. Deep in the Mott regime, we predict a semicircular peak in S(q,{omega}) centered at the on-site repulsion energy, {omega}=U. Similar peaks of smaller amplitudes exist at multiples of U as well. We explain the suppression of the dynamic response with entering into the Mott regime, observed recently by Clement et al. [Phys. Rev. Lett. 102, 155301 (2009)], based on an f-sum rule for the Bose-Hubbard model.

  9. One-dimensional flows of an imperfect diatomic gas

    NASA Technical Reports Server (NTRS)

    1959-01-01

    With the assumptions that Berthelot's equation of state accounts for molecular size and intermolecular force effects, and that changes in the vibrational heat capacities are given by a Planck term, expressions are developed for analyzing one-dimensional flows of a diatomic gas. The special cases of flow through normal and oblique shocks in free air at sea level are investigated. It is found that up to a Mach number 10 pressure ratio across a normal shock differs by less than 6 percent from its ideal gas value; whereas at Mach numbers above 4 the temperature rise is considerable below and hence the density rise is well above that predicted assuming ideal gas behavior. It is further shown that only the caloric imperfection in air has an appreciable effect on the pressures developed in the shock process considered. The effects of gaseous imperfections on oblique shock-flows are studied from the standpoint of their influence on the life and pressure drag of a flat plate operating at Mach numbers of 10 and 20. The influence is found to be small. (author)

  10. Validation and Comparison of One-Dimensional Graound Motion Methodologies

    SciTech Connect

    B. Darragh; W. Silva; N. Gregor

    2006-06-28

    Both point- and finite-source stochastic one-dimensional ground motion models, coupled to vertically propagating equivalent-linear shear-wave site response models are validated using an extensive set of strong motion data as part of the Yucca Mountain Project. The validation and comparison exercises are presented entirely in terms of 5% damped pseudo absolute response spectra. The study consists of a quantitative analyses involving modeling nineteen well-recorded earthquakes, M 5.6 to 7.4 at over 600 sites. The sites range in distance from about 1 to about 200 km in the western US (460 km for central-eastern US). In general, this validation demonstrates that the stochastic point- and finite-source models produce accurate predictions of strong ground motions over the range of 0 to 100 km and for magnitudes M 5.0 to 7.4. The stochastic finite-source model appears to be broadband, producing near zero bias from about 0.3 Hz (low frequency limit of the analyses) to the high frequency limit of the data (100 and 25 Hz for response and Fourier amplitude spectra, respectively).

  11. One-dimensional Kac model of dense amorphous hard spheres

    NASA Astrophysics Data System (ADS)

    Ikeda, H.; Ikeda, A.

    2015-08-01

    We introduce a new model of hard spheres under confinement for the study of the glass and jamming transitions. The model is a one-dimensional chain of the d-dimensional boxes each of which contains the same number of hard spheres, and the particles in the boxes of the ends of the chain are quenched at their equilibrium positions. We focus on the infinite-dimensional limit (d \\to ?) of the model and analytically compute the glass transition densities using the replica liquid theory. From the chain length dependence of the transition densities, we extract the characteristic length scales at the glass transition. The divergence of the lengths are characterized by the two exponents, -1/4 for the dynamical transition and -1 for the ideal glass transition, which are consistent with those of the p-spin mean-field spin glass model. We also show that the model is useful for the study of the growing length scale at the jamming transition.

  12. The dynamics of one-dimensional excitons in liquids

    NASA Astrophysics Data System (ADS)

    van Burgel, Mirjam; Wiersma, Douwe A.; Duppen, Koos

    1995-01-01

    The properties of excitons in one-dimensional molecular aggregates, dissolved at room temperature in a liquid, were studied by means of femtosecond nonlinear optical experiments. Both the one-exciton band (i.e., Frenkel-excitons) and multiexciton bands contribute to the observed nonlinear optical response. The rapid motions in the liquid lead to ultrafast perturbations of the molecular energy levels. This localizes the excitons on limited sections of the chains of aggregated molecules. Ultrafast frequency-resolved pump-probe spectroscopy on the lowest two exciton bands was employed to determine the delocalization length of the optical excitations. The kinetics of the exciton populations was measured by ultrafast grating scattering experiments and time-resolved single photon counting. A model is described in which the multiexciton bands act as doorway states in the exciton-exciton annihilation process. These bands thereby determine the population decay of the Frenkel excitons at high excitation densities. Room temperature photon echo experiments show that stochastic perturbations of the exciton transition frequencies occur on two distinct time scales. In particular the slow components of the fluctuations are affected by motional narrowing, associated with the exciton delocalization length. It is therefore argued that the optical dephasing of excitons is directly related to the spatial extent of the excitation on the aggregate chain.

  13. Digital noise generators using one-dimensional chaotic maps

    SciTech Connect

    Martínez-Ñonthe, J. A; Palacios-Luengas, L.; Cruz-Irisson, M.; Vazquez Medina, R.; Díaz Méndez, J. A.

    2014-05-15

    This work shows how to improve the statistical distribution of signals produced by digital noise generators designed with one-dimensional (1-D) chaotic maps. It also shows that in a digital electronic design the piecewise linear chaotic maps (PWLCM) should be considered because they do not have stability islands in its chaotic behavior region, as it occurs in the case of the logistic map, which is commonly used to build noise generators. The design and implementation problems of the digital noise generators are analyzed and a solution is proposed. This solution relates the output of PWLCM, usually defined in the real numbers' domain, with a codebook of S elements, previously defined. The proposed solution scheme produces digital noise signals with a statistical distribution close to a uniform distribution. Finally, this work shows that it is possible to have control over the statistical distribution of the noise signal by selecting the control parameter of the PWLCM and using, as a design criterion, the bifurcation diagram.

  14. Carbyne with finite length: The one-dimensional sp carbon

    PubMed Central

    Pan, Bitao; Xiao, Jun; Li, Jiling; Liu, Pu; Wang, Chengxin; Yang, Guowei

    2015-01-01

    Carbyne is the one-dimensional allotrope of carbon composed of sp-hybridized carbon atoms. Definitive evidence for carbyne has remained elusive despite its synthesis and preparation in the laboratory. Given the remarkable technological breakthroughs offered by other allotropes of carbon, including diamond, graphite, fullerenes, carbon nanotubes, and graphene, interest in carbyne and its unusual potential properties remains intense. We report the first synthesis of carbyne with finite length, which is clearly composed of alternating single bonds and triple bonds, using a novel process involving laser ablation in liquid. Spectroscopic analyses confirm that the product is the structure of sp hybridization with alternating carbon-carbon single bonds and triple bonds and capped by hydrogen. We observe purple-blue fluorescence emissions from the gap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital of carbyne. Condensed-phase carbyne crystals have a hexagonal lattice and resemble the white crystalline powder produced by drying a carbyne solution. We also establish that the combination of gold and alcohol is crucial to carbyne formation because carbon-hydrogen bonds can be cleaved with the help of gold catalysts under the favorable thermodynamic environment provided by laser ablation in liquid and because the unique configuration of two carbon atoms in an alcohol molecule matches the elementary entity of carbyne. This laboratory synthesis of carbyne will enable the exploration of its properties and applications. PMID:26601318

  15. Weak lasing in one-dimensional polariton superlattices

    PubMed Central

    Zhang, Long; Xie, Wei; Wang, Jian; Poddubny, Alexander; Lu, Jian; Wang, Yinglei; Gu, Jie; Liu, Wenhui; Xu, Dan; Shen, Xuechu; Rubo, Yuri G.; Altshuler, Boris L.; Kavokin, Alexey V.; Chen, Zhanghai

    2015-01-01

    Bosons with finite lifetime exhibit condensation and lasing when their influx exceeds the lasing threshold determined by the dissipative losses. In general, different one-particle states decay differently, and the bosons are usually assumed to condense in the state with the longest lifetime. Interaction between the bosons partially neglected by such an assumption can smear the lasing threshold into a threshold domain—a stable lasing many-body state exists within certain intervals of the bosonic influxes. This recently described weak lasing regime is formed by the spontaneously symmetry breaking and phase-locking self-organization of bosonic modes, which results in an essentially many-body state with a stable balance between gains and losses. Here we report, to our knowledge, the first observation of the weak lasing phase in a one-dimensional condensate of exciton–polaritons subject to a periodic potential. Real and reciprocal space photoluminescence images demonstrate that the spatial period of the condensate is twice as large as the period of the underlying periodic potential. These experiments are realized at room temperature in a ZnO microwire deposited on a silicon grating. The period doubling takes place at a critical pumping power, whereas at a lower power polariton emission images have the same periodicity as the grating. PMID:25787253

  16. Weak lasing in one-dimensional polariton superlattices.

    PubMed

    Zhang, Long; Xie, Wei; Wang, Jian; Poddubny, Alexander; Lu, Jian; Wang, Yinglei; Gu, Jie; Liu, Wenhui; Xu, Dan; Shen, Xuechu; Rubo, Yuri G; Altshuler, Boris L; Kavokin, Alexey V; Chen, Zhanghai

    2015-03-31

    Bosons with finite lifetime exhibit condensation and lasing when their influx exceeds the lasing threshold determined by the dissipative losses. In general, different one-particle states decay differently, and the bosons are usually assumed to condense in the state with the longest lifetime. Interaction between the bosons partially neglected by such an assumption can smear the lasing threshold into a threshold domain--a stable lasing many-body state exists within certain intervals of the bosonic influxes. This recently described weak lasing regime is formed by the spontaneously symmetry breaking and phase-locking self-organization of bosonic modes, which results in an essentially many-body state with a stable balance between gains and losses. Here we report, to our knowledge, the first observation of the weak lasing phase in a one-dimensional condensate of exciton-polaritons subject to a periodic potential. Real and reciprocal space photoluminescence images demonstrate that the spatial period of the condensate is twice as large as the period of the underlying periodic potential. These experiments are realized at room temperature in a ZnO microwire deposited on a silicon grating. The period doubling takes place at a critical pumping power, whereas at a lower power polariton emission images have the same periodicity as the grating. PMID:25787253

  17. Analytic Bjorken flow in one-dimensional relativistic magnetohydrodynamics

    NASA Astrophysics Data System (ADS)

    Roy, Victor; Pu, Shi; Rezzolla, Luciano; Rischke, Dirk

    2015-11-01

    In the initial stage of relativistic heavy-ion collisions, strong magnetic fields appear due to the large velocity of the colliding charges. The evolution of these fields appears as a novel and intriguing feature in the fluid-dynamical description of heavy-ion collisions. In this work, we study analytically the one-dimensional, longitudinally boost-invariant motion of an ideal fluid in the presence of a transverse magnetic field. Interestingly, we find that, in the limit of ideal magnetohydrodynamics, i.e., for infinite conductivity, and irrespective of the strength of the initial magnetization, the decay of the fluid energy density e with proper time ? is the same as for the time-honoured "Bjorken flow" without magnetic field. Furthermore, when the magnetic field is assumed to decay ??-a, where a is an arbitrary number, two classes of analytic solutions can be found depending on whether a is larger or smaller than one. In summary, the analytic solutions presented here highlight that the Bjorken flow is far more general than formerly thought. These solutions can serve both to gain insight on the dynamics of heavy-ion collisions in the presence of strong magnetic fields and as testbeds for numerical codes.

  18. Scattering by infinitely rising one-dimensional potentials

    NASA Astrophysics Data System (ADS)

    Ferreira, E. M.; Sesma, J.

    2015-12-01

    Infinitely rising one-dimensional potentials constitute impenetrable barriers which reflect totally any incident wave. However, the scattering by such kind of potentials is not structureless: resonances may occur for certain values of the energy. Here we consider the problem of scattering by the members of a family of potentials Va(x) = - sgn(x) | x | a, where sgn represents the sign function and a is a positive rational number. The scattering function and the phase shifts are obtained from global solutions of the Schrödinger equation. For the determination of the Gamow states, associated to resonances, we exploit their close relation with the eigenvalues of the PT-symmetric Hamiltonians with potentials VaPT(x) = - i sgn(x) | x | a. Calculation of the time delay in the scattering at real energies is used to characterize the resonances. As an additional result, the breakdown of the PT-symmetry of the family of potentials VaPT for a < 3 may be conjectured.

  19. Statistical properties of one-dimensional parametrically kicked Hamilton systems

    NASA Astrophysics Data System (ADS)

    Andresas, Dimitris; Batisti?, Benjamin; Robnik, Marko

    2014-06-01

    We study the one-dimensional Hamiltonian systems and their statistical behavior, assuming the initial microcanonical distribution and describing its change under a parametric kick, which by definition means a discontinuous jump of a control parameter of the system. Following a previous work by Papamikos and Robnik [J. Phys. A: Math. Theor. 44, 315102 (2011), 10.1088/1751-8113/44/31/315102], we specifically analyze the change of the adiabatic invariant (the action) of the system under a parametric kick: A conjecture has been put forward that the change of the action at the mean energy always increases, which means, for the given statistical ensemble, that the Gibbs entropy in the mean increases. By means of a detailed analysis of a great number of case studies, we show that the conjecture largely is satisfied, except if either the potential is not smooth enough or if the energy is too close to a stationary point of the potential (separatrix in the phase space). Very fast changes in a time-dependent system quite generally can be well described by such a picture and by the approximation of a parametric kick, if the change of the parameter is sufficiently fast and takes place on the time scale of less than one oscillation period. We discuss our work in the context of the statistical mechanics in the sense of Gibbs.

  20. Resistance statistics in one-dimensional systems with correlated disorder

    SciTech Connect

    de Oliveira, M.J.; Petri, A.

    1997-07-01

    We address the general problem of computing dc resistance fluctuations in one-dimensional Anderson models with spatially correlated disorder and discuss some examples of binary systems with Markovian correlations. As in the general case of uncorrelated disorder, we observe a growth of the relative resistance fluctuations {l_angle}{rho}{sub N}{sup 2}{r_angle}/{l_angle}{rho}{sub N}{r_angle}{sup 2} with the system length N. The largest sample-to-sample fluctuations are found in certain energy regions of quasipure systems with very low concentrations of defects, whereas constitutional entropy seems to rule the behavior of typical values of the resistance in different regions and no role appears to be played by the potential correlation length. We express the growth of relative fluctuations in terms of the entropy function characterizing different possible localization lengths of the wave function and observe convergence toward a universal lognormal distribution in the presence of an extended state. {copyright} {ital 1997} {ital The American Physical Society}

  1. Decay of spin coherences in one-dimensional spin systems

    E-print Network

    Gurneet Kaur; Ashok Ajoy; Paola Cappellaro

    2013-06-11

    Strategies to protect multi-qubit states against decoherence are difficult to formulate because of their complex many-body dynamics. A better knowledge of the decay dynamics would help in the construction of decoupling control schemes. Here we use solid-state nuclear magnetic resonance techniques to experimentally investigate the decay of coherent multi-spin states in linear spin chains. Leveraging on the quasi-one-dimensional geometry of Fluorapatite crystal spin systems, we can gain a deeper insight on the multi-spin states created by the coherent evolution, and their subsequent decay, than it is possible in 3D systems. We are then able to formulate an analytical model that captures the key features of the decay. We can thus compare the decoherence behavior for different initial states of the spin chain and link their decay rate to the state characteristics, in particular their coherence and long-range correlation among spins. Our experimental and theoretical study shows that the spin chains undergo a rich dynamics, with a slower decay rate than for the 3D case, and thus might be more amenable to decoupling techniques.

  2. Screw dislocation-driven growth of one-dimensional nanomaterials

    NASA Astrophysics Data System (ADS)

    Meng, Fei

    Nanoscience and nanotechnology are impacting our lives in many ways, from electronic and photonic devices to biosensors. They also hold the promise of tackling the renewable energy challenges facing us. However, one limiting scientific challenge is the effective and efficient bottom-up synthesis of nanomaterials. In this thesis, we discuss the fundamental theories of screw dislocation-driven growth of various nanostructures including one-dimensional nanowires and nanotubes, two-dimensional nanoplates, and three-dimensional hierarchical tree-like nanostructures. We then introduce the transmission electron microscopy (TEM) techniques to structurally characterize the dislocation-driven nanomaterials for future searching and identifying purposes. We summarize the guidelines for rationally designing the dislocation-driven growth and discuss specific examples to illustrate how to implement the guidelines. We also show that dislocation growth is a general and versatile mechanism that can be used to grow a variety of nanomaterials via distinct reaction chemistry and synthetic methods. The fundamental investigation and development of dislocation-driven growth of nanomaterials will create a new dimension to the rational design and synthesis of increasingly complex nanomaterials.

  3. A Smart Colorful Supercapacitor with One Dimensional Photonic Crystals

    PubMed Central

    Liu, Cihui; Liu, Xing; Xuan, Hongyun; Ren, Jiaoyu; Ge, Liqin

    2015-01-01

    To meet the pressing demands for portable and flexible equipment in contemporary society, developing flexible, lightweight, and sustainable supercapacitor systems with large power densities, long cycle life, and ease of strongly required. However, estimating the state-of-charge of existing supercapacitors is difficult, and thus their service life is limited. In this study, we fabricate a flexible color indicative supercapacitor device with mesoporous polyaniline (mPANI)/Poly(N-Isopropyl acrylamide-Graphene Oxide-Acrylic Acid) (P(NiPPAm-GO-AA)) one dimensional photonic crystals (1DPCs) as the electrode material through a low-cost, eco-friendly, and scalable fabrication process. We found that the state-of-charge could be monitored by the structural color oscillation due to the change in the photonic band gap position of the 1DPCs. The flexible 1DPCs supercapacitor is thin at 3?mm and exhibits good specific capacitance of 22.6?F g?1 with retention of 91.1% after 3,000 cycles. This study shows the application of the 1DPCs supercapacitor as a visual ultrathin power source. The technology may find many applications in future wearable electronics. PMID:26689375

  4. Predictions by Two One-Dimensional Cloud Models: A Comparison.

    NASA Astrophysics Data System (ADS)

    Ackerman, Bernice; Sun, Rueen-Yuh

    1985-07-01

    Two one-dimensional steady-state models of cumulus convection in common use in weather modification research, the NOAA Experimental Meteorology Branch model (EMB) and the Great Plains Cumulus Model (GPCM), differ in their formulations in several ways. Some of the differences arise from the conceptualization of the convective phenomenon which is modeled in each and some from the physical parameterizations utilized. Predictions of cloud top and dynamic modification potential (seedability) by the two models for 57 midday radiosondes in the Midwest, differed significantly, with the EMB values consistently higher. GPCM simulations provided a better overall estimate of observed radar echo tops, while EMB consistently overestimated, by largest amounts when tops were below 12 km. Study of the impact of temporal and/or spatial separation between sounding and cloud area emphasizes the need, in the Midwest, to consider factors other than thermodynamic stratification (e.g. forced lifting, convergence) on the synoptic and mesoscale when applying the model for prediction of cloud development. However, it was also found that the average difference in predictions by the two models, for the same sounding, was of the same order as the average difference in predictions arising from spatial or temporal separation.

  5. Spontaneous charge carrier localization in extended one-dimensional systems

    E-print Network

    Vl?ek, Vojt?ch; Steinle-Neumann, Gerd; Baer, Roi

    2015-01-01

    Charge carrier localization in extended atomic systems can be driven by disorder, point defects or distortions of the ionic lattice. Herein we give first-principles theoretical computational evidence that it can also appear as a purely electronic effect in otherwise perfectly ordered periodic structures. Optimally-tuned range separated density functional calculations reveal that in trans-polyacetylene and polythiophene the hole density localizes on a length scale of several nanometers. This is due to exchange induced translational symmetry breaking of the charge density. Ionization potentials, optical absorption peaks, excitonic binding energies and the optimally-tuned range parameter itself all become independent of polymer length when it exceeds the critical localization length scale. These first-principles findings show, for the first time, that charge localization is not caused by lattice distortion but it is rather its cause. This helps to explain experimental findings that polarons in conjugated polymer...

  6. Lanthanide coordination polymers based on multi-donor ligand containing pyridine and phthalate moieties: Structures, luminescence and magnetic properties

    SciTech Connect

    Feng, Xun; Liu, Lang; Wang, Li-Ya; Song, Hong-Liang; Qiang Shi, Zhi; Wu, Xu-Hong; Ng, Seik-Weng

    2013-10-15

    A new family of five lanthanide-organic coordination polymers incorporating multi-functional N-hetrocyclic dicarboxylate ligand, namely, [Ln{sub 2}(Hdpp){sub 2}(dpp){sub 2}]{sub n}Ln=Pr(1), Eu(2), Gd(3), Dy(4), Er(5) (H{sub 2}dpp=1-(3, 4-dicarboxyphenyl) pyridin-4-ol) have been fabricated successfully through solvothermal reaction of 1-(3,4-dicarboxyphenyl)-4-hydroxypyridin-1-ium chloride with trivalent lanthanide salts, and have been characterized systematically. The complexes 1–5 are isomorphous and isostructural. They all feature three dimensional (3D) frameworks based on the interconnection of 1D double chains composed of the binuclear moiety [Ln{sub 2}(Hdpp){sub 2}]{sup 4+} basic carboxylate as secondary building unit (SBU). The results of magnetic analysis shows the same bridging fashion of carboxylic group in this case results in the different magnetic properties occurring within lanthanide polymers. Moreover, the Eu(III) and Dy(III) complexes display characteristic luminescence emission in the visible regions. - Graphical abstract: A new family of lanthanide-organic frameworks incorporating multi-donor twisted ligand has been fabricated successfully, and has been characterized systematically. The complexes 1–5 are isostructural, and all feather three dimensional (3D) frameworks based on the interconnection of 1D double stride chains composed of the binuclear moiety [Ln{sub 2}(Hdpp){sub 2}]{sup 2+} basic carboxylate as secondary building unit (SBU). Display Omitted - Highlights: • New family of lanthanide–organic coordination polymers incorporating multifunctional N-hetrocyclic dicarboxylate ligand has been fabricated. • They have been characterized systematically. • They all feather three dimensional frameworks based on the binuclear moiety of [Ln{sub 2}(Hdpp){sub 2}]{sup 2+}. • The Eu(III) and Dy(III) analogues exhibit intense photoluminescence.

  7. The metallic state in disordered quasi-one-dimensional conductors

    E-print Network

    H. C. F. Martens; J. A. Reedijk; H. B. Brom; D. M. de Leeuw; R. Menon

    2000-05-30

    The unusual metallic state in conjugated polymers and single-walled carbon nanotubes is studied by dielectric spectroscopy (8--600 GHz). We have found an intriguing correlation between scattering time and plasma frequency. This relation excludes percolation models of the metallic state. Instead, the carrier dynamics can be understood in terms of the low density of delocalized states around the Fermi level, which arises from the competion between disorder-induced localization and interchain-interactions-induced delocalization.

  8. Robust Photocatalytic H2O2 Production by Octahedral Cd3(C3N3S3)2 Coordination Polymer under Visible Light

    NASA Astrophysics Data System (ADS)

    Zhuang, Huaqiang; Yang, Lifang; Xu, Jie; Li, Fuying; Zhang, Zizhong; Lin, Huaxiang; Long, Jinlin; Wang, Xuxu

    2015-11-01

    Herein, we reported a octahedral Cd3(C3N3S3)2 coordination polymer as a new noble metal-free photocatalyst for robust photocatalytic H2O2 production from methanol/water solution. The coordination polymer can give an unprecedented H2O2 yield of ca. 110.0?mmol?•?L?1?•?g?1 at pH?=?2.8 under visible light illumination. The characterization results clearly revealed that the photocatalytic H2O2 production proceeds by a pathway of two-electron reduction of O2 on the catalyst surface. This work showed the potential perspective of Mx(C3N3S3)y (M?=?transitional metals) coordination polymers as a series of new materials for solar energy storage and conversion.

  9. Robust Photocatalytic H2O2 Production by Octahedral Cd3(C3N3S3)2 Coordination Polymer under Visible Light

    PubMed Central

    Zhuang, Huaqiang; Yang, Lifang; Xu, Jie; Li, Fuying; Zhang, Zizhong; Lin, Huaxiang; Long, Jinlin; Wang, Xuxu

    2015-01-01

    Herein, we reported a octahedral Cd3(C3N3S3)2 coordination polymer as a new noble metal-free photocatalyst for robust photocatalytic H2O2 production from methanol/water solution. The coordination polymer can give an unprecedented H2O2 yield of ca. 110.0?mmol?•?L?1?•?g?1 at pH?=?2.8 under visible light illumination. The characterization results clearly revealed that the photocatalytic H2O2 production proceeds by a pathway of two-electron reduction of O2 on the catalyst surface. This work showed the potential perspective of Mx(C3N3S3)y (M?=?transitional metals) coordination polymers as a series of new materials for solar energy storage and conversion. PMID:26582652

  10. Robust Photocatalytic H2O2 Production by Octahedral Cd3(C3N3S3)2 Coordination Polymer under Visible Light.

    PubMed

    Zhuang, Huaqiang; Yang, Lifang; Xu, Jie; Li, Fuying; Zhang, Zizhong; Lin, Huaxiang; Long, Jinlin; Wang, Xuxu

    2015-01-01

    Herein, we reported a octahedral Cd3(C3N3S3)2 coordination polymer as a new noble metal-free photocatalyst for robust photocatalytic H2O2 production from methanol/water solution. The coordination polymer can give an unprecedented H2O2 yield of ca. 110.0?mmol?•?L(-1)?•?g(-1) at pH?=?2.8 under visible light illumination. The characterization results clearly revealed that the photocatalytic H2O2 production proceeds by a pathway of two-electron reduction of O2 on the catalyst surface. This work showed the potential perspective of Mx(C3N3S3)y (M?=?transitional metals) coordination polymers as a series of new materials for solar energy storage and conversion. PMID:26582652

  11. Exciton size and binding energy limitations in one-dimensional organic materials.

    PubMed

    Kraner, S; Scholz, R; Plasser, F; Koerner, C; Leo, K

    2015-12-28

    In current organic photovoltaic devices, the loss in energy caused by the charge transfer step necessary for exciton dissociation leads to a low open circuit voltage, being one of the main reasons for rather low power conversion efficiencies. A possible approach to avoid these losses is to tune the exciton binding energy to a value of the order of thermal energy, which would lead to free charges upon absorption of a photon, and therefore increase the power conversion efficiency towards the Shockley-Queisser limit. We determine the size of the excitons for different organic molecules and polymers by time dependent density functional theory calculations. For optically relevant transitions, the exciton size saturates around 0.7 nm for one-dimensional molecules with a size longer than about 4 nm. For the ladder-type polymer poly(benzimidazobenzophenanthroline), we obtain an exciton binding energy of about 0.3 eV, serving as a lower limit of the exciton binding energy for the organic materials investigated. Furthermore, we show that charge transfer transitions increase the exciton size and thus identify possible routes towards a further decrease of the exciton binding energy. PMID:26723709

  12. One-dimensional overdriven detonations with branched-chain kinetics

    NASA Astrophysics Data System (ADS)

    Sánchez, Antonio L.; Carretero, Manuel; Clavin, Paul; Williams, Forman A.

    2001-03-01

    The dynamics of time-dependent, planar propagation of gaseous detonations is addressed on the basis of a three-step chemistry model that describes branched-chain processes. Relevant nondimensional parameters are the ratio of the heat release to the thermal enthalpy at the Neumann state, the nondimensional activation energies for the initiation and branching steps, the ratio of the branching time to the initiation time and the ratio of the branching time to the recombination time. The limit of strong overdrive is considered, in which pressure remains constant downstream from the leading shock in the first approximation, and the ratio of specific heats ? is taken to be near unity. A two-term expansion in the strong overdrive factor is introduced, and an integral equation is derived describing the nonlinear dynamics and exhibiting a bifurcation parameter, the reciprocal of the product of (?-1), the nondimensional heat release and the nondimensional branching activation energy, with an acoustic correction. A stability analysis shows that, depending on values of the parameters, either the mode of lowest frequency or a mode of higher frequency may be most unstable. Numerical integrations exhibit different conditions under which oscillations die, low-frequency oscillations prevail, high-frequency oscillations prevail, highly nonlinear oscillations persist, or detonation failure occurs. This type of parametric analysis is feasible because of the relative simplicity of the model, which still is more realistic than a one-step, Arrhenius chemical approximation. In particular, by addressing the limit of slow radical recombination compared with branching, explicit results are derived for the critical value of the bifurcation parameter, involving the ratio of the recombination time to the induction time. The results help to clarify the general nature of one-dimensional detonation instability and provide simplifications that can be employed in efficiently relating gaseous detonation behavior to the true underlying chemistry.

  13. Heterolayered, one-dimensional nanobuilding block mat batteries.

    PubMed

    Choi, Keun-Ho; Cho, Sung-Ju; Chun, Sang-Jin; Yoo, Jong Tae; Lee, Chang Kee; Kim, Woong; Wu, Qinglin; Park, Sang-Bum; Choi, Don-Ha; Lee, Sun-Young; Lee, Sang-Young

    2014-10-01

    The rapidly approaching smart/wearable energy era necessitates advanced rechargeable power sources with reliable electrochemical properties and versatile form factors. Here, as a unique and promising energy storage system to address this issue, we demonstrate a new class of heterolayered, one-dimensional (1D) nanobuilding block mat (h-nanomat) battery based on unitized separator/electrode assembly (SEA) architecture. The unitized SEAs consist of wood cellulose nanofibril (CNF) separator membranes and metallic current collector-/polymeric binder-free electrodes comprising solely single-walled carbon nanotube (SWNT)-netted electrode active materials (LiFePO4 (cathode) and Li4Ti5O12 (anode) powders are chosen as model systems to explore the proof of concept for h-nanomat batteries). The nanoporous CNF separator plays a critical role in securing the tightly interlocked electrode-separator interface. The SWNTs in the SEAs exhibit multifunctional roles as electron conductive additives, binders, current collectors and also non-Faradaic active materials. This structural/physicochemical uniqueness of the SEAs allows significant improvements in the mass loading of electrode active materials, electron transport pathways, electrolyte accessibility and misalignment-proof of separator/electrode interface. As a result, the h-nanomat batteries, which are easily fabricated by stacking anode SEA and cathode SEA, provide unprecedented advances in the electrochemical performance, shape flexibility and safety tolerance far beyond those achievable with conventional battery technologies. We anticipate that the h-nanomat batteries will open 1D nanobuilding block-driven new architectural design/opportunity for development of next-generation energy storage systems. PMID:25226349

  14. One dimensional blood flow in a planetocentric orbit

    NASA Astrophysics Data System (ADS)

    Haranas, Ioannis; Gkigkitzis, Ioannis

    2012-05-01

    All life on earth is accustomed to the presence of gravity. When gravity is altered, biological processes can go awry. It is of great importance to ensure safety during a spaceflight. Long term exposure to microgravity can trigger detrimental physiological responses in the human body. Fluid redistribution coupled with fluid loss is one of the effects. In particular, in microgravity blood volume is shifted towards the thorax and head. Sympathetic nervous system-induced vasoconstriction is needed to maintain arterial pressure, while venoconstriction limits venous pooling of blood prevents further reductions in venous return of blood to the heart. In this paper, we modify an existing one dimensional blood flow model with the inclusion of the hydrostatic pressure gradient that further depends on the gravitational field modified by the oblateness and rotation of the Earth. We find that the velocity of the blood flow VB is inversely proportional to the blood specific volume d, also proportional to the oblateness harmonic coefficient J2, the angular velocity of the Earth ?E, and finally proportional to an arbitrary constant c. For c = -0.39073 and ?H = -0.5 mmHg, all orbits result to less blood flow velocities than that calculated on the surface of the Earth. From all considered orbits, elliptical polar orbit of eccentricity e = 0.2 exhibit the largest flow velocity VB = 1.031 m/s, followed by the orbits of inclination i = 45°and 0°. The Earth's oblateness and its rotation contribute a 0.7% difference to the blood flow velocity.

  15. Inelastic collapse in one-dimensional driven systems under gravity

    E-print Network

    Jun'ichi Wakou; Hiroyuki Kitagishi; Takahiro Sakaue; Hiizu Nakanishi

    2013-03-19

    We study the inelastic collapse in the one-dimensional $N$-particle systems in the situation where the system is driven from below under the gravity. We investigate the hard-sphere limit of the inelastic soft-sphere systems by numerical simulations to find how the collision rate per particle $n_{coll}$ increases as a function of the elastic constant of the sphere $k$ when the restitution coefficient $e$ is kept constant. For the systems with large enough $N \\agt 20$, we find three regimes in $e$ depending on the behavior of $n_{coll}$ in the hard-sphere limit: (i) uncollapsing regime for $1 \\ge e > e_{c1}$, where $n_{coll}$ converges to a finite value, (ii) logarithmically collapsing regime for $e_{c1} > e > e_{c2}$, where $n_{coll}$ diverges as $n_{coll} \\sim \\log k$, and (iii) power-law collapsing regime for $e_{c2} > e > 0$, where $n_{coll}$ diverges as $n_{coll} \\sim k^\\alpha$ with an exponent $\\alpha$ that depends on $N$. The power-law collapsing regime shrinks as $N$ decreases and seems not to exist for the system with N=3 while, for large $N$, the size of the uncollapsing and the logarithmically collapsing regime decreases as $e_{c1} \\simeq 1-2.6/N$ and $e_{c2} \\simeq 1-3.0/N$. We demonstrate that this difference between large and small systems exists already in the inelastic collapse without the external drive and the gravity.

  16. The one-dimensional Ly? forest power spectrum from BOSS

    NASA Astrophysics Data System (ADS)

    Palanque-Delabrouille, Nathalie; Yèche, Christophe; Borde, Arnaud; Le Goff, Jean-Marc; Rossi, Graziano; Viel, Matteo; Aubourg, Éric; Bailey, Stephen; Bautista, Julian; Blomqvist, Michael; Bolton, Adam; Bolton, James S.; Busca, Nicolás G.; Carithers, Bill; Croft, Rupert A. C.; Dawson, Kyle S.; Delubac, Timothée; Font-Ribera, Andreu; Ho, Shirley; Kirkby, David; Lee, Khee-Gan; Margala, Daniel; Miralda-Escudé, Jordi; Muna, Demitri; Myers, Adam D.; Noterdaeme, Pasquier; Pâris, Isabelle; Petitjean, Patrick; Pieri, Matthew M.; Rich, James; Rollinde, Emmanuel; Ross, Nicholas P.; Schlegel, David J.; Schneider, Donald P.; Slosar, Anže; Weinberg, David H.

    2013-11-01

    We have developed two independent methods for measuring the one-dimensional power spectrum of the transmitted flux in the Lyman-? forest. The first method is based on a Fourier transform and the second on a maximum-likelihood estimator. The two methods are independent and have different systematic uncertainties. Determination of the noise level in the data spectra was subject to a new treatment, because of its significant impact on the derived power spectrum. We applied the two methods to 13 821 quasar spectra from SDSS-III/BOSS DR9 selected from a larger sample of over 60 000 spectra on the basis of their high quality, high signal-to-noise ratio (S/N), and good spectral resolution. The power spectra measured using either approach are in good agreement over all twelve redshift bins from ?z? = 2.2 to ?z? = 4.4, and scales from 0.001 km s-1 to 0.02 km s-1. We determined the methodological andinstrumental systematic uncertainties of our measurements. We provide a preliminary cosmological interpretation of our measurements using available hydrodynamical simulations. The improvement in precision over previously published results from SDSS is a factor 2-3 for constraints on relevant cosmological parameters. For a ?CDM model and using a constraint on H0 that encompasses measurements based on the local distance ladder and on CMB anisotropies, we infer ?8 = 0.83 ± 0.03 and ns = 0.97 ± 0.02 based on H i absorption in the range 2.1 < z < 3.7. The measured values of the power spectrum and correlation matrices for all scales and all redshifts (full Tables 4 and 5) are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/559/A85

  17. Two 2D silver(I) coordination polymers derived from mixed ligands: Syntheses, structures, photoluminescent and thermal properties

    NASA Astrophysics Data System (ADS)

    Liu, Fu-Jing; Sun, Di; Li, Yun-Hua; Hao, Hong-Jun; Huang, Rong-Bin; Zheng, Lan-Sun

    2011-07-01

    Two isomers of the aminobenzonitrile were reacted with Ag 2O and phthalic acid under ultrasonic condition, yielding two coordination polymers (CPs) of the formula [Ag 2( o-abn)(pa)] n ( 1) and [Ag 4( m-abn)(pa) 2] n ( 2). They have been characterized by elemental analysis, IR spectrum and single crystal X-ray diffraction. Both complexes 1 and 2 are 2D sheet structures which contain two different Ag(I) aggregates, 1D silver helical chain and 2D silver sheet for 1 and 2, respectively. The o-abn in 1 adopts a rare tridentate ? 3- N, N' N' mode to bridge the neighboring 1D silver chains to form a 2D coordination network, while the m-abn ligand just acts as a monodentate N-donor in 2 and does not contribute to the extension of the 2D silver sheet to the higher dimensionality. As the change of the relative position of amino and cyano groups of the aminobenzonitrile ligand, the dimensionality of the Ag(I) aggregates in 1 and 2 increases from 1D to 2D, which indicates that the relative positions of amino and cyano groups of aminobenzonitrile play an important role in the formation of the diverse Ag(I) aggregates, as a consequence, different 2D coordination networks are produced. Additionally, results about emissive behaviors and thermal stabilities of them are discussed.

  18. Two Ag(I) coordination polymers derived from melamine and dicarboxylates: Syntheses, crystal structures and thermal stabilities

    NASA Astrophysics Data System (ADS)

    Li, Yun-Hua; Sun, Di; Luo, Geng-Geng; Liu, Fu-Jing; Hao, Hong-Jun; Wen, Yi-Mei; Zhao, Yang; Huang, Rong-Bin; Zheng, Lan-Sun

    2011-08-01

    Two mixed-ligand Ag(I) coordination polymers (CPs), [(NH 4)Ag 3(MA) 2(suc) 2] n ( 1), [Ag 2(MA) 2(adip)·CH 3OH·H 2O] n ( 2), (where MA = melamine, H 2suc = succinic acid, H 2adip = adipic acid) have been synthesized and structurally characterized by element analysis, IR and X-ray single-crystal diffraction. The CP 1 is a three-dimensional (3D) framework in which the MA acts as a tridentate ligand and suc 2- anion shows three types of coordination modes. Each Ag(I) ion acts as a 4-connected node to generate three- and six-membered cycles, as a result, the network can be simplified to be an overall multi-layered Kagomé topology. The CP 2 is a 2D single-layer structure constructed by tridentate MA ligands and adip 2- anions. The adjacent single-layers are inter-linked to form a double-layer 2D structure through the Ag⋯Ag interactions. Two CPs structurally vary from 2D sheet to 3D framework, which indicates that the different dicarboxylates and coordination modes of MA ligand have significant influence on the final structures. Moreover, the thermal stabilities of them were also discussed.

  19. Novel 1D coordination polymer {l_brace}Tm(Piv){sub 3{r_brace}n}: Synthesis, structure, magnetic properties and thermal behavior

    SciTech Connect

    Fomina, Irina; Dobrokhotova, Zhanna; Aleksandrov, Grygory; Emelina, Anna; Bykov, Mikhail; Bogomyakov, Artem; Puntus, Lada; Novotortsev, Vladimir; Eremenko, Igor

    2012-01-15

    The new 1D coordination polymer {l_brace}Tm(Piv){sub 3{r_brace}n} (1), where Piv=OOCBu{sup t-}, was synthesized in high yield (>95%) by the reaction of thulium acetate with pivalic acid in air at 100 Degree-Sign S. According to the X-ray diffraction data, the metal atoms in compound 1 are in an octahedral ligand environment unusual for lanthanides. The magnetic and luminescence properties of polymer 1, it's the solid-phase thermal decomposition in air and under argon, and the thermal behavior in the temperature range of -50 Horizontal-Ellipsis +50 Degree-Sign S were investigated. The vaporization process of complex 1 was studied by the Knudsen effusion method combined with mass-spectrometric analysis of the gas-phase composition in the temperature range of 570-680 K. - Graphical Abstract: Novel 1D coordination polymer {l_brace}Tm(Piv){sub 3{r_brace}n} was synthesized and studied by X-ray diffraction. The magnetic, luminescence properties, the thermal behavior and the volatility for the compound {l_brace}Tm(Piv){sub 3{r_brace}n} were investigated. Black-Small-Square Highlights: Black-Right-Pointing-Pointer We synthesized the coordination polymer {l_brace}Tm(Piv){sub 3{r_brace}n}. Black-Right-Pointing-Pointer Tm atoms in polymer have the coordination number 6. Black-Right-Pointing-Pointer Polymer exhibits blue-color emission at room temperature. Black-Right-Pointing-Pointer Polymer shows high thermal stability and volatility. Black-Right-Pointing-Pointer Polymer has no phase transitions in the range of -50 Horizontal-Ellipsis +50 Degree-Sign S.

  20. Ultra-sensitive thermal conductance measurement of one-dimensional nanostructures enhanced by differential bridge.

    PubMed

    Wingert, Matthew C; Chen, Zack C Y; Kwon, Shooshin; Xiang, Jie; Chen, Renkun

    2012-02-01

    Thermal conductivity of one-dimensional nanostructures, such as nanowires, nanotubes, and polymer chains, is of significant interest for understanding nanoscale thermal transport phenomena as well as for practical applications in nanoelectronics, energy conversion, and thermal management. Various techniques have been developed during the past decade for measuring this fundamental quantity at the individual nanostructure level. However, the sensitivity of these techniques is generally limited to 1 × 10(-9) W?K, which is inadequate for small diameter nanostructures that potentially possess thermal conductance ranging between 10(-11) and 10(-10) W?K. In this paper, we demonstrate an experimental technique which is capable of measuring thermal conductance of ?10(-11) W?K. The improved sensitivity is achieved by using an on-chip Wheatstone bridge circuit that overcomes several instrumentation issues. It provides a more effective method of characterizing the thermal properties of smaller and less conductive one-dimensional nanostructures. The best sensitivity experimentally achieved experienced a noise equivalent temperature below 0.5 mK and a minimum conductance measurement of 1 × 10(-11) W?K. Measuring the temperature fluctuation of both the four-point and bridge measurements over a 4 h time period shows a reduction in measured temperature fluctuation from 100 mK to 0.6 mK. Measurement of a 15 nm Ge nanowire and background conductance signal with no wire present demonstrates the increased sensitivity of the bridge method over the traditional four-point I-V measurement. This ultra-sensitive measurement platform allows for thermal measurements of materials at new size scales and will improve our understanding of thermal transport in nanoscale structures. PMID:22380117

  1. Ultra-sensitive thermal conductance measurement of one-dimensional nanostructures enhanced by differential bridge

    NASA Astrophysics Data System (ADS)

    Wingert, Matthew C.; Chen, Zack C. Y.; Kwon, Shooshin; Xiang, Jie; Chen, Renkun

    2012-02-01

    Thermal conductivity of one-dimensional nanostructures, such as nanowires, nanotubes, and polymer chains, is of significant interest for understanding nanoscale thermal transport phenomena as well as for practical applications in nanoelectronics, energy conversion, and thermal management. Various techniques have been developed during the past decade for measuring this fundamental quantity at the individual nanostructure level. However, the sensitivity of these techniques is generally limited to 1 × 10-9 W/K, which is inadequate for small diameter nanostructures that potentially possess thermal conductance ranging between 10-11 and 10-10 W/K. In this paper, we demonstrate an experimental technique which is capable of measuring thermal conductance of ˜10-11 W/K. The improved sensitivity is achieved by using an on-chip Wheatstone bridge circuit that overcomes several instrumentation issues. It provides a more effective method of characterizing the thermal properties of smaller and less conductive one-dimensional nanostructures. The best sensitivity experimentally achieved experienced a noise equivalent temperature below 0.5 mK and a minimum conductance measurement of 1 × 10-11 W/K. Measuring the temperature fluctuation of both the four-point and bridge measurements over a 4 h time period shows a reduction in measured temperature fluctuation from 100 mK to 0.6 mK. Measurement of a 15 nm Ge nanowire and background conductance signal with no wire present demonstrates the increased sensitivity of the bridge method over the traditional four-point I-V measurement. This ultra-sensitive measurement platform allows for thermal measurements of materials at new size scales and will improve our understanding of thermal transport in nanoscale structures.

  2. A string reaction coordinate for the folding of a polymer chain

    E-print Network

    Christian Leitold; Wolfgang Lechner; Christoph Dellago

    2015-01-16

    We investigate the crystallization mechanism of a single, flexible homopolymer chain with short range attractions. For a sufficiently narrow attractive well, the system undergoes a first-order like freezing transition from an expanded disordered coil to a compact crystalline state. Based on a maximum likelihood analysis of committor values computed for configurations obtained by Wang-Landau sampling, we construct a non-linear string reaction coordinate for the coil-to-crystal transition. In contrast to a linear reaction coordinate, the string reaction coordinate captures the effect of different degrees of freedom controlling different stages of the transition. Our analysis indicates that a combination of the energy and the global crystallinity parameter Q6 provide the most accurate measure for the progress of the transition. While the crystallinity parameter Q6 is most relevant in the initial stages of the crystallization, the later stages are dominated by a decrease in the potential energy.

  3. A string reaction coordinate for the folding of a polymer chain

    E-print Network

    Leitold, Christian; Dellago, Christoph

    2015-01-01

    We investigate the crystallization mechanism of a single, flexible homopolymer chain with short range attractions. For a sufficiently narrow attractive well, the system undergoes a first-order like freezing transition from an expanded disordered coil to a compact crystalline state. Based on a maximum likelihood analysis of committor values computed for configurations obtained by Wang-Landau sampling, we construct a non-linear string reaction coordinate for the coil-to-crystal transition. In contrast to a linear reaction coordinate, the string reaction coordinate captures the effect of different degrees of freedom controlling different stages of the transition. Our analysis indicates that a combination of the energy and the global crystallinity parameter Q6 provide the most accurate measure for the progress of the transition. While the crystallinity parameter Q6 is most relevant in the initial stages of the crystallization, the later stages are dominated by a decrease in the potential energy.

  4. A string reaction coordinate for the folding of a polymer chain

    NASA Astrophysics Data System (ADS)

    Leitold, Christian; Lechner, Wolfgang; Dellago, Christoph

    2015-05-01

    We investigate the crystallization mechanism of a single, flexible homopolymer chain with short range attractions. For a sufficiently narrow attractive well, the system undergoes a first-order like freezing transition from an expanded disordered coil to a compact crystalline state. Based on a maximum likelihood analysis of committor values computed for configurations obtained by Wang-Landau sampling, we construct a non-linear string reaction coordinate for the coil-to-crystal transition. In contrast to a linear reaction coordinate, the string reaction coordinate captures the effect of different degrees of freedom controlling different stages of the transition. Our analysis indicates that a combination of the energy and the global crystallinity parameter Q6 provide the most accurate measure for the progress of the transition. While the crystallinity paramter Q6 is most relevant in the initial stages of the crystallization, the later stages are dominated by a decrease in the potential energy.

  5. A string reaction coordinate for the folding of a polymer chain.

    PubMed

    Leitold, Christian; Lechner, Wolfgang; Dellago, Christoph

    2015-05-20

    We investigate the crystallization mechanism of a single, flexible homopolymer chain with short range attractions. For a sufficiently narrow attractive well, the system undergoes a first-order like freezing transition from an expanded disordered coil to a compact crystalline state. Based on a maximum likelihood analysis of committor values computed for configurations obtained by Wang-Landau sampling, we construct a non-linear string reaction coordinate for the coil-to-crystal transition. In contrast to a linear reaction coordinate, the string reaction coordinate captures the effect of different degrees of freedom controlling different stages of the transition. Our analysis indicates that a combination of the energy and the global crystallinity parameter Q6 provide the most accurate measure for the progress of the transition. While the crystallinity paramter Q6 is most relevant in the initial stages of the crystallization, the later stages are dominated by a decrease in the potential energy. PMID:25923377

  6. Gas adsorption/separation properties of metal directed self-assembly of two coordination polymers with 5-nitroisophthalate

    SciTech Connect

    Ar?c?, Mürsel; Ye?ilel, Okan Zafer; Keskin, Seda; ?ahin, Onur

    2014-02-15

    Two new coordination polymers, namely, [Co(µ-nip)(µ-bpe)]{sub n} (1) and [Zn(µ-nip)(µ-bpe)]{sub n} (2) (nip: 5-nitroisophthalate, bpe: 1,2-bis(4-pyridyl)ethane) were hydrothermally synthesized and structurally characterized by single crystal X-ray diffraction, IR spectroscopy, elemental analysis and thermal analysis. Moreover, atomically detailed simulation studies of complex 2 for CO{sub 2}/CH{sub 4} adsorption and separation were performed. Complex 1 consists of two dimensional (2D) (4,4) grid networks with the point symbol of 4{sup 4}.6{sup 2}. Complex 2 exhibits a 3-fold interpenetrating 3D framework with 6{sup 5}.8-dmp topology. Thermal properties of the complexes showed that both complexes were stable over 320 °C. Simulation studies demonstrated that complex 2 can separate CO{sub 2} from CH{sub 4} at low pressures at 273 K. - Graphical abstract: In this study, two new coordination polymers, namely, [Co(µ-nip)(µ-bpe)]{sub n} (1) and [Zn(µ-nip)(µ-bpe)]{sub n} (2) (nip: 5-nitroisophthalate, bpe: 1,2-bis(4-pyridyl)ethane) were hydrothermally synthesized and structurally characterized by single crystal X-ray diffraction, IR spectroscopy, elemental analysis and thermal analysis. Moreover, atomically detailed simulation studies of complex 2 for CO{sub 2}/CH{sub 4} adsorption and separation were performed. Complex 1 consists of two dimensional (2D) (4,4) grid networks with the point symbol of 4{sup 4}.6{sup 2}. Complex 2 exhibits a 3-fold interpenetrating 3D framework with 6{sup 5}.8-dmp topology. Simulation studies demonstrated that complex 2 can separate CO{sub 2} from CH{sub 4} at low pressures at 273 K. Display Omitted - Highlights: • Two new coordination polymers with 5-nitroisophthalate and 1,2-bis(4-pyridyl)ethane. • Atomically detailed simulation studies of the complexes. • Complex 2 can be proposed as molecular sieve to separate CO{sub 2} from CH{sub 4} at low pressures.

  7. Bioinspired one-dimensional materials for directional liquid transport.

    PubMed

    Ju, Jie; Zheng, Yongmei; Jiang, Lei

    2014-08-19

    One-dimensional materials (1D) capable of transporting liquid droplets directionally, such as spider silks and cactus spines, have recently been gathering scientists' attention due to their potential applications in microfluidics, textile dyeing, filtration, and smog removal. This remarkable property comes from the arrangement of the micro- and nanostructures on these organisms' surfaces, which have inspired chemists to develop methods to prepare surfaces with similar directional liquid transport ability. In this Account, we report our recent progress in understanding how this directional transport works, as well our advances in the design and fabrication of bioinspired 1D materials capable of transporting liquid droplets directionally. To begin, we first discuss some basic theories on droplet directional movement. Then, we discuss the mechanism of directional transport of water droplets on natural spider silks. Upon contact with water droplets, the spider silk undergoes what is known as a wet-rebuilt, which forms periodic spindle-knots and joints. We found that the resulting gradient of Laplace pressure and surface free energy between the spindle-knots and joints account for the cooperative driving forces to transport water droplets directionally. Next, we discuss the directional transport of water droplets on desert cactus. The integration of multilevel structures of the cactus and the resulting integration of multiple functions together allow the cactus spine to transport water droplets continuously from tip to base. Based on our studies of natural spider silks and cactus spines, we have prepared a series of artificial spider silks (A-SSs) and artificial cactus spines (A-CSs) with various methods. By changing the surface roughness and chemical compositions of the artificial spider silks' spindle-knots, or by introducing stimulus-responsive molecules, such as thermal-responsive and photoresponsive molecules, onto the spindle-knots, we can reversibly manipulate the direction of water droplet's movement on the prepared A-SSs. In addition, the A-SSs with nonuniform spindle-knots, such as multilevel sized spindle-knots and gradient spindle-knots, further demonstrate integrated directional transport ability for water droplets. Through mimicking the main principle of cactus spines in transporting water droplets, we were able to fabricate both single and array A-CSs, which are able to transport liquid droplets directionally both in air and under water. Lastly, we demonstrated some applications of this directional liquid transport, from aspects of efficient fog collection to oil/water separation. In addition, we showed some potential applications in smart catalysis, tracer substance enrichment, smog removal, and drug delivery. PMID:25019657

  8. Extracting complexity waveforms from one-dimensional signals

    PubMed Central

    Kalauzi, Aleksandar; Boji?, Tijana; Raki?, Ljubisav

    2009-01-01

    Background Nonlinear methods provide a direct way of estimating complexity of one-dimensional sampled signals through calculation of Higuchi's fractal dimension (1

  9. One-dimensional fast migration of vacancy clusters in metals

    SciTech Connect

    Matsukawa, Yoshitaka; Zinkle, Steven J

    2007-01-01

    The migration of point defects, e.g. crystal lattice vacancies and self-interstitial atoms (SIAs), typically occurs through three-dimensional (3-D) random walk. However, when vacancies and SIAs agglomerate with like defects forming clusters, the migration mode may change. Recently, atomic-scale computer simulations using molecular dynamics (MD) codes have reported that nanometer-sized two-dimensional (2-D) clusters of SIAs exhibit one-dimensional (1-D) fast migration1-7. The 1-D migration mode transports the entire cluster containing several tens of SIAs with a mobility comparable to single SIAs3. This anisotropic migration of SIA clusters can have a significant impact on the evolution of a material fs neutron-irradiation damage microstructure, which dominates the material fs lifetime in nuclear reactor environments8-9. This is also proposed to be a key physical mechanism for the self-organization of nanometer-sized sessile vacancy cluster arrays10-13. Given these findings for SIA clusters, a fundamental question is whether the 1-D migration mode is also possible for 2-D clusters of vacancies. Preceding MD results predicted that 1-D migration of vacancy clusters is possible in body-centered cubic (bcc) iron, but not in face-centered cubic (fcc) copper2. Previous experimental studies have reported 1-D migration of SIA clusters14, but there have been no observations of 1-D vacancy cluster migration. Here we present the first experimental transmission electron microscopy (TEM) dynamic observation demonstrating the 1-D migration of vacancy clusters in fcc gold. It was found that the mobility of the vacancy clusters via the 1-D migration is much higher than single vacancies via 3-D random walk and comparable to single SIAs via 3-D random walk. Hence, the mobility of the glissile clusters is not associated with the character of their constituent point defects. Dynamic conversion of a planar vacancy loop into a 3-D stacking fault tetrahedron geometry was also observed.

  10. Strong correlations and topological order in one-dimensional systems

    NASA Astrophysics Data System (ADS)

    De Gottardi, Wade Wells

    This thesis presents theoretical studies of strongly correlated systems as well as topologically ordered systems in 1D. Non-Fermi liquid behavior characteristic of interacting 1D electron systems is investigated with an emphasis on experimentally relevant setups and observables. The existence of end Majorana fermions in a 1D p-wave superconductor subject to periodic, incommensurate and disordered potentials is studied. The Tomonaga-Luttinger liquid (TLL), a model of interacting electrons in one spatial dimension, is considered in the context of two systems of experimental interest. First, a study of the electronic properties of single-walled armchair carbon nanotubes in the presence of transverse electric and magnetic fields is presented. As a result of their effect on the band structure and electron wave functions, fields alter the nature of the (effective) Coulomb interaction in tubes. In particular, it is found that fields couple to nanotube bands (or valleys), a quantum degree of freedom inherited from the underlying graphene lattice. As revealed by a detailed TLL calculation, it is predicted that fields induce electrons to disperse into their spin, band, and charge components. Fields also provide a means of tuning the shell-filling behavior associated with short tubes. The phenomenon of charge fractionalization is investigated in a one-dimensional ring. TLL theory predicts that momentum-resolved electrons injected into the ring will fractionalize into clockwise- and counterclockwise-moving quasiparticles. As a complement to transport measurements in quantum wires connected to leads, non-invasive measures involving the magnetic field profiles around the ring are proposed. Topological aspects of 1D p-wave superconductors are explored. The intimate connection between non-trivial topology (fermions) and spontaneous symmetry breaking (spins) in one-dimension is investigated. Building on this connection, a spin ladder system endowed with vortex degrees of freedom is proposed in order to study the effects that inhomogeneous potentials have on the topological phase diagram. Periodic vortex patterns yield a rich parameter space for tuning into a topologically non-trivial phase. This analysis hinges on the development of a topological invariant based on the wave function of Majorana fermions which inhabit the ends of the system and are robust to disorder. The method is generalized to aperiodic and disordered potentials. The topological phase diagram of such systems is studied; numerical and analytic results are found to be in close agreement.

  11. Transport and EPR studies of polyaniline: A quasi-one-dimensional conductor with three-dimensional ``metallic'' states

    NASA Astrophysics Data System (ADS)

    Wang, Z. H.; Scherr, E. M.; MacDiarmid, A. G.; Epstein, A. J.

    1992-02-01

    It is an open question if ``metallic'' polymers have one-dimensional or three-dimensional conduction states. We investigate this issue by studying a model polymer, the HCl-doped emeraldine salt form of oriented polyaniline (PAN-ES) through the temperature dependence of the dc conductivity, thermoelectric power, complex microwave dielectric constant, electron paramagnetic resonance (EPR), and electric-field dependence of conductivity. The thermopower, microwave dielectric constant, and EPR data suggest that the electrons are three dimensionally delocalized. We propose that oriented PAN-ES consists of coupled parallel chains that form ``metallic'' bundles. These bundles are the ``crystalline'' regions of the polymer in which the electron wave functions are three dimensionally extended. This is in contrast to conventional quasi-one-dimensional conductors (many ``metallic'' charge-transfer salts) in which conducting chains are essentially isolated. However, between bundles are the amorphous (less-ordered) regions in which charge hopping dominates the macroscopic conductivity. The formation of the ``metallic'' bundles is proposed to be the result of a significant charge-interchain-transfer rate inside the crystalline regions. The implications of the results for the improvement of conductivity are addressed.

  12. Time Dependent Monochromatic Scattering of Radiation in One Dimensional Media: Analytical and Numerical Solutions

    E-print Network

    D. I. Nagirner; S. L. Kirusheva

    2008-08-25

    In order to choose a numerical method for solving the time dependent equations of radiative transport, we obtain an exact solution for the time dependent radiation field in a one dimensional infinite medium with monochromatic, isotropic scattering for sources with an arbitrary spatial distribution and an arbitrary time variation of their power. The Lax-Wendroff method seems to be the most suitable. Because it is assumed that radiation delay is caused by the finite speed of light, the following difficulty arises when the numerical method is used: the region of variation of the variables (dimensionless coordinate \\tau and time t) is triangular (the inequality \\tauexpanding the unknown functions in series in terms of small values of the time and coordinate. By comparing the numerical and exact solutions for a point source with a given time dependence for its power and with pure scattering, the steps in the variables required to obtain a desired accuracy are estimated. This numerical method can be used to calculate the intensity and polarization of the radiation from sources in the early universe during epochs close to the recombination epoch.

  13. Lamb wave band gaps in one-dimensional radial phononic crystal slabs

    NASA Astrophysics Data System (ADS)

    Li, Yinggang; Chen, Tianning; Wang, Xiaopeng

    2015-10-01

    In this paper, we theoretically investigate the band structures of Lamb wave in one-dimensional radial phononic crystal (PC) slabs composed of a series of alternating strips of epoxy and aluminum. The dispersion relations, the power transmission spectra and the displacement fields of the eigenmodes are calculated by using the finite element method based on two-dimensional axial symmetry models in cylindrical coordinates. The axial symmetry model is validated by three-dimensional finite element model in Cartesian coordinates. Numerical results show that the proposed radial PC slabs can yield several complete band gaps with a variable bandwidth exist for elastic waves. Furthermore, the effects of the filling fraction and the slab thickness on the band gaps are further explored numerically. It is worth observing that, with the increase of the filling fraction, both the lower and upper edges of the band gaps are simultaneously shifted to higher frequency, which results from the enhancement interaction between the rigid resonance of the scatterer and the matrix. The slab thickness is the key parameter for the existence and the width of complete band gaps in the radial PC slabs. These properties of Lamb waves in the radial PC plates can potentially be applied to optimize band gaps, generate filters and design acoustic devices in the rotary machines and structures.

  14. Syntheses, crystal structures and properties of series of 4d-4f ln(III)-Ag(I) heterometallic coordination polymers

    NASA Astrophysics Data System (ADS)

    Ran, Xing-Rui; Wang, Ning; Xie, Wei-Ping; Xiong, Yan-Ju; Cheng, Qian; Long, Yi; Yue, Shan-Tang; Liu, Ying-Liang

    2015-05-01

    By control of the experimental parameters such as ligands, pH value and reacting temperature, series of three-dimensional (3D) 4d-4f Ln(III)-Ag(I) porous coordination polymers (PCPs) with interesting chain-layer construction, namely, {[LnIIIAgI(na)(ina)(ox)]·2(H2O)}n [Ln=Sm(1), Eu(2), Gd(3), Tb(4), Dy(5), Ho(6), Y(7), Yb(8)], have been successfully synthesized under hydrothermal conditions and structurally characterized. All the complexes are characterized by elemental analyses, FT-IR spectroscopy, Powder X-ray diffraction (PXRD) and thermogravimetric analyses (TGA). Furthermore, the luminescence properties of compounds 2 and 4 and the magsnetic properties of complexes 3 and 5 were also investigated in detail.

  15. Tuning structural topologies of two new luminescent Zn(II) coordination polymers via varying organic carboxylate ligands

    NASA Astrophysics Data System (ADS)

    Zhang, Yan; Liu, Qi-Feng; Xing, Guang'en; Zhang, Zhong-Qiang

    2015-04-01

    Presented here are two new luminescent Zn(II) coordination polymers, [Zn3(pdc)3(Hmtz)]n (1) and [Zn3(ntd)(mtz)4(DMA)2]n (2) (H2pdc = terephthalic acid, H2ntd = 2,6-naphthalenedicarboxylic acid, Hmtz = 5-methyl-1H-tetrazole). Single crystal X-ray diffraction analysis reveals that compound 1 features a 8-connected hex topological framework with the schläfli symbol of {36.418.53.6}, while compound 2 features a (3,4)-connected tfi topological framework with the schläfli symbol of {62.84}{62.8}2. The thermal stabilities and luminescent properties of 1-2 were also investigated.

  16. DNA damage induced by bare and loaded microporous coordination polymers from their ground and electronic excited states.

    PubMed

    Yañuk, Juan G; Alomar, María L; Gonzalez, M Micaela; Simon, Francisco; Erra-Balsells, Rosa; Rafti, Matías; Cabrerizo, Franco M

    2015-05-21

    We report on interactions of cell free double-stranded DNA (dsDNA) with a selected subgroup of Microporous Coordination Polymers (MCPs). In particular, we have studied the influence of different metal ion constituents and chemically modified linkers using a set of five benzene carboxylate-based MCPs. Our results suggest that the DNA moiety can be structurally modified in two different ways: by direct MCPs-dsDNA interaction and/or through photosensitized processes. The extent of the observed damage was found to be strongly dependent on the charge density of the material. The potential use of the MCPs tested as inert carriers of photosensitizers was demonstrated by analyzing the interaction between dsDNA and harmine-loaded Cr-based materials, both in the absence of light and upon UVA irradiation. PMID:25908554

  17. Effect of Solvent Molecule in Pore for Flexible Porous Coordination Polymer upon Gas Adsorption and Iodine Encapsulation.

    PubMed

    Ar?c?, Mürsel; Ye?ilel, Okan Zafer; Ta?, Murat; Demiral, Hakan

    2015-12-01

    Four new Zn(II)-coordination polymers, namely, [Zn2(?6-ao2btc)(?-obix)2]n (1), [Zn2(?4-ao2btc)(?-obix)2]n (2), [Zn2(?4-ao2btc)(?-mbix)2]n (3), and {[Zn2(?4-ao2btc)(?-pbix)2]·2DMF·8H2O}n (4), where ao2btc = dioxygenated form of 3,3',5,5'-azobenzenetetracarboxylate and obix, mbix, and pbix = 1,2-, 1,3-, and 1,4-bis(imidazol-1-ylmethyl)benzene, have been synthesized with azobenzenetetracarboxylic acid and isomeric bis(imidazole) ligands and characterized by elemental analyses, IR spectra, single-crystal X-ray diffraction, powder X-ray diffraction, and thermal analyses. X-ray results showed that 1, 2, and 4 had two-dimensional structures with 3,4L13 topology, while 3 was a three-dimensional coordination polymer with bbf topology. For 4, two types of activation strategies, solvent exchange + heating (which produced 4a) and direct heating (which produced 4b), were used to investigate the effect of a guest molecule in a flexible framework. Gas adsorption and iodine encapsulation properties of activated complexes were studied. The CO2 uptake capacities for 4a and 4b were 3.62% and 9.50%, respectively, and Langmuir surface areas calculated from CO2 isotherms were 167.4 and 350.7 m(2)/g, respectively. Moreover, 4b exhibited 19.65% and 15.27% iodine uptake in vapor phase and cyclohexane solution, respectively, which corresponded to 1.47 and 0.97 molecules of iodine/formula unit, respectively. Moreover, photoluminescence properties of the complexes were studied. PMID:26594910

  18. Applications of One-Dimensional Nanomaterials for Stretchable Electronics

    NASA Astrophysics Data System (ADS)

    Xu, Feng

    Electronics that can be stretched and/or conformal to curvilinear surfaces has recently attracted broad attention. Success of stretchable electronics depends on the availability of electronic materials and structures that can be highly stretched, compressed, bent, and twisted. One-dimensional (1D) nanomaterials are expected to aid the development of the stretchable electronic systems by improving performance, expanding integration possibilities, and potentially lowering cost, due to their superior mechanical/electronic/optical properties, high aspect ratios, and compatibility with bulk synthesis. This dissertation is primarily focused on the application of 1D nanomaterials, including silicon nanowires (SiNWs), carbon nanotubes (CNTs) and silver nanowires (AgNWs) for stretchable electronics. The mechanical properties of SiNWs, grown by the vapor-liquid-solid process, were first studied with in situ tensile tests inside a scanning electron microscope (SEM). It was found that the fracture strain increased from 2.7% to about 12% when the NW diameter decreased from 60 to 15 nm. The Young's modulus decreased while the fracture strength increased up to 12.2 GPa, as the nanowire diameter decreased. The fracture strength also increased with the decrease of the side surface area. Repeated loading and unloading during tensile tests demonstrated that the nanowires are linear elastic until fracture without appreciable plasticity. Then, SiNW coils were fabricated on elastomeric substrates by a controlled buckling process. SiNWs were first transferred onto prestrained and ultraviolet/ozone (UVO)-treated poly(dimethylsiloxane) (PDMS) substrates and buckled upon release of the prestrain. Two buckling modes (the in-plane wavy mode and the three-dimensional coiled mode) were found; a transition between them was achieved by controlling the UVO treatment of PDMS. Structural characterization revealed that the NW coils were oval-shaped. The oval-shaped NW coils exhibited very large stretchability up to the failure strain of PDMS (˜104% in our study). Such a large stretchability relies on the effectiveness of the coil shape in mitigating the maximum local strain, with a mechanics that is similar to the motion of a coil spring. Single NW devices based on coiled NWs were demonstrated with a nearly constant electrical response in a large strain range. In addition to the wavy shape, the coil shape represents an effective architecture in accommodating large tension, compression, bending, and twist, which may find important applications for stretchable electronics and other stretchable technologies. For CNTs, wavy CNT ribbons coated with a thin layer of Au/Pd film were fabricated on PDMS substrates through mechanical buckling. Covered with a top layer of PDMS, the wavy CNT ribbons are able to accommodate large stretching (up to 100%) with little change in resistance. Significantly, a new manufacturing strategy for buckling of aligned CNTs was developed, which does not involve prestretching the substrate but relies on the interface interaction between the CNTs and the substrate. More specifically, upon stretching the substrate the CNTs slide on the substrate, but upon releasing the CNTs buckle. Following this manufacturing strategy, stretchable conductors based on aligned CNTs were demonstrated. At last, a highly conductive and stretchable conductor with AgNWs embedded just below the surface of PDMS was fabricated. Stable conductivity of 5,285 S cm-1 was achieved in a large range of tensile strain (0-50%) after a few cycles of stretching/releasing of the substrate. This stable electric response is due to buckling of the AgNW/PDMS thin layer, which is attributed to irreversible sliding of the AgNWs in the PDMS matrix. AgNWs can be printed to fabricate patterned stretchable conductors with feature size as small as 50 microm. Furthermore, a stretchable light emitting diode (LED) circuit and a capacitive strain sensor were demonstrated using the AgNW-based stretchable conductors as interconnects or electrodes.

  19. Reversible Guest Binding in a Non-Porous Fe(II) Coordination Polymer Host Toggles Spin Crossover.

    PubMed

    Lennartson, Anders; Southon, Peter; Sciortino, Natasha F; Kepert, Cameron J; Frandsen, Cathrine; Mørup, Steen; Piligkos, Stergios; McKenzie, Christine J

    2015-11-01

    Formation of either a dimetallic compound or a 1?D coordination polymer of adiponitrile adducts of [Fe(bpte)](2+) (bpte=[1,2-bis(pyridin-2-ylmethyl)thio]ethane) can be controlled by the choice of counteranion. The iron(II) atoms of the bis(adiponitrile)-bridged dimeric complex [Fe2 (bpte)2 (?2 -(NC(CH2 )4 CN)2 ](SbF6 )4 (2) are low spin at room temperature, as are those in the polymeric adiponitrile-linked acetone solvate polymer {[Fe(bpte)(?2 -NC(CH2 )4 CN)](BPh4 )2 ?Me2 CO} (3?Me2 CO). On heating 3?Me2 CO to 80?°C, the acetone is abruptly removed with an accompanying purple to dull lavender colour change corresponding to a conversion to a high-spin compound. Cooling reveals that the desolvate 3 shows hysteretic and abrupt spin crossover (SCO) S=0?S=2 behaviour centred at 205?K. Non-porous 3 can reversibly absorb one equivalent of acetone per iron centre to regenerate the same crystalline phase of 3?Me2 CO concurrently reinstating a low-spin state. PMID:26394897

  20. The coordination polymer [Zn3(OAc)4(4,4'-bpy)3 {N(CN)2}2] is prepared and characterized by X-ray diffraction

    E-print Network

    Gao, Song

    -assembled coordination polymers with spe- cific network topologies is expanding rapidly because of their potential that 1 adopts an infinite three-leg lad- der structure. As shown in Figure 1, ZnII ions located ligands. Scheme 2 illustrates the crystal packing of the ladders. Two infinite ladders are juxtaposed

  1. Multifunctional Magnetic Gd(3+) -Based Coordination Polymer Nanoparticles: Combination of Magnetic Resonance and Multispectral Optoacoustic Detections for Tumor-Targeted Imaging in vivo.

    PubMed

    An, Qiao; Liu, Jing; Yu, Meng; Wan, Jiaxun; Li, Dian; Wang, Changchun; Chen, Chunying; Guo, Jia

    2015-11-01

    To overcome traditional barriers in optical imaging and microscopy, optoacoustic-imaging has been changed to combine the accuracy of spectroscopy with the depth resolution of ultrasound, achieving a novel modality with powerful in vivo imaging. However, magnetic resonance imaging provides better spatial and anatomical resolution. Thus, a single hybrid nanoprobe that allows for simultaneous multimodal imaging is significant not only for cutting edge research in imaging science, but also for accurate clinical diagnosis. A core-shell-structured coordination polymer composite microsphere has been designed for in vivo multimodality imaging. It consists of a Fe3 O4 nanocluster core, a carbon sandwiched layer, and a carbocyanine-Gd(III) (Cy-Gd(III) ) coordination polymer outer shell (Fe3 O4 @C@Cy-Gd(III) ). Folic acid-conjugated poly(ethylene glycol) chains are embedded within the coordination polymer shell to achieve extended circulation and targeted delivery of probe particles in vivo. Control of Fe3 O4 core grain sizes results in optimal r2 relaxivity (224.5 × 10(-3) m(-1) s(-1) ) for T2 -weighted magnetic resonance imaging. Cy-Gd(III) coordination polymers are also regulated to obtain a maximum 25.1% of Cy ligands and 5.2% of Gd(III) ions for near-infrared fluorescence and T1 -weighted magnetic resonance imaging, respectively. The results demonstrate their impressive abilities for targeted, multimodal, and reliable imaging. PMID:26366746

  2. Unique electrocatalytic activity of a nucleic acid-mimicking coordination polymer for the sensitive detection of coenzyme A and histone acetyltransferase activity.

    PubMed

    Hu, Yufang; Chen, Siyu; Han, Yitao; Chen, Hongjun; Wang, Qin; Nie, Zhou; Huang, Yan; Yao, Shouzhuo

    2015-12-01

    A nucleic acid-mimicking CoA-Ag(i) coordination polymer (CP) was in situ prepared and its unique electrocatalytic activity to H2O2 reduction was discovered. Based on it, a novel, label-free electrochemical sensor has been developed for the sensitive detection of coenzyme A (CoA) and histone acetyltransferase (HAT) activity. PMID:26483158

  3. Structure modulation of manganese coordination polymers consisting of 1,4-naphthalene dicarboxylate and 1,10-phenanthroline.

    PubMed

    Lou, Yongbing; Wang, Jingjing; Tao, Yinhua; Chen, Jinxi; Mishima, Akio; Ohba, Masaaki

    2014-06-14

    Three new manganese coordination polymers, {[Mn2(1,4-NDC)2(phen)2](H2O)}n (1), [Mn2(1,4-NDC)2(phen)(H2O)]n (2) and {[Mn4(1,4-NDC)4(phen)4](DMF)2}n (3) (1,4-H2NDC = 1,4-naphthalene dicarboxylic acid; phen = 1,10-phenanthroline; DMF = N,N-dimethylformamide), have been synthesized solvo/hydrothermally. 1,4-NDC(2-) ligands adopt different coordination modes under different solvents and concentrations which promotes different crystal structure formation. X-ray crystal structural data reveal that compounds 1, 2 and 3 crystallize in monoclinic space groups C2/c, P21/c and C2/c, respectively. Compound 1 has Mn2 dimers connected by 1,4-NDC(2-) linkers, packing into a 2D structure in a grid pattern. Compound 2 has a three-dimensional (3D) structure which is constructed by Mn2 dimers and 1,4-NDC(2-) linkers. Each MnO4N2 node of compound 3 is linked to another by 1,4-NDC(2-) ligands to form a two-dimensional (2D) structure. Variable-temperature magnetic susceptibilities of compounds 1-3 exhibit overall weak antiferromagnetic coupling between the adjacent Mn(II) ions. PMID:24756312

  4. Synthesis, structures, luminescent and magnetic properties of four coordination polymers with the flexible 1,3-phenylenediacetate ligands

    SciTech Connect

    Gu, Jin-Zhong; Lv, Dong-Yu; Gao, Zhu-Qing; Liu, Jian-Zhao; Dou, Wei; Tang, Yu

    2011-03-15

    Four coordination polymers, [Zn(pda)(bpy)(H{sub 2}O)]{sub n}.nH{sub 2}O (1), [Cd(pda)(prz)(H{sub 2}O)]{sub n} (2), [Co{sub 3}({mu}{sub 3}-OH){sub 2}(pda){sub 2}(pyz)]{sub n}.2nH{sub 2}O (3) and [Pr{sub 2}(pda){sub 3}(H{sub 2}O){sub 2}]{sub n} (4) (H{sub 2}pda=1,3-phenylendiacetic acid, bpy=4,4'-bipyridine, prz=piperazine and pyz=pyrazine) have been hydrothermally synthesized and characterized. Complex 1 is a 1D wheel-like chain structure, which is further extended into a 3D metal-organic supramolecular framework by H-bonds and {pi}-{pi} stacking interactions. Complex 2 is a 1D ladder-like chain structure, which is also further extended into a 3D metal-organic supramolecular framework by H-bonds. Complex 3 possess a 2D sheet structure with infrequent two pairs of double-helix chains. Complex 4 features a 3D structure. Both 1 and 2 display strong blue fluorescent emission at room temperature. Magnetic susceptibility measurements of complexes 3 and 4 exhibit antiferromagnetic interactions between the nearest metal ions, with C=9.99 and 3.43 cm{sup 3} mol{sup -1} K, and {theta}=-23.9 and -46.3 K, respectively. -- Graphical abstract: Four new coordination polymers with 1,3-phenylenediacetate ligands have been hydrothermally synthesized and characterized. Complexes 1 and 2 display strong blue fluorescent emission at room temperature. Magnetic susceptibility measurements of 3 and 4 exhibit antiferromagnetic interactions between the nearest metal centers. Display Omitted Research highlights: > Coordinative property of H{sub 2}pda ligand was shown when bonded by different block metals. > Careful selection of co-ligand and metals resulted in dramatic framework evolution. > (c) The compounds constructed with Zn{sup 2+} and Cd{sup 2+} exhibit strong blue fluorescent emission. > The magneto-structural correlation of the complexes constructed with Co{sup 2+} and Pr{sup 3+} was elucidated.

  5. A series of M-M' heterometallic coordination polymers: syntheses, structures and surface photoelectric properties (M=Ni/Co, M'=Cd/Zn)

    SciTech Connect

    Li, Lei; Niu, Shu-Yun; Jin, Jing; Meng, Qin; Chi, Yu-Xian; Xing, Yong-Heng; Zhang, Guang-Ning

    2011-05-15

    Four new heterometallic polymers, [NiCd(mal){sub 2}(H{sub 2}O){sub 2}]n.2nH{sub 2}O 1, [NiZn{sub 2}(Hcit){sub 2}(H{sub 2}O){sub 2}]n 2, [CoCd{sub 2}(Hcit){sub 2}(H{sub 2}O){sub 2}]n 3, [CoZn{sub 2}(Hcit){sub 2}(H{sub 2}O){sub 2}]n 4 (H{sub 2}mal=malonic acid, H{sub 4}cit=citric acid) were synthesized and characterized. The photoelectric properties of the polymers were discussed by the surface photovoltage spectroscopy (SPS). The structural analyses indicate 1 is a Ni-Cd heterometallic polymer with 3D structure bridged by the mal{sup 2-} group. 2-4 are all heterometallic polymers with 2D structures bridged by the Hcit{sup 3-} group. The results of SPS for the four polymers reveal that there are wide photovoltage response bands in the range of 300-800 nm, which indicates that they all possess photoelectric conversion properties. By the introduction of the other metals, the SPS of heterometallic polymers are broadened obviously than the SPS of monometallic complexes. Moreover, the relationships between SPS and UV-Vis absorption spectra have been discussed. -- Graphical Abstract: Four heterometallic polymers, Ni-Cd, Ni-Zn, Co-Cd, Co-Zn, were synthesized and characterized. The photoelectric properties of heterometallic polymers were discussed by SPS. The introduction of heterometallic ions will broaden the SPS of corresponded monometallic complexes. Display Omitted highlights: > Four new heterometallic coordination polymers were reported. > The surface photoelectric properties of heterometallic polymers were studied by SPS. > They all possess photoelectric conversion properties. > The SPS of heterometallic polymers are broadened than that of monometallic complexes.

  6. Template-assisted electrodeposition of one-dimensional nanostructures for sensing and solar energy applications

    NASA Astrophysics Data System (ADS)

    Hernandez-Pagan, Emil A.

    One-dimensional nanowires and nanotubes offer unique properties that cannot be achieved with bulk materials. High surface area, strain relaxation, quantum confinement, and orthogonal light absorption and charge separation are examples. In this work, conducting polymer nanowires were synthesized by template-assisted electrodeposition. The dimensions of the nanowires could be easily controlled, and arrays or individual nanowires could be obtained. The conducting polymers synthesized were polypyrrole and poly(3,4-ethylendioxythiophene), as well as palladium-polymer and platinum-polymer composites. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) / energy-dispersive X-ray spectroscopy (EDS) were employed for structural characterization. Integration of the nanowires onto test structures was carried through electrofluidic assembly. Once assembled, the electrical properties of individual nanowires were investigated and studied for sensing of various gases. Template-assisted electrodeposition was also employed to synthesize cadmium selenide (CdSe) and copper indium diselenide (CuInSe2) nanowires. The crystal structure and crystallite domain size of the CdSe nanowires was controlled by either direct electrodeposition from an electrolyte that contained both elements or by topochemical cation exchange starting from crystalline t-Se nanowires. This was confirmed by TEM, X-ray Diffraction (XRD), and electron diffraction. CdSe nanowire photoanodes were used to study the effects of crystallite domain size on the photoelectrochemical properties. CuInSe2 nanowires were characterized by SEM, TEM/EDS, XRD, inductively coupled plasma mass spectrometry, Mott-Schottky analysis, and single wire electrical measurements. It was demonstrated that single phase p- and n-type CuInSe2 nanowires could be fabricated by this method. Since micro and nanowire arrays coupled to inexpensive catalysts are promising materials for unassisted-overall water splitting, the viability of membrane-based electrolytic cells was investigated. The challenge is to find conditions under which the cell can operate at solar flux (25 mA/cm 2) and near neutral pH without significant series resistance. Potential losses (DeltaE = iR + Em + EpH + Ecathode + Eanode) were analyzed with anion exchanger membranes and different buffers. It was discovered that monoprotic buffers gave minimal transmembrane pH gradients because of fast permeation of the membrane by the neutral acid. With these membrane/buffer combinations, it should be possible to separate the products of photoelectrolysis with low series resistance over a broad range of operating pH.

  7. Semiflexible macromolecules in quasi-one-dimensional confinement: Discrete versus continuous bond angles

    NASA Astrophysics Data System (ADS)

    Huang, Aiqun; Hsu, Hsiao-Ping; Bhattacharya, Aniket; Binder, Kurt

    2015-12-01

    The conformations of semiflexible polymers in two dimensions confined in a strip of width D are studied by computer simulations, investigating two different models for the mechanism by which chain stiffness is realized. One model (studied by molecular dynamics) is a bead-spring model in the continuum, where stiffness is controlled by a bond angle potential allowing for arbitrary bond angles. The other model (studied by Monte Carlo) is a self-avoiding walk chain on the square lattice, where only discrete bond angles (0° and ±90°) are possible, and the bond angle potential then controls the density of kinks along the chain contour. The first model is a crude description of DNA-like biopolymers, while the second model (roughly) describes synthetic polymers like alkane chains. It is first demonstrated that in the bulk the crossover from rods to self-avoiding walks for both models is very similar, when one studies average chain linear dimensions, transverse fluctuations, etc., despite their differences in local conformations. However, in quasi-one-dimensional confinement two significant differences between both models occur: (i) The persistence length (extracted from the average cosine of the bond angle) gets renormalized for the lattice model when D gets less than the bulk persistence length, while in the continuum model it stays unchanged. (ii) The monomer density near the repulsive walls for semiflexible polymers is compatible with a power law predicted for the Kratky-Porod model in the case of the bead-spring model, while for the lattice case it tends to a nonzero constant across the strip. However, for the density of chain ends, such a constant behavior seems to occur for both models, unlike the power law observed for flexible polymers. In the regime where the bulk persistence length ?p is comparable to D, hairpin conformations are detected, and the chain linear dimensions are discussed in terms of a crossover from the Daoud/De Gennes "string of blobs"-picture to the flexible rod picture when D decreases and/or the chain stiffness increases. Introducing a suitable further coarse-graining of the chain contours of the continuum model, direct estimates for the deflection length and its distribution could be obtained.

  8. Exact solution of the one-dimensional super-symmetric t-J model with unparallel boundary fields

    NASA Astrophysics Data System (ADS)

    Zhang, Xin; Cao, Junpeng; Yang, Wen-Li; Shi, Kangjie; Wang, Yupeng

    2014-04-01

    The exact solution of the one-dimensional super-symmetric t-J model under generic integrable boundary conditions is obtained via the Bethe ansatz methods. With the coordinate Bethe ansatz, the corresponding R-matrix and K-matrices are derived for the second eigenvalue problem associated with spin degrees of freedom. It is found that the second eigenvalue problem can be transformed into that of the transfer matrix of the inhomogeneous XXX spin chain, which allows us to obtain the spectrum of the Hamiltonian and the associated Bethe ansatz equations by the off-diagonal Bethe ansatz method.

  9. Syntheses, structures and properties of four 3D microporous lanthanide coordination polymers based on 3,5-pyrazoledicarboxylate and oxalate ligands

    SciTech Connect

    Song, Juan; Wang, Ji-Jiang; Hu, Huai-Ming; Wu, Qing-Ran; Xie, Juan; Dong, Fa-Xin; Yang, Meng-Lin; Xue, Gang-Lin

    2014-04-01

    Four three-dimensional lanthanide coordination polymers with reversible structural interconversions, [Ln{sub 2}(Hpdc){sub 2}(C{sub 2}O{sub 4})(H{sub 2}O){sub 4}]{sub n}·2nH{sub 2}O [Ln=Sm (1), Eu (2), Tb (3) and Dy (4)], have been synthesized by hydrothermal reactions of lanthanide nitrates with 3,5-pyrazoledicarboxylic (H{sub 3}pdc) and oxalic acids. It is noteworthy that there is an in situ reaction in 1, in which H{sub 3}pdc was decomposed into (ox){sup 2?} with Cu(II)–Sm(III) synergistic effect under hydrothermal conditions. These compounds are isostructural and crystallized in the monoclinic P2{sub 1}/c space group. The Ln(III) ions are eight-coordinated with dodecahedron coordination geometry. These polyhedra are linked by oxalate groups to form 1D zigzag chain, which are further connected by 3,5-pyrazoledicarboxylate to extend similar 3D frameworks with channels along c-axis in 1–4. These coordination polymers display the characteristic emission bands of the Ln(III) ions in the solid state and possess good thermal stabilities. - Graphical abstract: Four 3D microporous lanthanide coordination polymers with reversible structural interconversion have been synthesized. They exhibit characteristic emission bands of the lanthanide ions and possess great thermal stability. - Highlights: • Four lanthanide coordination polymers have been hydrothermal synthesized. • There is an in situ reaction in 1 in which H{sub 3}pdc was decomposed into (ox){sup 2?} with the Cu(II)–Sm(III) synergistic effect under hydrothermal conditions. • TGA and XRD studies reveal that upon hydration–dehydration, compounds 1–4 undergo a reversible structural interconversion process through a cooling-heating cycle. • Compounds 1–4 exhibit characteristic lanthanide-centered luminescence.

  10. Temperature-induced crossovers in the static roughness of a one-dimensional interface

    NASA Astrophysics Data System (ADS)

    Agoritsas, Elisabeth; Lecomte, Vivien; Giamarchi, Thierry

    2011-03-01

    At finite temperature and in presence of disorder, a one-dimensional elastic interface displays different scaling regimes at small and large lengthscales. Using a replica approach and a Gaussian variational method (GVM), we explore the consequences of a finite interface width ? on its small-lengthscale geometrical fluctuations. We compute analytically the static roughness B (r) of the interface as a function of the distance r between two points on the interface, in the specific case of short-range elasticity and random-bond disorder. We find that for a finite ? two temperature regimes exist, and we determine the corresponding different roughness regimes and their crossover lengthscales. In addition, using a directed polymer description, we study via a second GVM procedure and generic scaling arguments, a modified toy model that provides further insight on those results, which apply to experimental interfaces such as e.g. ferromagnetic domain walls in thin films, subjected to a quenched uncorrelated disorder. This work was supported in part by the Swiss SNF under MaNEP and division II.

  11. One-dimensional transient analysis of volumetric heating for laser drilling

    SciTech Connect

    Zhang Chong; Salama, Islam A.; Quick, Nathaniel R.; Kar, Aravinda

    2006-06-01

    Generally laser energy is considered to interact only with the substrate surface, as in metals, where the laser beam does not propagate into the substrate beyond a very small absorption depth. There are, however, many instances, particularly for ceramics and polymers, where the laser beam can penetrate into the substrate to substantial depths depending on the laser wavelength and laser-material interaction characteristics. Specifically there are polymeric dielectrics used as multilayer electronic substrates in which a laser beam of wavelength 9.3 {mu}m can penetrate into the substrate. The laser energy interacts at the substrate surface as well as inside the substrate. This particular aspect of laser-material interactions is important in laser drilling of blind microvias in polymeric multilayer electronic substrates. A one-dimensional transient heat conduction model including vaporization parameters is constructed to analyze this behavior. The absorption coefficient of the dielectric is also considered in this model and the problem is solved analytically. The microvia drilling speed, temperature distribution in the dielectric, and the thickness of the residue along the microvia walls and at the bottom of the microvia are studied for different laser irradiation conditions. An overheated metastable state of material is found to exist inside the workpiece. The overheating parameters are calculated for various laser drilling parameters and are used to predict the onset of thermal damage and to minimize the residue.

  12. Structure and spectroscopic properties of a three-dimensional PbII coordination polymer constructed from 1,1?-biphenyl-2,2?,4,4?-tetracarboxylate

    NASA Astrophysics Data System (ADS)

    Su, Feng; Lu, Liping; Feng, Sisi

    2015-09-01

    The title coordination polymer, poly[aqua(?8-1,1?-biphenyl-2,2?,4,4?-tetracarboxylate)lead(II)], [Pb2(C16H6O8)(H2O)2]n, (I), was constructed by a multidentate ligand 1,1?-biphenyl-2,2?,4,4?-tetra- carboxylic acid (abbreviated as H4bpta) under hydrothermal condition. In the structure, two crystallographically independent Pb(II) cations exhibit different coordination geometries, wherein one of the Pb(II) ions is holodirected and coordinated by eight oxygen atoms [PbO8] and another chelated by carboxylates, is slightly hemidirected and coordinated by seven oxygen atoms [PbO7] [1]. The bpta4- ligand connects eight Pb(II) atoms by adopting the ?8-bridging mode. The carboxylate groups (2,2?-COO-) are in ?4-?1:?2:?2:?2-chelating/bridging, and the other two (4,4?-COO-) are in ?4-?1:?2:?1:?2 fashion. In addition, the structure of (I) consists of 1D chains built by carboxylate groups bridging a pair of quad-core cluster [Pb4O4] units, which is further linked through bpta4- to generate a unique 3D open framework. The coordination polymer is reinforced by intermolecular hydrogen bonding between oxygen atoms of the carboxylate groups, and coordination water molecules. The complex has also been characterized by PXRD, thermoanalysis, and luminescence.

  13. Three NEW butane-1,2,3,4-tetracarboxylato-bridged coordination polymers: Syntheses, crystal structures and charaterization

    NASA Astrophysics Data System (ADS)

    Zhu, Hong-Lin; Zheng, Yue-Qing

    2010-04-01

    Three new butane-1,2,3,4-tetracarboxylato bridged coordination polymers [Zn 2(H 2O) 4(BTC)]·3H 2O 1, [Cd 2(H 2O) 4(BTC)]·2H 2O 2 and [Y 2(H 2O) 6(H 2BTC)(BTC)]·5H 2O 3 (H 4BTC = butane-1,2,3,4-tetracarboxylic acid) were synthesized and characterized by IR spectroscopy, TG-DTA analyses, elemental analyses and single-crystal X-ray diffraction, and their fluorescence properties were also investigated. In 1, the trigonal pyramidally coordinated Zn atoms are brigded by both ? 6? 6 and ? 6? 8 centrosymmetric BTC 4- anions into 2D layers, which are connected by the octahedrally coordinated Zn atoms to build up 3D (4 4·6 10·8)(4 4·6 2) 2(4 4·6 8·8 2·10) topological framework with the lattice water molecules in cavities. In 2, the CdO 7 pentagonal bipyramids and the CdO 8 4,4'-bicapped triagonal antiprisms are edge-shared to generate the Cd 2O 13 bipolyhedra, which are further corner-shared into 1D metal-oxide chains. The resulting chains are interconnected by the ? 6? 8 BTC 4- anion to form 2D (4 3) 2(4 6·6 6·8 3) networks, which are assembled via interlayer hydrogen bonds into a 3D (4 11·6 11·8 6)(4 3)(4 9·6) topological supramolecular architecture with the lattice H 2O molecules located in holes. The distorted 4,4'-bicapped triagonal antiprismatically coordinated Y atoms in 3 are interconnected ? 4? 4 H 2BTC 2- and ?4? 6 BTC 4- anions to from 2D (4 4·6 2) topological networks, which are held together via strong interlayer hydrogen bonds into a 3D fsc topological supramolecular architecture with the lattice water molecules residing in cavities.

  14. Assembling supramolecular networks by halogen bonding in coordination polymers driven by 5-bromonicotinic acid

    SciTech Connect

    Gu, Jin-Zhong; Wu, Jiang; Kirillov, Alexander M.; Lv, Dong-Yu; Tang, Yu; Wu, Jin-Cai

    2014-05-01

    A series of six coordination compounds ([Zn(5-Brnic){sub 2}]·1.5H{sub 2}O){sub n} (1), [Cd(5-Brnic){sub 2}]{sub n} (2), [Co(5-Brnic){sub 2}(H{sub 2}O){sub 2}]{sub n} (3), [Zn(5-Brnic){sub 2}(H{sub 2}biim)]{sub n} (4), ([Cd(5-Brnic){sub 2}(phen)]·H{sub 2}O){sub n} (5), and [Pb(5-Brnic){sub 2}(phen)] (6) have been generated by the hydrothermal method from the metal(II) nitrates, 5-bromonicotinic acid (5-BrnicH), and an optional ancillary 1,10-phenanthroline (phen) or 2,2?-biimidazole (H{sub 2}biim) ligand. All the products 1–6 have been characterized by IR spectroscopy, elemental, thermal, powder and single-crystal X-ray diffraction analyses. Their 5-bromonicotinate-driven structures vary from the 3D metal-organic framework with the seh-3,5-P21/c topology (in 2) and the 2D interdigitated layers with the sql topology (in 1 and 3), to the 1D chains (in 4 and 5) and the 0D discrete monomers (in 6). The 5-bromonicotinate moiety acts as a versatile building block and its tethered bromine atom plays a key role in reinforcing and extending the structures into diverse 3D supramolecular networks via the various halogen bonding Br?O, Br?Br, and Br?? interactions, as well as the N–H?O and C–H?O hydrogen bonds. The obtained results demonstrate a useful guideline toward engineering the supramolecular architectures in the coordination network assembly under the influence of various halogen bonding interactions. The luminescent (for 1, 2, 4, 5, and 6) and magnetic (for 3) properties have also been studied and discussed in detail. - Graphical abstract: Six coordination compounds driven by 5-bromonicotinic acid have been generated and structurally characterized, revealing diverse metal-organic networks that are further reinforced and extended via various halogen bonding interactions. - Highlights: • 5-Bromonicotinic acid is a versatile ligand for Zn, Cd, Co and Pb derivatives. • Careful selection of co-ligands and metals resulted in different network structures. • Halogen and hydrogen bonding interactions lead to various supramolecular networks. • Luminescent and magnetic properties were studied and discussed in detail.

  15. Structural characterization, electrochemical, photoluminescence and thermal properties of potassium ion-mediated coordination polymer

    NASA Astrophysics Data System (ADS)

    Ceyhan, Gökhan; Köse, Muhammet; Tümer, Mehmet; Dal, Hakan

    2015-05-01

    A polymeric potassium complex of p-nitrophenol was synthesized and characterized by analytical and spectroscopic techniques. Molecular structure of the complex was determined by single crystal X-ray diffraction study. X-ray structural data show that crystals contain polymeric K+ complex of p-nitrophenol. Asymmetric unit consists of one p-nitrophenolate, one K+ ion and one water molecule. All bond lengths and angles in the phenyl rings have normal Csp2-Csp2 values and are in the expected ranges. The p-nitrophenolate is close to planar with small distortions by some atoms. Each potassium ion in the polymeric structure is identical and eight-coordinate, bonded to four nitro, two phenolate oxygen atoms from five p-nitrophenolate ligands and two oxygen atoms from two water molecules. Electronic, electrochemical, photoluminescence and thermal properties of the complex were also investigated.

  16. Structural characterization, electrochemical, photoluminescence and thermal properties of potassium ion-mediated coordination polymer.

    PubMed

    Ceyhan, Gökhan; Köse, Muhammet; Tümer, Mehmet; Dal, Hakan

    2015-05-01

    A polymeric potassium complex of p-nitrophenol was synthesized and characterized by analytical and spectroscopic techniques. Molecular structure of the complex was determined by single crystal X-ray diffraction study. X-ray structural data show that crystals contain polymeric K(+) complex of p-nitrophenol. Asymmetric unit consists of one p-nitrophenolate, one K(+) ion and one water molecule. All bond lengths and angles in the phenyl rings have normal Csp2-Csp2 values and are in the expected ranges. The p-nitrophenolate is close to planar with small distortions by some atoms. Each potassium ion in the polymeric structure is identical and eight-coordinate, bonded to four nitro, two phenolate oxygen atoms from five p-nitrophenolate ligands and two oxygen atoms from two water molecules. Electronic, electrochemical, photoluminescence and thermal properties of the complex were also investigated. PMID:25698438

  17. Assembling supramolecular networks by halogen bonding in coordination polymers driven by 5-bromonicotinic acid

    NASA Astrophysics Data System (ADS)

    Gu, Jin-Zhong; Wu, Jiang; Kirillov, Alexander M.; Lv, Dong-Yu; Tang, Yu; Wu, Jin-Cai

    2014-05-01

    A series of six coordination compounds {[Zn(5-Brnic)2]·1.5H2O}n (1), [Cd(5-Brnic)2]n (2), [Co(5-Brnic)2(H2O)2]n (3), [Zn(5-Brnic)2(H2biim)]n (4), {[Cd(5-Brnic)2(phen)]·H2O}n (5), and [Pb(5-Brnic)2(phen)] (6) have been generated by the hydrothermal method from the metal(II) nitrates, 5-bromonicotinic acid (5-BrnicH), and an optional ancillary 1,10-phenanthroline (phen) or 2,2?-biimidazole (H2biim) ligand. All the products 1-6 have been characterized by IR spectroscopy, elemental, thermal, powder and single-crystal X-ray diffraction analyses. Their 5-bromonicotinate-driven structures vary from the 3D metal-organic framework with the seh-3,5-P21/c topology (in 2) and the 2D interdigitated layers with the sql topology (in 1 and 3), to the 1D chains (in 4 and 5) and the 0D discrete monomers (in 6). The 5-bromonicotinate moiety acts as a versatile building block and its tethered bromine atom plays a key role in reinforcing and extending the structures into diverse 3D supramolecular networks via the various halogen bonding Br⋯O, Br⋯Br, and Br⋯? interactions, as well as the N-H⋯O and C-H⋯O hydrogen bonds. The obtained results demonstrate a useful guideline toward engineering the supramolecular architectures in the coordination network assembly under the influence of various halogen bonding interactions. The luminescent (for 1, 2, 4, 5, and 6) and magnetic (for 3) properties have also been studied and discussed in detail.

  18. Ground states of dipolar gases in quasi-one-dimensional ring traps

    SciTech Connect

    Zoellner, Sascha

    2011-12-15

    We compute the ground state of dipoles in a quasi-one-dimensional ring trap using few-body techniques combined with analytical arguments. The effective interaction between two dipoles depends on their center-of-mass coordinate and can be tuned by varying the angle between dipoles and the plane of the ring. For sufficiently weak interactions, the state resembles a weakly interacting Fermi gas or a (inhomogeneous) Lieb-Liniger gas. A mapping between the Lieb-Liniger-gas parameters and the dipolar-gas parameters in and beyond the Born approximation is established, and we discuss the effect of inhomogeneities based on a local-density approximation. For strongly repulsive interactions, the system exhibits a crystal-like localization of the particles. Their inhomogeneous distribution may be understood in terms of a simple few-body model as well as a local-density approximation. In the case of partially attractive interactions, clustered states form for sufficiently strong coupling, and the dependence of the state on particle number and orientation angle of the dipoles is discussed analytically.

  19. Simulation of one-dimensional evolution of wind waves in a deep water

    NASA Astrophysics Data System (ADS)

    Chalikov, Dmitry; Babanin, Alexander V.

    2014-09-01

    A direct wave model based on the one-dimensional nonlinear equations for potential waves is used for simulation of wave field development under the action of energy input, dissipation, and nonlinear wave-wave interaction. The equations are written in conformal surface-fitted nonstationary coordinate system. New schemes for calculating the input and dissipation of wave energy are implemented. The wind input is calculated on the basis of the parameterization developed through the coupled modeling of waves and turbulent boundary layer. The wave dissipation algorithm, introduced to prevent wave breaking instability, is based on highly selective smoothing of the wave surface and surface potential. The integration is performed in Fourier domain with the number of modes M = 2048, broad enough to reproduce the energy downshifting. As the initial conditions, the wave field is assigned as train of Stokes waves with steepness ak = 0.15 at nondimensional wavenumber k = 512. Under the action of nonlinearity and energy input the spectrum starts to grow. This growth is followed by the downshifting. The total time of integration is equal to 7203 initial wave periods. During this time the energy increased by 1111 times. Peak of the spectrum gradually shifts from wavenumber nondimensional k = 512 down to k = 10. Significant wave height increases 33 times, while the peak period increases 51 times. Rates of the peak downshift and wave energy evolution are in good agreement with the JONSWAP formulation.

  20. Impenetrable Mass-Imbalanced Particles in One-Dimensional Harmonic Traps

    E-print Network

    A. S. Dehkharghani; A. G. Volosniev; N. T. Zinner

    2015-11-05

    Strongly interacting particles in one dimension subject to external confinement have become a topic of considerable interest due to recent experimental advances and the development of new theoretical methods to attack such systems. In the case of equal mass fermions or bosons with two or more internal degrees of freedom, one can map the problem onto the well-known Heisenberg spin models. However, many interesting physical systems contain mixtures of particles with different masses. Therefore, a generalization of the recent strong-coupling techniques would be highly desirable. This is particularly important since such problems are generally considered non-integrable and thus the hugely successful Bethe ansatz approach cannot be applied. Here we discuss some initial steps towards this goal by investigating small ensembles of one-dimensional harmonically trapped particles where pairwise interactions are either vanishing or infinitely strong with focus on the mass-imbalanced case. We discuss a possible (semi)-analytical approach to describe systems using hyperspherical coordinates where the interaction is effectively decoupled from the trapping potential. As an illustrative example we analyze mass-imbalanced four-particle two-species mixtures with strong interactions between the two species. For such systems we calculate the energies, densities and pair-correlation functions.

  1. In the Bottlebrush Garden: The Structural Aspects of Coordination Polymer Phases formed in Lanthanide Extraction with Alkyl Phosphoric Acids.

    PubMed

    Ellis, Ross J; Demars, Thomas; Liu, Guokui; Niklas, Jens; Poluektov, Oleg G; Shkrob, Ilya A

    2015-09-01

    Coordination polymers (CPs) of metal ions are central to a large variety of applications, such as catalysis and separations. These polymers frequently occur as amorphous solids that segregate from solution. The structural aspects of this segregation remain elusive due to the dearth of the spectroscopic techniques and computational approaches suitable for probing such systems. Therefore, there is a lacking of understanding of how the molecular building blocks give rise to the mesoscale architectures that characterize CP materials. In this study we revisit a CP phase formed in the extraction of trivalent lanthanide ions by diesters of the phosphoric acid, such as the bis(2-ethylhexyl)phosphoric acid (HDEHP). This is a well-known system with practical importance in strategic metals refining and nuclear fuel reprocessing. A CP phase, referred to as a "third phase", has been known to form in these systems for half a century, yet the structure of the amorphous solid is still a point of contention, illustrating the difficulties faced in characterizing such materials. In this study, we follow a deductive approach to solving the molecular structure of amorphous CP phases, using semiempirical calculations to set up an array of physically plausible models and then deploying a suite of experimental techniques, including optical, magnetic resonance, and X-ray spectroscopies, to consecutively eliminate all but one model. We demonstrate that the "third phase" consists of hexagonally packed linear chains in which the lanthanide ions are connected by three O-P-O bridges, with the modifying groups protruding outward, as in a bottlebrush. The tendency to yield linear polynuclear oligomers that is apparent in this system may also be present in other systems yielding the "third phase", demonstrating how molecular geometry directs polymeric assembly in hybrid materials. We show that the packing of bridging molecules is central to directing the structure of CP phases and that by manipulating the steric requirements of ancillary groups one can control the structure of the assembly. PMID:26244450

  2. Mixed alkali metal/transition metal coordination polymers with the mellitic acid hexaanion: 2-dimensional hexagonal magnetic nets.

    PubMed

    Humphrey, Simon M; Mole, Richard A; Thompson, Richard I; Wood, Paul T

    2010-04-01

    The hexaanion of mellitic acid, mel = (C(6)(CO(2))(6))(6-), links metal ions into extensively connected magnetic coordination polymers. Reaction of alkali metal mellitate salts, M(6)(mel) (M = K, Rb), with M'Cl(2) precursors (M' = Mn, Co, Ni) under mild (473 K) hydrothermal conditions yields an extensive family of isostructural 3-dimensional mixed alkali metal/transition metal polymers of general formula M(2)[M'(2)(mel)(OH(2))(2)] (M/M' = K/Mn (1a); K/Co (1b); K/Ni (1c); Rb/Mn (2a); Rb/Co (2b); Rb/Ni (2c)). These materials incorporate distorted 2-dimensional magnetic hexagonal nets with a honeycomb topology that are exclusively based on metal-carboxylate-metal bridging interactions. A further isostructural alkali metal-free Co(2+) material with NH(4)(+) cations, (NH(4))(2)[Co(2)(mel)(OH(2))(2)] (3), produced by reaction of H(6)mel with [Co(NH(3))(6)]Cl(3) is also presented. The magnetic susceptibility data for 1a-c, 2a-c, and 3 are presented. The susceptibility data for the Mn(II)- and Ni(II)-containing phases have been analyzed using a simple Mean Field Theory approach, and have been modeled using a high temperature series expansion. The comparative magnetism of the Co(II) phases is also presented, and is more complicated because of significant spin-orbit coupling effects. PMID:20205381

  3. Influence of the steric effect of flexible isomeric phenylenediacetic acids on the resultant lead(II) coordination polymers

    NASA Astrophysics Data System (ADS)

    Wu, Yunlong; Zhao, Yanqing; Yang, Guo-Ping; Guo, Yanjun; Wang, Yao-Yu; Shi, Qi-Zhen

    2015-03-01

    To study the steric effect of the flexible dicarboxylate ligands on the resultant formations of coordination polymers (CPs), four new PbII CPs [Pb(1,2-pda)(H2O)]n (1), [Pb(1,3-pda)]n·nH2O (2), [Pb2(1,4-pda)2(H2O)]n·2nH2O (3a and 3b) have been produced by the isomeric phenylenediacetic acids (H2pda). The X-ray crystallography study reveals that CP 1 is a two-dimensional (2D) 4-connected sql (44.62) network via the weak Pb···O interactions built on 1D chain-like structure. CP 2 crystallizes in orthorhombic system with chiral space group P212121, showing a 4-connected sra (42.63.8) framework where a left-handed helical motif is formed by PbII ions and trans-1,3-pda ligands. More interestingly, CPs 3a and 3b are two true 3D polymorphs and have the different morphology. Topologically, the framework of 3a exhibits a 4-connected lon 66 motif, while that of 3b is a (4,6)-connected fsh (43.63)2(46.66.83) net. It is found that the three isomeric pda anions display the various coordination fashions in four CPs. The different structural arrangements show that the steric effect of the isomeric H2pda tectons has a positive role in directing the final products of PbII CPs. Also, the fluorescent properties of the CPs were studied in the solid state at room temperature.

  4. Lanthanide Coordination Polymers with 4,4'-Azobenzoic Acid: Enhanced Stability and Magnetocaloric Effect by Removing Guest Solvents.

    PubMed

    Zhang, Shaowei; Duan, Eryue; Han, Zongsu; Li, Leilei; Cheng, Peng

    2015-07-01

    Three lanthanide coordination polymers (Ln-CPs) formulated as [Ln(azdc)(HCOO)]n [Ln = Gd(III) (1), Tb(III) (2), Dy(III) (3); H2azdc = 4,4'-azobenzoic acid] have been successfully obtained by the solvothermal reaction of Ln(III) ions with H2azdc ligands in the mixed solvent N,N-dimethylformamide (DMF)/H2O. Compared with our previous work on Ln-CPs with H2azdc ligands, [Gd2(azdc)3(DMA)2]n·2nDMA (1'; DMA = dimethylacetamide), in which the DMA molecules coordinate to Gd(III) ions that are replaced by HCOO(-) groups in 1, resulting in the distinct structures and properties of the final products. Adjacent Ln(III) ions in 1-3 are connected by HCOO(-) groups through bridging and chelating modes to give 2D layers, which are further linked by azdc(2-) ligands to produce 3D frameworks. Magnetic results declare that antiferromagnetic couplings exist in 1, although two different magnetic interactions among adjacent Gd(III) ions derived from antiferromagnetic interactions of the smaller Gd-O-Gd angles (Gd···Gd distances) and weak ferromagnetic interactions of the larger Gd-O-Gd angles (Gd···Gd distances) coexist in 1. Furthermore, the magnetocaloric effect (MCE) value of 1 is 1.5 times as large as that of 1'. More importantly, 1 exhibits excellent stabilities toward air, thermal, solvent, and acid/alkaline conditions. The results manifest that the crystalline structure of 1 can be stable at at least 425 °C supported by the in situ variable-temperature powder X-ray diffraction patterns and thermogravimetric analyses, in air for at least 3 months, and in common solvents for more than 1 week, as well as in aqueous solutions ranging from pH = 2 to 12 for more than 1 week. PMID:26097991

  5. Uranyl sensitization of samarium (III) luminescence in a two-dimensional coordination polymer

    SciTech Connect

    Knope, Karah E.; de Lill, Daniel T.; Rowland, Clare E.; Cantos, Paula M.; de Bettencourt-Dias, Ana; Cahill, Christopher L.

    2012-01-02

    Heterometallic carboxyphosphonates UO?2+/Ln3+ have been prepared from the hydrothermal reaction of uranyl nitrate, lanthanide nitrate (Ln = Sm, Tb, Er, Yb), and phosphonoacetic acid (H?PPA). Compound 1, (UO?)?(PPA)(HPPA)?Sm(H?O)·2H?O (1) adopts a two-dimensional structure in which the UO?2+ metal ions bind exclusively to the phosphonate moiety, whereas the Ln3+ ions are coordinated by both phosphonate and carboxylate functionalities. Luminescence studies of 1 show very bright visible and near-IR samarium(III)-centered emission upon direct excitation of the uranyl moiety. The Sm3+ emissive state exhibits a double-exponential decay with lifetimes of 67.2 ± 6.5 and 9.0 ± 1.3 ?s as measured at 594 nm, after excitation at both 365 and 420 nm. No emission is observed in the region typical of the uranyl cation, indicating that all energy is either transferred to the Sm3+ center or lost to nonradiative processes. Herein we report the synthesis, crystal structure, and luminescent behavior of 1, as well as those of the isostructural terbium, erbium, and ytterbium analogues.

  6. Structural Vibration for Robotic Communication and Sensing on One-Dimensional Structures

    E-print Network

    White, Robert D.

    Structural Vibration for Robotic Communication and Sensing on One-Dimensional Structures Maxwell-borne vibrations in a one- dimensional structure are examined as a means of communica- tion and sensing for networks of robots. The concept is inspired by the observation that insects may use structural vibrations

  7. SYSTEMS OF ONE-DIMENSIONAL RANDOM WALKS IN A COMMON RANDOM ENVIRONMENT

    E-print Network

    Peterson, Jonathon

    SYSTEMS OF ONE-DIMENSIONAL RANDOM WALKS IN A COMMON RANDOM ENVIRONMENT JONATHON PETERSON Abstract. We consider a system of independent one-dimensional random walks in a common random environment under-dimensional random walks in a common random environment. We modify the standard notion of random walks in random

  8. Entanglement and Quantum Phase Transition in a One-Dimensional System of quantum Dots with Disorder

    E-print Network

    Kais, Sabre

    Entanglement and Quantum Phase Transition in a One-Dimensional System of quantum Dots with Disorder We study the entanglement of formation and quantum phase transition in a one-dimensional quantum dots, for certain parameters, the entanglement is negligible up to a critical point Uc, where a quantum phase

  9. Numerical analysis of a one-dimensional elastodynamic model of dry friction and unilateral contact

    E-print Network

    Renard, Yves - Pôle de Mathématiques, Institut National des Sciences Appliquées de Lyon

    , France Abstract This paper deals with a numerical analysis of a one-dimensional dynamic purely elastic (i fundamental properties of the dynamic behavior of elastic structure under dry friction and unilateral contact #12;2. The one-dimensional elastic model with dry friction The model we deal with in this paper

  10. ONE DIMENSIONAL MARKOV RANDOM FIELDS, MARKOV CHAINS AND TOPOLOGICAL MARKOV FIELDS

    E-print Network

    Pavlov, Ronnie

    ONE DIMENSIONAL MARKOV RANDOM FIELDS, MARKOV CHAINS AND TOPOLOGICAL MARKOV FIELDS Nishant. Introduction A one-dimensional Markov chain is defined by a one-sided, directional conditional independence property, and a process is Markov in the forward direction if and only if it is Markov in the backward

  11. New Insights from One-Dimensional Spin Helmut G. Katzgraber1

    E-print Network

    Peinke, Joachim

    New Insights from One-Dimensional Spin Glasses Helmut G. Katzgraber1 , Alexander K. Hartmann2- range spin-glass models. The one-dimensional spin glass with random power-law interactions promises-Kirkpatrick (SK) spin glass. Unfortunately, an analytical solution for short-range realistic spin-glass models

  12. Thermal Conductivity of One-Dimensional Lattices with Self-Consistent Heat Baths

    E-print Network

    Li, Baowen

    Thermal Conductivity of One-Dimensional Lattices with Self-Consistent Heat Baths: A Heuristic and breathers. KEYWORDS: heat conduction, classical transport, Langevin dynamics DOI: 10.1143/JPSJ.78.044001 1. Introduction Heat conduction exhibits diversified behaviors for one- dimensional lattices in terms of heat

  13. Correlations and scaling in one-dimensional heat conduction J. M. Deutsch and Onuttom Narayan

    E-print Network

    Deutsch, Josh

    Correlations and scaling in one-dimensional heat conduction J. M. Deutsch and Onuttom Narayan of the heat current, through the Kubo formula, gives a thermal conductivity exponent of 1/3 in agreement.40.Mg I. INTRODUCTION Heat conduction in one-dimensional systems is a simple example of the general

  14. Atomically precise self-assembly of one-dimensional structures on silicon

    E-print Network

    Himpsel, Franz J.

    Atomically precise self-assembly of one-dimensional structures on silicon I. Barke, T.K. Ru-magnetic surface. An interesting by-product is a memory structure with self-assembled tracks that are five atom: Low-dimensional structures; Atomic wires; Silicon surfaces; One-dimensional physics; Scanning

  15. Spin-selective Peierls transition in interacting one-dimensional conductors with spin-orbit interaction

    E-print Network

    Braunecker, Bernd

    Spin-selective Peierls transition in interacting one-dimensional conductors with spin Tbilisi, Georgia Received 7 July 2010; published 29 July 2010 Interacting one-dimensional conductors of low-dimensional elec- tron conductors. They lead to interesting correlated-electron physics but also

  16. One-Dimensional ZnO Nanostructures: Solution Growth and Functional Properties

    E-print Network

    Wang, Zhong L.

    and versatile technique for growing 1D ZnO nanostructures. Here in this review, we focus on the 1D ZnO nanoNano Res 1 One-Dimensional ZnO Nanostructures: Solution Growth and Functional Properties Sheng Xu University Press and Springer-Verlag Berlin Heidelberg 2011 ABSTRACT One-dimensional (1D) ZnO nanostructures

  17. The rigged Hilbert space of the algebra of the one-dimensional rectangular barrier potential

    NASA Astrophysics Data System (ADS)

    de la Madrid, Rafael

    2004-08-01

    The rigged Hilbert space of the algebra of the one-dimensional rectangular barrier potential is constructed. The one-dimensional rectangular potential provides another opportunity to show that the rigged Hilbert space fully accounts for Dirac's bra-ket formalism. The analogy between Dirac's formalism and Fourier methods is pointed out.

  18. A Cutting Plane Algorithm for the One-Dimensional Cutting Stock Problem with Multiple Stock Lengths

    E-print Network

    Scheithauer, Guntram.

    A Cutting Plane Algorithm for the One-Dimensional Cutting Stock Problem with Multiple Stock Lengths with column generation is generalized for the case of multiple stock lengths in the one-dimensional cutting stock problem. Appropriate modi#12;cations of the column generation procedure and the rounding heuristic

  19. Parameter-dependent thermal conductivity of one-dimensional 4 Nianbei Li1

    E-print Network

    Li, Baowen

    Parameter-dependent thermal conductivity of one-dimensional 4 lattice Nianbei Li1 and Baowen Li1 the thermal conductivity of a one-dimensional 4 lattice with strong on-site harmonic potential. The expression for the thermal conductivity in terms of different parameters is derived from the effective phonon theory

  20. Sonochemical synthesis of a new nano-sized cerium(III) coordination polymer and its conversion to nanoceria.

    PubMed

    Derakhshandeh, Parviz Gohari; Soleimannejad, Janet; Janczak, Jan

    2015-09-01

    Nanoparticles of a new two-dimensional cerium(III) coordination polymer compound, [Ce(pzdc)(pzdcH)(H2O)3]n (1), (H2pzdc=2,3-pyrazinedicarboxylic acid), have been synthesized by a sonochemical process and characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRPD), FT-IR spectroscopy and elemental analyses. Compound 1 was structurally characterized by single crystal X-ray diffraction and was shown that it consists of 2D sheets that construct a three-dimensional supramolecular architecture via non-covalent interactions i.e. hydrogen bonding. The thermal stability of compound 1 both for its crystals and nanostructures has been studied by the thermal gravimetric (TG) method and compared with each other. The role of ultrasound irradiation power and the concentration of initial reactants on the size and morphology of the nano-structured compound 1, has been investigated. Calcination of compound 1 at 800°C under air atmosphere yields ceria nanoparticles. Furthermore, the fluorescent properties of compound 1 at room temperature were studied. PMID:25682466

  1. Synthesis, crystal structures, luminescence and catalytic properties of two d10 metal coordination polymers constructed from mixed ligands

    NASA Astrophysics Data System (ADS)

    Wang, Xiao-xiao; Zhang, Ming-xi; Yu, Baoyi; Van Hecke, Kristof; Cui, Guang-hua

    2015-03-01

    Two new coordination polymers [Cd(bmb)(hmph)]n (1), {[Ag(bmb)]·H2btc}n (2) (bmb = 1,4-bis(2-methylbenzimidazol-1-ylmethyl)benzene, H2hmph = homophthalic acid, H3btc = 1,3,5-benzenetetracarboxylic acid) were synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction methods, IR spectroscopy, TGA, XRPD and elemental analysis. Complex 1 features a 3D threefold interpenetrating dia array with a 4-connected 66 topology. Complex 2 shows a 1D helix chain structure connected by L1 ligands, which is finally extended into a rarely 2D 4L2 supramolecular network via C-H⋯O hydrogen bond interactions. In addition, the luminescence and catalytic properties of the two complexes for the degradation of the methyl orange azo dye in a Fenton-like process were presented. The degradation efficiency of the methyl orange azo dye for 1 and 2 are 56% and 96%, respectively.

  2. Assembly of three new POM-based Ag(I) coordination polymers with antibacterial and photocatalytic properties

    NASA Astrophysics Data System (ADS)

    Lu, Xin-Xin; Luo, Yu-Hui; Lu, Chen; Chen, Xin; Zhang, Hong

    2015-12-01

    Three new silver coordination polymers, namely, {Ag3(bpy)6[PW12O40]} (1), {Ag5(H2biim)2(Hbiim-NO2)2[PW12O40]} (2), {Ag7(pytz)4[PW12O40]} (3) (bpy=2,2?-bipyridine, H2biim=2,2?-biimidazole, pytz=4-(1H-tetrazol-5-yl)pyridine), have been synthesized under hydrothermal condition. Compound 1 shows a 3D supramolecular framework based on 0D moieties. Compound 2 exhibits an attractive 2D biologic screw axis. Compound 3 displays a 3D structure, which consists of Ag(I)···? interactions, ?···? stacking and weak Ag···Ag interactions. It is noteworthy that nitration happens to compound 2 during the hydrothermal condition, which is quite rare. Through contrasting the antibacterial activities of gram negative and gram positive bacteria, we find compounds 1-3 have better antibacterial property in gram negative bacteria than gram positive bacteria. In addition, compounds 1-3 also exhibit efficiency of photocatalytic decomposition of organic dyes. Those compounds may be used as potential multifunctional materials in wastewater treatment, because they not only can kill bacteria but also degrade organic pollutants.

  3. Manganese-based layered coordination polymer: synthesis, structural characterization, magnetic property, and electrochemical performance in lithium-ion batteries.

    PubMed

    Liu, Qi; Yu, Lili; Wang, Ying; Ji, Yunzhou; Horvat, Josip; Cheng, Mei-Ling; Jia, Xiaoyan; Wang, Guoxiu

    2013-03-18

    Manganese-based layered coordination polymer ([Mn(tfbdc)(4,4'-bpy)(H2O)2], Mn-LCP) with microporous structure was synthesized by reaction of 2,3,5,6-tetrafluoroterephthalatic acid(H2tfbdc) and 4,4'-bipyridine(4,4'-bpy) with manganese(II) acetate tetrahydrate in water solution. Mn-LCP was characterized by elemental analysis, IR spectra, thermogravimetric analysis, X-ray single-crystal structure analysis, and powder X-ray diffraction. Magnetic susceptibility data from 300 to 1.8K show that there is a weak antiferromagnetic exchange between Mn(II) ions in Mn-LCP. As anode material, the Mn-LCP electrode exhibits an irreversible high capacity in the first discharge process and a reversible lithium storage capacity of up to about 390 mA h/g from the fourth cycle. It might provide a new method for finding new electrode materials in lithium-ion batteries. PMID:23461562

  4. Solvent induced rapid modulation of micro/nano structures of metal carboxylates coordination polymers: mechanism and morphology dependent magnetism

    NASA Astrophysics Data System (ADS)

    Liu, Kun; Shen, Zhu-Rui; Li, Yue; Han, Song-De; Hu, Tong-Liang; Zhang, Da-Shuai; Bu, Xian-He; Ruan, Wen-Juan

    2014-08-01

    Rational modulation of morphology is very important for functional coordination polymers (CPs) micro/nanostructures, and new strategies are still desired to achieve this challenging target. Herein, organic solvents have been established as the capping agents for rapid modulating the growth of metal-carboxylates CPs in organic solvent/water mixtures at ambient conditions. Co-3,5-pyridinedicarboxylate (pydc) CPs was studied here as the example. During the reaction, the organic solvents exhibited three types of modulation effect: anisotropic growth, anisotropic growth/formation of new crystalline phase and the formation of new crystalline phase solely, which was due to the variation of their binding ability with metal cations. The following study revealed that the binding ability was critically affected by their functional groups and molecular size. Moreover, their modulation effect could be finely tuned by changing volume ratios of solvent mixtures. Furthermore, they could be applied for modulating other metal-carboxylates CPs: Co-1,3,5-benzenetricarboxylic (BTC), Zn-pydc and Eu-pydc etc. Additionally, the as-prepared Co-pydc CPs showed a fascinating morphology-dependent antiferromagnetic behavior.

  5. Solvent induced rapid modulation of micro/nano structures of metal carboxylates coordination polymers: mechanism and morphology dependent magnetism

    PubMed Central

    Liu, Kun; Shen, Zhu-Rui; Li, Yue; Han, Song-De; Hu, Tong-Liang; Zhang, Da-Shuai; Bu, Xian-He; Ruan, Wen-Juan

    2014-01-01

    Rational modulation of morphology is very important for functional coordination polymers (CPs) micro/nanostructures, and new strategies are still desired to achieve this challenging target. Herein, organic solvents have been established as the capping agents for rapid modulating the growth of metal-carboxylates CPs in organic solvent/water mixtures at ambient conditions. Co-3,5-pyridinedicarboxylate (pydc) CPs was studied here as the example. During the reaction, the organic solvents exhibited three types of modulation effect: anisotropic growth, anisotropic growth/formation of new crystalline phase and the formation of new crystalline phase solely, which was due to the variation of their binding ability with metal cations. The following study revealed that the binding ability was critically affected by their functional groups and molecular size. Moreover, their modulation effect could be finely tuned by changing volume ratios of solvent mixtures. Furthermore, they could be applied for modulating other metal-carboxylates CPs: Co-1,3,5-benzenetricarboxylic (BTC), Zn-pydc and Eu-pydc etc. Additionally, the as-prepared Co-pydc CPs showed a fascinating morphology-dependent antiferromagnetic behavior. PMID:25113225

  6. Syntheses, structures, molecular and cationic recognitions and catalytic properties of two lanthanide coordination polymers based on a flexible tricarboxylate

    NASA Astrophysics Data System (ADS)

    Zhu, Yu; Wang, Yan-Mei; Xu, Ji; Liu, Pan; Weththasinha, H. A. B. M. D.; Wu, Yun-Long; Lu, Xiao-Qing; Xie, Ji-Min

    2014-11-01

    Two lanthanide coordination polymers, namely, {[La(TTTA)(H2O)2]·2H2O}n (La-TTTA) and [Nd(TTTA)(H2O)2]·2H2O}n (Nd-TTTA) have been hydrothermally synthesized through the reaction of lanthanide ions (La3+ and Nd3+) with the flexible tripodal ligand 2,2?,2?-[1,3,5-triazine-2,4,6-triyltris(thio)]tris-acetic acid (H3TTTA). La-TTTA and Nd-TTTA are isostructural and both show three dimensional structures. La-TTTA and Nd-TTTA show good recognition of amine molecules via quenching the luminescent intensities in amines emulsions. They can also recognize Fe3+, Cu2+, Mg2+, Cr3+ and Co2+ ions with the quenching the peak around 361 nm when the compounds immersed in ionic solutions. The two compounds act as efficient Lewis acid catalysts for the cyanosilylation of benzaldehyde and derivatives in high yields shortly due to the strong Lewis acidity and the possible open sites of the lanthanide ions.

  7. Silver Coordination Polymers for Prevention of Implant Infection: Thiol Interaction, Impact on Respiratory Chain Enzymes, and Hydroxyl Radical Induction? †

    PubMed Central

    Gordon, Oliver; Vig Slenters, Tünde; Brunetto, Priscilla S.; Villaruz, Amer E.; Sturdevant, Daniel E.; Otto, Michael; Landmann, Regine; Fromm, Katharina M.

    2010-01-01

    Prosthetic joint replacements are used increasingly to alleviate pain and improve mobility of the progressively older and more obese population. Implant infection occurs in about 5% of patients and entails significant morbidity and high social costs. It is most often caused by staphylococci, which are introduced perioperatively. They are a source of prolonged seeding and difficult to treat due to antibiotic resistance; therefore, infection prevention by prosthesis coating with nonantibiotic-type anti-infective substances is indicated. A renewed interest in topically used silver has fostered development of silver nanoparticles, which, however, present a potential health hazard. Here we present new silver coordination polymer networks with tailored physical and chemical properties as nanostructured coatings on metallic implant substrates. These compounds exhibited strong biofilm sugar-independent bactericidal activity on in vitro-grown biofilms and prevented murine Staphylococcus epidermidis implant infection in vivo with slow release of silver ions and limited transient leukocyte cytotoxicity. Furthermore, we describe the biochemical and molecular mechanisms of silver ion action by gene screening and by targeting cell metabolism of S. epidermidis at different levels. We demonstrate that silver ions inactivate enzymes by binding sulfhydryl (thiol) groups in amino acids and promote the release of iron with subsequent hydroxyl radical formation by an indirect mechanism likely mediated by reactive oxygen species. This is the first report investigating the global metabolic effects of silver in the context of a therapeutic application. We anticipate that the compounds presented here open a new treatment field with a high medical impact. PMID:20660682

  8. Visualization of Ion Conductivity: Vapochromic Luminescence of an Ion-Conductive Ruthenium(II) Metalloligand-Based Porous Coordination Polymer.

    PubMed

    Watanabe, Ayako; Kobayashi, Atsushi; Saitoh, Erika; Nagao, Yuki; Yoshida, Masaki; Kato, Masako

    2015-12-01

    We synthesized a new porous coordination polymer {La1.75(OH)1.25[Ru(dcbpy)3]·16H2O} (La7-[4Ru]4; H2dcbpy = 4,4'-dicarboxy-2,2'-bipyridine) composed of a luminescent ruthenium(II) metalloligand [Ru(4,4'-dcbpy)3](4-) and La(3+) cations. X-ray analysis for La7-[4Ru]4 revealed that the La(3+) cations and [4Ru] metalloligands are crystallized in a molar ratio of 7:4 with OH(-) counteranions and a void fraction of ?25.5%. Interestingly, La7-[4Ru]4 shows a reversible structural transition triggered by water ad/desorption, which affects not only the triplet metal-to-ligand charge-transfer ((3)MLCT) emission energy but also the ion conductivity in the solid state. This correlation suggests that La7-[4Ru]4 is an interesting material that enables visualization of the ion conductivity via the (3)MLCT emission energy. PMID:26599494

  9. A novel polythreading Ag(I) coordination polymer with blue photoluminescence

    SciTech Connect

    Duan, Xian-Ying; Yao, Jing; Lu, Chang-Sheng; Meng, Qing-Jin

    2013-04-15

    One new compound, [Ag(p-bix)]{sub 3}[Ag(Hbtc){sub 2}]·2H{sub 2}O (H{sub 3}btc=1,2,4-benzenetricarboxylate, p-bix=1,4-bis(imidazol-1-ylmethyl)-benzene), has been synthesized under hydrothermal conditions and characterized by elemental analysis, IR, PXRD, luminescent analysis, and single-crystal X-ray diffraction. X-ray structural analysis revealed that 0-D unit [Ag(Hbtc){sub 2}]{sup 3?} and two kinds of 1-D linear chain [Ag(p-bix)]{sub ?}{sup +}, can be found within the crystal structure. The combination of 0-D [Ag(Hbtc){sub 2}]{sup 3?} unit and 1-D undulated chain [Ag1(p{sub 1}-bix)]{sub ?}{sup +} through weak Ag–O bond gave rise to 2-D anionic supramolecular doublelayer. Then the grids of the 2-D layer are threaded by 1-D linear cationic chain [Ag2(p{sub 2}-bix)]{sub ?}{sup +} to generate entangled 3-D architecture with unusual poly(pseudo-rotaxane)-type arrangements. Luminescent properties of the title complex were also studied in this paper. - Graphical abstract: Novel 3D polythreading supramolecular architecture was constructed, in which 1D linear cationic chains [Ag(p{sub 2}-bix)]{sub ?}{sup +} threaded into the grid of weak Ag–O bonded anionic 2D sheet. Highlights: ? Novel 1D{sup +}+2D{sup ?}?3D polythreading coordination complex was reported. ? Diverse conformations of p-bix result in different 1D [Ag(p-bix)]{sub ?}{sup +} chains. ? The title complex displayed blue photoluminescence at room temperature.

  10. Systematic syntheses and metalloligand doping of flexible porous coordination polymers composed of a Co(III)-metalloligand.

    PubMed

    Kobayashi, Atsushi; Suzuki, Yui; Ohba, Tadashi; Ogawa, Tomohiro; Matsumoto, Takeshi; Noro, Shin-ichiro; Chang, Ho-Chol; Kato, Masako

    2015-03-16

    A series of flexible porous coordination polymers (PCPs) RE-Co, composed of a Co(III)-metalloligand [Co(dcbpy)3](3-) (Co; H2dcbpy = 4,4'-dicarboxy-2,2'-bipyridine) and lanthanide cations (RE(3+) = La(3+), Ce(3+), Pr(3+), Nd(3+), Sm(3+), Eu(3+), Gd(3+), Tb(3+), Er(3+)), was systematically synthesized. X-ray crystallographic analysis revealed that the six carboxylates at the top of each coordination octahedron of Co(III)-metalloligand were commonly bound to RE(3+) cations to form a rock-salt-type porous coordination framework. When RE-Co contains a smaller and heavier RE(3+) cation than Nd(3+), the RE-Co crystallized in the cubic Fm-3m space group, whereas the other three RE-Co with larger RE(3+) crystallized in the lower symmetrical orthorhombic Fddd space group, owing to the asymmetric 10-coordinated bicapped square antiprism structure of the larger RE(3+) cation. Powder X-ray diffraction and vapor-adsorption isotherm measurements revealed that all synthesized RE-Co PCPs show reversible amorphous-crystalline transitions, triggered by water-vapor-adsorption/desorption. This transition behavior strongly depends on the kind of RE(3+); the transition of orthorhombic RE-Co was hardly observed under exposure to CH3OH vapor, but the RE-Co with smaller cations such as Gd(3+) showed the transition under exposure to CH3OH vapors. Further tuning of vapor-adsorption property was examined by doping of Ru(II)-metalloligands, [Ru(dcbpy)3](4-), [Ru(dcbpy)2Cl2](4-), [Ru(dcbpy)(tpy)Cl](-), and [Ru(dcbpy)(dctpy)](3-) (abbreviated as RuA, RuB, RuC, and RuD, respectively; tpy = 2,2':6',2?-terpyridine, H2dctpy = 4,4?-dicarboxy-2,2':6',2?-terpyridine), into the Co(III)-metalloligand site of Gd-Co to form the Ru(II)-doped PCP RuX@Gd-Co (X = A, B, C, or D). Three Ru(II)-metalloligands, RuA, RuB, and RuD dopants, were found to be uniformly incorporated into the Gd-Co framework by replacing the original Co(III)-metalloligand, whereas the doping of RuC failed probably because of the less number of coordination sites. In addition, we found that the RuA doping into the Gd-Co PCP had a large effect on vapor-adsorption due to the electrostatic interaction originating from the negatively charged RuA sites in the framework and the charge-compensating Li(+) cations in the porous channel. PMID:25712451

  11. Series of coordination polymers based on 4-(5-sulfo-quinolin-8-yloxy) phthalate and bipyridinyl coligands: Structure diversity and properties

    NASA Astrophysics Data System (ADS)

    Feng, Xun; Liu, Jing; Li, Jin; Ma, Lu-Fang; Wang, Li-Ya; Ng, Seik-Weng; Qin, Guo-Zhan

    2015-10-01

    Reactions between later metal salts and conjugational N-hetrocyclic sulfonate/ carboxylic acid under the presence of bipyridyl auxiliary ligands afforded a series of manganese, nickel, zinc, silver, cadmium coordination polymers bearing with phenyl pendant arm attached to quinoline skeletons, and they have been characterized by elements analysis, thermogravimetry, infrared spectroscopy and single-crystal X-ray diffraction studying. The series of polymers show interesting structural diversity in coordination environment, dimensions and topologies. They are all built from 2-D networks constructed from metal cluster through sulfonate or carboxylate groups, as the secondary building unit (SBU). The thermalgravimetric analyses show that they display framework stabilities in solid state. Variable-temperature magnetic susceptibility studies reveal the existence of antiferromagnetic interactions between adjacent Mn (II) ions in 1, and ferromagnetic interactions between Ni(II) ions for 2, respectively. The photo-luminescence properties of 3-5 have also been investigated systemically.

  12. Extending the lanthanide-terephthalate system: Isolation of an unprecedented Tb(III)-based coordination polymer with high potential porosity and luminescence properties

    NASA Astrophysics Data System (ADS)

    Le Natur, François; Calvez, Guillaume; Freslon, Stéphane; Daiguebonne, Carole; Bernot, Kevin; Guillou, Olivier

    2015-04-01

    A novel coordination polymer with chemical formula {[Tb(bdc)1.5(H2O)]?(DMF)(H2O)}? (1) has been synthesized by reaction between 1,4-benzene-dicarboxylic acid (H2bdc) and di-cationic hexanuclear entity [Tb6O(OH)8(NO3)6(H2O)12]2+ in an ethylene glycol (EG)/N,N-dimethylformamide (DMF) mixture. This compound has been obtained as single crystals by slow evaporation in air at room temperature. If the hexanuclear entity is destroyed during the reaction, the coordination polymer that is obtained is original and presents promising potential micro-porosity and luminescent properties. It crystallizes in the monoclinic system, space group C12/c1 (No. 15) with the cell parameters a = 23.7540(1) Å, b = 10.5390(4) Å, c = 19.7580(3) Å, ? = 125.8100(1)° and Z = 8.

  13. Potassium induced stitching of a flexible tripodal ligand into a bi-metallic two-dimensional coordination polymer for photo-degradation of organic dyes.

    PubMed

    Bhardwaj, Vimal K

    2015-05-21

    A novel strategy for the stitching of a tripodal ligand into a bi-metallic two-dimensional (2D) coordination polymer has been reported. The reaction of 5-nitrosalicylaldehyde based ligand H3L with nickel acetate resulted in the metal functionalized 2D extended network via potassium induced activation of the nitro group of the ligand. The compound is highly active towards photo-degradation of organic dyes. PMID:25900142

  14. Polymers.

    ERIC Educational Resources Information Center

    Tucker, David C.

    1986-01-01

    Presents an open-ended experiment which has students exploring polymer chemistry and reverse osmosis. This activity involves construction of a polymer membrane, use of it in a simple osmosis experiment, and application of its principles in solving a science-technology-society problem. (ML)

  15. Secondary ligand-directed assembly of Co(II) coordination polymers based on a pyridine carboxylate ligand

    SciTech Connect

    Cao, Ke-Li; Zhang, Yi-Ping; Cai, Yi-Ni; Xu, Xiao-Wei; Feng, Yun-Long

    2014-07-01

    To investigate the influence of hydrogen bonds and secondary ligands on the structures and properties of the resulting frameworks, five new Co(II) compounds have been synthesized by the reactions of Co(II) salts and 3,5-bis(pyridin-4-ylmethoxy)benzoic acid (HL) with four rationally selected dicarboxylic acid ligands. Without secondary ligand, we got one compound [CoL{sub 2}(H{sub 2}O){sub 2}]{sub n}·2nH{sub 2}O (1), which possesses a 1D chain structure. In the presence of ancillary ligands, namely, 1,3-adamantanedicarboxylic acid (H{sub 2}adbc), terephthalic acid (H{sub 2}tpa), thiophene-2,5-dicarboxylic acid (H{sub 2}tdc) and 1,4-benzenedithioacetic acid (H{sub 2}bdtc), four 3D structures [Co{sub 2}L{sub 2}(adbc)]{sub n}·nH{sub 2}O (2), [Co{sub 2}L{sub 2}(tpa)]{sub n} (3), [Co{sub 2}L{sub 2}(tdc)]{sub n} (4), [Co{sub 2}L{sub 2}(bdtc)(H{sub 2}O)]{sub n} (5) were obtained, respectively. It can be observed from the architectures of 1–5 that hydrogen bonds and secondary ligands both have great effects on the spatial connective fashions, resulting in the formation of various dimensional compounds. The XRPD, TGA data of title polymers and the magnetic properties for 2 and 5 have also been investigated. - Graphical abstract: The structural differences show that the ancillary ligands have great effects on the spatial connective fashions, resulting in the formation of various dimensional compounds. - Highlights: • Five new Co(II) coordination polymers have been synthesized by solvothermal reactions based on 3,5-bis(pyridin-4-ylmethoxy)benzoic acid (HL). • The long-flexible ligand (HL) is a good candidate to produce interpenetrating architectures. • The secondary dicarboxylic acid ligands play important roles in the spatial connective fashions and the formation of various dimensional compounds. • The magnetism studies show that both 2 and 5 exhibit antiferromagnetic interactions.

  16. One-dimensional electromagnetic band gap structures formed by discharge plasmas in a waveguide

    SciTech Connect

    Arkhipenko, V. I.; Simonchik, L. V. Usachonak, M. S.; Callegari, Th.; Sokoloff, J.

    2014-09-28

    We demonstrate the ability to develop one-dimensional electromagnetic band gap structure in X-band waveguide solely by using the positive columns of glow discharges in neon at the middle pressure. Plasma inhomogeneities are distributed uniformly along a typical X-band waveguide with cross section of 23×10 mm². It is shown that electron densities larger than 10¹? cm ?³ are needed in order to create an effective one-dimensional electromagnetic band gap structure. Some applications for using the one-dimensional electromagnetic band gap structure in waveguide as a control of microwave (broadband filter and device for variation of pulse duration) are demonstrated.

  17. Cooperative many-atom response in a one-dimensional electromagnetic waveguide

    NASA Astrophysics Data System (ADS)

    Ruostekoski, Janne; Javanainen, Juha

    2015-05-01

    One-dimensional nature of several nanophotonic devices provides enhanced atom-light coupling due to tight light confinement. We investigate a cold atom cloud coupled to a one-dimensional waveguide and study collective many-atom effects in such a system when light mediates strong interactions between the atoms. The atoms respond cooperatively to incident light in a one-dimensional continuum of electromagnetic modes of the waveguide as a result of recurrent scattering processes. The atom-waveguide system displays light transport phenomena distinct from those of many-atom cavity quantum electrodynamics. We specifically address the effects of atom statistics and interactions.

  18. The one-dimensional Boltzmann gas: The ergodic hypothesis and the phase portrait of small systems

    SciTech Connect

    Rouet, J.L. ); Blasco, F.; Feix, M.R. )

    1993-04-01

    The concept of ergodicity and its application to microcanonical systems composed of few particles of different masses are clarified. The distribution functions in position and velocity are theoretically derived and numerically verified. Moreover, the authors deal with a one-dimensional Boltzmann gas where the order relation (connected to the one dimensionality) brings constraints depending on the two classes of boundary conditions enforced (reflecting, periodic). The numerical simulations on a one-dimensional Boltzmann gas act as real experiments and allow them to play on the constraints to which the system is subjected. 9 refs., 11 figs.

  19. Vapochromic Luminescence and Flexibility Control of Porous Coordination Polymers by Substitution of Luminescent Multinuclear Cu(I) Cluster Nodes.

    PubMed

    Hayashi, Takahiro; Kobayashi, Atsushi; Ohara, Hiroki; Yoshida, Masaki; Matsumoto, Takeshi; Chang, Ho-Chol; Kato, Masako

    2015-09-21

    Two luminescent porous coordination polymers (PCPs), i.e., [Cu2(?2-I)2ctpyz]n and [Cu4(?3-I)4ctpyz]n (Cu2 and Cu4, respectively; ctpyz = cis-1,3,5-cyclohexanetriyl-2,2',2?-tripyrazine), were successfully synthesized and characterized by single-crystal X-ray diffraction and luminescence spectroscopic measurements. Cu2 consists of rhombus-type dinuclear {Cu2I2} cores bridged by ctpyz ligands, while Cu4 is constructed of cubane-type tetranuclear {Cu4I4} cores bridged by ctpyz ligands. The void fraction of Cu4 is estimated to be 48.0%, which is significantly larger than that of Cu2 (19.9%). Under UV irradiation, both PCPs exhibit red luminescence at room temperature in the solid state (?em values of 660 and 614 nm for Cu2 and Cu4, respectively). Although the phosphorescence of Cu2 does not change upon removal and/or adsorption of EtOH solvent molecules in the porous channels, the solid-state emission maximum of Cu4 red-shifts by 36 nm (?em = 650 nm) upon the removal of the adsorbed benzonitrile (PhCN) molecules from the porous channels (and vice versa). This large difference in the vapochromic behavior of Cu2 and Cu4 is closely related to the framework flexibility. The framework of Cu2 is sufficiently rigid to retain the porous structure without solvated EtOH molecules, whereas the porous structure of Cu4 collapses easily after removal of the adsorbed PhCN molecules to form a nonporous amorphous phase. The original vapor-adsorbed porous structure of Cu4 is regenerated by exposure of the amorphous solid to not only PhCN vapor but also tetrahydrofuran, acetone, ethyl acetate, and N,N-dimethylformamide vapors. The Cu4 structures with the various adsorbed solvents showed almost the same emission maxima as the original PhCN-adsorbed Cu4, except for DMF-adsorbed Cu4, which showed no luminescence probably because of weak coordination of the DMF vapor molecules to the Cu(I) centers of the tetranuclear {Cu4I4} core. PMID:25984761

  20. Syntheses, structure and properties of three-dimensional pillared-layer Ag(I)-Ln(III) heterometallic coordination polymers based on mixed isonicotinate and hemimellitate ligands

    SciTech Connect

    Li, Xinfa; Cao, Rong

    2012-12-15

    Three pillared-layer 4d-4f Ag(I)-Ln(III) heterometallic coordination polymers (HCPs), formulated as [Ln{sub 2}Ag(hma){sub 2}(ina)(H{sub 2}O){sub 2}]{sub n} nH{sub 2}O [Ln=La(1), Pr(2), Nd(3); Hina=isonicotinic acid, H{sub 3}hma=hemimellitic acid], have been synthesized under hydrothermal conditions. Single-crystal and powder X-ray diffractions confirm that they are isostructural, which features a three-dimensional (3D) pillared-layer heterometallic structure built upon the strictly alternate arrangement of lanthanide-organic layers and [Ag(ina)] pillars. The layers and pillars are connected to each other by Ln-O and Ag-O coordination bonds. The photoluminescent property of the Nd derivative (3) has also been investigated. - Graphical abstract: Three pillared-layer 4d-4f Ag(I)-Ln(III) heterometallic coordination polymers have been synthesized and structurally characterized. Highlights: Black-Right-Pointing-Pointer Three 3D pillared-layer 4d-4f HCPs were synthesized by hydrothermal reactions. Black-Right-Pointing-Pointer The synergistic coordination strategy was employed. Black-Right-Pointing-Pointer It opens new perspective for the construction of structurally diversified 4d-4f HCPs.

  1. The first three-dimensional Fe(III)-Sr(II) heterometallic coordination polymer: poly[[diaquatetrakis(?3-pyridine-2,3-dicarboxylato)diiron(III)strontium(II)] dihydrate].

    PubMed

    Yang, Yongfeng; Li, Tao; Chen, Yanmei

    2015-10-01

    The title compound, poly[[diaqua-1?(2)O-tetrakis(?3-pyridine-2,3-dicarboxylato)-2:1:2'?(10)N,O(2):O(2'),O(3):O(3');2:1:2'?(8)O(3):O(3'):N,O(2)-diiron(III)strontium(II)] dihydrate], {[Fe2Sr(C7H3O4)4(H2O)2]·2H2O}n, which has triclinic (P-1) symmetry, was prepared by the reaction of pyridine-2,3-dicarboxylic acid, SrCl2·6H2O and Fe(OAc)2(OH) (OAc is acetate) in the presence of imidazole in water at 363?K. In the crystal structure, the pyridine-2,3-dicarboxylate (pydc(2-)) ligand exhibits ?3-?(1),?(1):?(1):?(1) and ?3-?(1),?(1):?(1),?(1):?(1) coordination modes, bridging two Fe(III) cations and one Sr(II) cation. The Sr(II) cation, which is located on an inversion centre, is eight-coordinated by six O atoms of four pydc(2-) ligands and two water molecules. The coordination geometry of the Sr(II) cation can be best described as distorted dodecahedral. The Fe(III) cation is six-coordinated by O and N atoms of four pydc(2-) ligands in a slightly distorted octahedral geometry. Each Fe(III) cation bridges two neighbouring Fe(III) cations to form a one-dimensional [Fe2(pydc)4]n chain. The chains are connected by Sr(II) cations to form a three-dimensional framework. The topology type of this framework is tfj. The structure displays O-H...O and C-H...O hydrogen bonding. PMID:26422220

  2. C-H⋯Cl relevant discrepancy on structure, magnetic and electronic conductivity of two mixed-valence Cu ICu II coordination polymers

    NASA Astrophysics Data System (ADS)

    Shi, Ling; Yang, Ping; Huang, Guang; Li, Qian; Wang, Ning; Wu, Jian-Zhong; Yu, Ying

    2011-07-01

    Two mixed-valence Cu ICu II coordination polymers [Cu ICu II(qdiol)ClL] n (qdiol 2-=2,3-dioxyquinoxalinate, L=2,2'-bipyridine, 1; L=1,10-phenanthroline, 2) were obtained in basic ethanolic solution of CuCl 2, 1,4-dihydro-2,3-quinoxalinedione and L under the solvothermal condition. 1 and 2 are similar in composition, but differ remarkably in structure. The coordination modes of Cu II, qdiol 2- and L are identical in both complexes. But the Cu I ions are two- and three-coordinated, and the Cl - ions are terminal and bridging, in 1 and 2, respectively, which are relevant to the significantly different C-H⋯Cl hydrogen bonding pattern of bpy and phen. The temperature variable magnetic susceptibilities show that 1 is paramagnetic and 2 is weakly antiferromagnetic. The complex impedance spectroscopic studies indicate that both 1 and 2 are semiconductors and 2 is more conducting.

  3. A series of divalent metal coordination polymers based on isomeric tetracarboxylic acids: synthesis, structures and magnetic properties.

    PubMed

    Han, Min-Le; Duan, Ya-Ping; Li, Dong-Sheng; Xu, Guo-Wang; Wu, Ya-Pan; Zhao, Jun

    2014-12-14

    Five new coordination polymers, namely, [Mn(2,2?-bipy)(H2O)2(H2L1)]n (1), {[Co(btb)(H2O)2(H2L1)]·0.5H2O}n (2), [Co(bib)(H2O)2(H2L1)]n (3), [Ni2(bpm)(H2O)3(L2)]n (4), and {[Co2(H2O)3(OH)(HL2)]·H2O}n (5), (H4L1 = 1,1?:2?,1??-terphenyl-4,4?,4??,5?-tetracarboxylic acid, H4L2 = 1,1?:2?,1??-terphenyl-3,3??,4?,5?-tetracarboxylic acid, 2,2?-bipy = 2,2?-bipyridine, btb = 1,4-bis(1,2,4-triazol-1-yl)butane, bib = 1,4-bis(imidazol-1-yl)butane, bpm = bis(4-pyridyl)amine), have been obtained under hydrothermal conditions. Complex 1 exhibits a 3D supramolecular framework based on 1D chains. Both complexes 2 and 3 are 3D supramolecular frameworks constructed from 1D zig-zag chains. Complex 4 features a 3D tetra-nodal (3,4,4,5)-connected architecture containing 1D ?-COO bridged chains with (5(2)·6(2)·7.9)(5(2)·6(4)·7(3)·8)2(5(2)·6)2(6(3)·7(2)·9) topology. Complex 5 shows a 3D penta-nodal (3,4,4,6,6)-connected net containing 1D ?-OH/?-COO bridged chains and mononuclear Co(II) nodes with a (4(2)·6(3)·8)(4(3))2(4(4)·6(2))2(4(4)·6(6)·8(5))2(4(4)·6(7)·8(4)) topology. Variable-temperature magnetic susceptibility measurements reveal that complexes 2 and 3 show antiferromagnetic interactions between the adjacent Co(II) ions, whereas 4 is a ferromagnetic system. PMID:25347690

  4. Zn(II) coordination polymers with flexible V-shaped dicarboxylate ligand: Syntheses, helical structures and properties

    NASA Astrophysics Data System (ADS)

    Li, Lin; Liu, Chong-Bo; Yang, Gao-Shan; Xiong, Zhi-Qiang; Liu, Hong; Wen, Hui-Liang

    2015-11-01

    Hydrothermal reactions of 2,2?-[hexafluoroisopropylidenebis(p-phenyleneoxy)]diacetic acid (H2L) and zinc ions in the presence of N-donor ancillary ligands afford four novel coordination polymers, namely, [Zn2(?2-OH)(?4-O)0.5(L)]·0.5H2O (1), [Zn(L)(2,2?-bipy)(H2O)] (2), [Zn3(L)3(phen)2]·H2O (3) and [Zn2(L)2(4,4?-bipy)] (4) (2,2?-bipy=2,2?-bipyridine; 4,4?-bipy=4,4?-bipyridine; phen=1,10-phenanthroline). Their structures have been determined by single-crystal X-ray diffraction analyses, elemental analyses, IR spectra, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analyses. Complex 1 shows a 3-D clover framework consisting of [Zn4(?4-O)(?2-OH)2]4+ clusters, and exhibits a novel (3,8)-connected topological net with the Schläfli symbol of {3·4·5}2{34·44·52·66·710·82}, and contains double-stranded and two kinds of meso-helices. 2 displays a helical chain structure, which is further extended via hydrogen bonds into a 3-D supramolecular structure with meso-helix chains. 3 displays a 2-D {44·62} parallelogram structure, which is further extended via hydrogen bonds into a 3-D supramolecular structure with single-stranded helical chains. 4 shows a 2-D {44·62} square structure with left- and right-handed helical chains. Moreover, the luminescent properties of 1-4 have been investigated.

  5. Real-time ratiometric fluorescent assay for alkaline phosphatase activity with stimulus responsive infinite coordination polymer nanoparticles.

    PubMed

    Deng, Jingjing; Yu, Ping; Wang, Yuexiang; Mao, Lanqun

    2015-03-01

    This study demonstrates a novel ratiometric fluorescent method for real-time alkaline phosphatase (ALP) activity assay with stimulus responsive infinite coordination polymer (ICP) nanoparticles as the probe. The ICP nanoparticles used in this study are composed of two components; one is the supramolecular ICP network formed with guanine monophosphate (GMP) as the ligand and Tb(3+) as the central metal ion, and the other is a fluorescent dye, i.e., 7-amino-4-methyl coumarin (coumarin) encapsulated into the ICP network. Upon being excited at 315 nm, the ICP network itself emits green fluorescence at 552 nm. Coumarin dye encapsulated in the ICP network emits weak fluorescence at 450 nm upon excitation at the same wavelength (315 nm), and this fluorescence emission becomes strong when the encapsulated dye is released from the network into the solution phase. Hence, we develop a ratiometric fluorescent assay based on the ALP-induced destruction of the supramolecular ICP network and the release of coumarin. This mechanism can be used for real-time ratiometric fluorescent monitoring of ALP activity by continuously measuring the ratio of fluorescent intensity at the wavelength of 552 nm (F552) to that at 450 nm (F450) (F552/F450) in the time-dependent fluorescent spectra of the coumarin@Tb-GMP suspension containing ALP with different activities. Under the experimental conditions employed here, the F552/F450 value is linear with the ALP activity within a range from 0.025 U/mL to 0.2 U/mL. The detection limit is down to 0.010 U/mL (S/N = 3). Moreover, the assay developed here is employed for ALP inhibitor evaluation. This study offers a simple yet sensitive method for real-time ALP activity assay. PMID:25634037

  6. Using a locally one-dimensional method for solving the heat conductivity equation to determine the thermal state of cooled rotor disks

    NASA Astrophysics Data System (ADS)

    Bileka, B. D.; Kabkov, V. Ia.

    A locally one-dimensional method is used for calculating the steady-state thermal condition of rotor disks by consecutively solving the axisymmetric and three-dimensional problems and coordinating the solutions over the reference radius. Unsteady state calculations are also carried out for a disk using a two-dimensional formulation for the part of the disk located below the reference radius. Results of calculations for a series of gas turbine engine disks are presented and compared with experimental data.

  7. Modeling of One-Dimensional Smoldering of Polyurethane in Microgravity Conditions 

    E-print Network

    Rein, Guillermo; Bar-Ilan, Amnon; Fernandez-Pello, Carlos; Ellzey, Janet L; Torero, Jose L; Urban, David

    Results are presented from a model of forward smoldering combustion of polyurethane foam in microgravity. The transient one-dimensional numerical-model is based on that developed at the University of Texas at Austin. The ...

  8. Wave equation on one-dimensional fractals with spectral decimation and the complex dynamics of polynomials

    E-print Network

    Ulysses Andrews; Grigory Bonik; Joe P. Chen; Richard W. Martin; Alexander Teplyaev

    2015-05-22

    We study the wave equation on one-dimensional self-similar fractal structures that can be analyzed by the spectral decimation method. We develop efficient numerical approximation techniques and also provide uniform estimates obtained by analytical methods.

  9. Plasmonic response in a one-dimensional periodic structure of metallic rods

    E-print Network

    . Because of the similar behavior of metals in this frequency range, stainless steel and copper rods distance compared to their diameter with a one- dimensional periodicity. Under transverse magnetic TM in

  10. One-dimensional nanostructure-guided chain reactions: Harmonic and anharmonic interactions

    E-print Network

    Nair, Nitish

    We have performed a parametric study of self-propagating chain reactions along a one-dimensional bead-spring array. The coupling between beads is modeled using harmonic and anharmonic Fermi-Pasta-Ulam (FPU)-? and ?[superscript ...

  11. Non-unique results of collisions of quasi-one-dimensional dissipative solitons.

    PubMed

    Descalzi, Orazio; Brand, Helmut R

    2015-12-13

    We investigate collisions of quasi-one-dimensional dissipative solitons (DSs) for a large class of initial conditions, which are not temporally asymptotic quasi-one-dimensional DSs. For the case of sufficiently small approach velocity and sufficiently large values of the dissipative cross-coupling between the counter-propagating DSs, we find non-unique results for the outcome of collisions. We demonstrate that these non-unique results are intrinsically related to a modulation instability along the crest of the quasi-one-dimensional objects. As a model, we use coupled cubic-quintic complex Ginzburg-Landau equations. Among the final results found are stationary and oscillatory compound states as well as more complex assemblies consisting of quasi-one-dimensional and localized states. We analyse to what extent the final results can be described by the solutions of one cubic-quintic complex Ginzburg-Landau equation with effective parameters. PMID:26527813

  12. Quantum phases of hard-core dipolar bosons in coupled one-dimensional optical lattices

    E-print Network

    Capogrosso-Sansone, B.

    Hard-core dipolar bosons trapped in a parallel stack of N ? 2 one-dimensional optical lattices (tubes) can develop several phases made of composites of particles from different tubes: superfluids, supercounterfluids, and ...

  13. A moving mesh WENO method for one-dimensional conservation laws

    E-print Network

    Yang, Xiaobo; Huang, Weizhang; Qiu, Jianxian

    2012-10-01

    In this paper, we develop an efficient moving mesh weighted essentially nonoscillatory (WENO) method for one-dimensional hyperbolic conservation laws. The method is based on the quasi-Lagrange approach of the moving mesh strategy in which the mesh...

  14. Simulating higher-dimensional geometries in GADRAS using approximate one-dimensional solutions.

    SciTech Connect

    Thoreson, Gregory G.; Mitchell, Dean James; Harding, Lee T.

    2013-02-01

    The Gamma Detector Response and Analysis Software (GADRAS) software package is capable of simulating the radiation transport physics for one-dimensional models. Spherical shells are naturally one-dimensional, and have been the focus of development and benchmarking. However, some objects are not spherical in shape, such as cylinders and boxes. These are not one-dimensional. Simulating the radiation transport in two or three dimensions is unattractive because of the extra computation time required. To maintain computational efficiency, higher-dimensional geometries require approximations to simulate them in one-dimension. This report summarizes the theory behind these approximations, tests the theory against other simulations, and compares the results to experimental data. Based on the results, it is recommended that GADRAS users always attempt to approximate reality using spherical shells. However, if fissile material is present, it is imperative that the shape of the one-dimensional model matches the fissile material, including the use of slab and cylinder geometry.

  15. ONE-DIMENSIONAL PSEUDO-HOMOGENEOUS PACKED BED REACTOR MODELING INCLUDING NO-CO KINETICS

    E-print Network

    Srinivasan, Anand

    2011-08-31

    consisting of small channels employing laminar flow. However, often the reaction rate expressions utilized in these models are derived from more conventional packed bed reactor experimental setups. The aim of this thesis is to develop a one-dimensional pseudo...

  16. Ultra-refractive and extended-range one-dimensional photonic crystal superprisms

    NASA Technical Reports Server (NTRS)

    Ting, D. Z. Y.

    2003-01-01

    We describe theoretical analysis and design of one-dimensional photonic crystal prisms. We found that inside the photonic crystal, for frequencies near the band edges, light propagation direction is extremely sensitive to the variations in wavelength and incident angle.

  17. One-dimensional two-phase reacting gas nonequilibrium performance program

    NASA Technical Reports Server (NTRS)

    Cherry, S. S.; Frey, H. M.; Kliegel, J. R.; Quan, V.

    1968-01-01

    Computer program calculates the inviscid one-dimensional equilibrium, frozen, and nonequilibrium nozzle expansion of propellant exhaust mixtures containing carbon, hydrogen, oxygen, nitrogen, fluorine, chlorine and either aluminum, beryllium, boron or lithium. This program performs calculations for conical nozzles only.

  18. Wave–vortex decomposition of one-dimensional ship-track data

    E-print Network

    Ferrari, Raffaele

    We present a simple two-step method by which one-dimensional spectra of horizontal velocity and buoyancy measured along a ship track can be decomposed into a wave component consisting of inertia–gravity waves and a vortex ...

  19. A one-dimensional nonlinear corner balance method for solving the neutron transport equation 

    E-print Network

    Castrianni, Christopher Lee

    1994-01-01

    The one-dimensional nonlinear comer balance method is a new spatial discretization scheme for solving the transport equation on grids consisting of arbitrarily connected polygonal meshes. It is a conceptually simple method based on particle balance...

  20. Finite time blow-up for a one-dimensional quasilinear parabolic-parabolic chemotaxis system

    E-print Network

    CieÅ?lak, Tomasz

    2008-01-01

    Finite time blow-up is shown to occur for solutions to a one-dimensional quasilinear parabolic-parabolic chemotaxis system as soon as the mean value of the initial condition exceeds some threshold value. The proof combines a novel identity of virial type with the boundedness from below of the Liapunov functional associated to the system, the latter being peculiar to the one-dimensional setting.